Jeff Perrin

Dec 162007

So I am just sitting there responding to some NASIOC posts, and I get the call…… “Your 2008 STI is here!!!” our good buddy at our dealer tells me.  This was a huge surprise to us as we had all been told they would be in by the end of January!  It’s December, and we already got our car.  Time to get to work!


When ever we get a new car, the first thing we do is go over all the new things, and changes done from the previous models, and in this case from the WRX.  For us, getting a new model of a car, is like opening Christmas presents. First off, from the WRX, this car is very different.  They may share a few of the same parts, like the chassis, and dash, but that is where similarities end.  With our STI came a very “Mini Cooper” type of media pack.  Magazines, brochures, tattoo, kill markers, listing of all Subaru clubs…….



The obvious changes are the flares.  2007 and previous model WRX’s had the very distinguished wheel well bulges.  So when the 2008 WRX came out with little to no bulge, I was a little disappointed.  One of the more distinguishing features of the WRX/STI was taken away.   Anyone else who feels the same, should go look at a 2008 STI, you will not be disappointed!


Subaru took their race-car-like bulge to the next level. There is roughly 2″ more fender flare on the STI vs. the WRX.  When looking them both side by side, this is very noticeable and makes the WRX look more “relaxed” and more of a grocery getter!


To incorporate the flairs into the rest of the body, Subaru beefed up the front bumper and left the flair open where it meets the door.  The open vent at the door really adds to the race car look, and makes is much more aggressive.


The front bumpers are wider and the lower intake is much more open looking.  I say looking because of the black colored part of the plastic.  The black part is just asking for us to cut it out for a front mounted intercooler.  This contrasting black plastic is carried around to the fog light area to an even more aggressive look to the car.  If you have seen the pics of the prototype WRC STI, you will see similar type styling.




Other than the flares the STI has a larger wing than the WRX.  It’s rather the same shape just longer and with some raised sides.  This is better looking than the WRX, but still could use some improvements. We have a few things up our sleeve that should bring this part of the car back to life!


Right below the wing is that really bad looking, or normally bad looking Chrome panel. On the STI this part is not chrome, but color matched to the body, a huge improvement over the WRX hatch.  This removal of chrome was continued to the front grill. This was one of the biggest things people complained about when the 08 WRX debuted.




The scoop for the STI model is unchanged from the WRX.  In the past Subaru has always stuck a larger scoop on the STI to go with the larger intercoolers that came on them. But the last couple models have kept the same size scoop. The scoop is actually very large, but it’s a little deceiving until you get right down and look at it.  When we show customers our WRX or STI, its one of the things people talk about.  No more snow shovel to try to look over while driving, just a nice bulge.


One thing that I didn’t pick up on right away is the badges.  STI has always been pink, but on the 08, they are red!  I didn’t notice this at first because our car is white, and from far away, red and white make pink.


Again, Subaru is making it more appealing to more people.  But they still kept the STI pink in some places.



In a quick glance, nothing has change.  Take a second look and you will find all the little things that are different.

Starting from left to right the first thing is the intake system. The intake has the newer smaller Denso MAF sensor, and Legacy type intake air box.  Both these items were the same as found on the WRX, but the difference is in the silencer.  When we first pulled apart the 2008 WRX, I noticed the air box was the same as the Legacy, but no silencer. In fact it had the place to snap one in, but the hole was blocked off.  The STI has the silencer!  Not sure why but I guess to make the engine quieter. Just like the Legacy platform, the power steering reservoir, and ABS is moved back to the shock tower.  Subaru relocated the boost control solenoid from the shock tower to the top of the intake manifold. This is a very distinguishing part of the 2008 STI. The solenoid is covered by/held on by a nicely formed steel shroud.


The intercooler looks to be similar to ones found on the older STI’s but with no STI logo painted on the face.  Actually it’s quite a bit larger than the previous STI IC.  The new STI intercooler has a bracket that now bolts to the head, instead of the block, which allows the IC to stretch further over the turbo.  This newer wider IC fits the wider opening of the hood scoop and definitely makes better use (compared to the WRX) of the air traveling through the scoop.  While the PERRIN WRX TMIC fits right now, this gives us some more freedom to make an even Bigger Intercooler! The turbo that this new TMIC covers up is not labeled like other turbos.  Is it a VF40, 39, 43, who knows, we will have to pull it off to discover the exact size. But base on our initial dyno numbers we saw, its not much different than the previous STI turbo.

Just like the 2008 WRX, the STI engine has the secondary air pump installed.  Some may be thinking that has to go!  This is a great way for Subaru to keep their engines within the emissions guidelines with out having to cut back on power. So be happy its there and that your engine makes 305HP!  The Other strange thing is the fuel system. Its looks pretty similar, but the fuel pressure regulator has moved to the shock tower.   Not only that, but the feed and return line feed into the regulator. It’s sort of a balanced fuel system.   I am sure Subaru did this to make it close to a return less system but not a return less system.  This setup will minimize fuel traveling through the rail and heating up, then traveling back to the tank. Hot fuel is bad for a couple reasons, and anyone who has been on the dyno with no gas in the tank can contest how hot fuel gets, and how it hurts power.


After that there is nothing else really visible under the hood.  But wait there is something you can’t see, and this is a very annoying part to be missing.  The AC belt has no tensioner on it!  What?  I discovered this on the WRX when I went to throw on a PERRIN crank pulley on the engine.  Then I noticed there was No AC tensioner.  There must be something we can do about this, but it will have to wait.   Other than that that is all the visible things in the engine bay.  Well there is something you can kind of see…..


The one thing about the 2008 STI that will either make this engine the best engine Subaru has ever made, or make it the 2ndmost complicated (behind the Ez30R) is the Dual AVCS.  Not only does the ECU change the timing of the intake cam depending on load, but now it can change the exhaust cam!  This could be very cool!  I am sure Subaru says they did it for emissions, and blah, blah, blah, but what will it do for tuning? We have seen what varying the cams can do for turbo spool up (decrease the lag time), but what can changing the Exhaust cam timing do?  This is something we will have to wait and see.  From our initial dyno testing, and data logging using the DeltaDash, the Exhaust cam is being retarded. Which when teamed with an advancing intake cam, this can create more valve overlap.  Normally this is good in NA high revving engines, and bad for boosted engines. But who knows what it will do for power or spool, we will just have to wait until we can tune the ECU.


If anyone has looked at the last few STI engines Subaru has made, they have seen the lower part of the head, with the blanked out fittings for a sensor to go. Well now there is finally something filling the hole!  And now both the top and bottom of the cam covers have bulges! A small but interesting difference from the WRX to the STI is the STI has an oil cooler/warmer where the WRX did away with this.  The 2008 WRX is the first turbo Subaru engine to not use an oil cooler in a very long time.  Obvious, this was a way to cut some cost out of the car on the WRX.


The HP specs on the engine are a little different than previous STI’s.  The past STI models (2004-2006) were rated at 300 engine HP and 300ft-lbs of torque.  The 2008 is rated at 305 engine HP and 290 ft-lbs of torque.  So why the change?  This has to do with the SAE ratings that changed a while back.  The 2007 STI was rated at 293HP and 290ft-lbs of torque. So Subaru has added some power, and kept the same peak torque but lower the RPM at which it hits 290ft-lbs.  But I think there is a little more to the story.  I think Subaru underrated the 2007 STI with the new SAE specs in place.  In late 2005 a new SAE HP correction was put in place and while this caused some cars manufactures engine HP ratings to drop, some increased. Subaru’s HP numbers stayed the same, but when the 2007 model year STI, (first batch of Subaru’s affected by this change) the numbers dropped, to the 293/290.  What is strange, is that many people were finding the 2007 STI was making more power than before! Not a lot but 10-20 more HP than previous cars, and with a lower HP, that seems kind of strange??  Hmmm, now for 2008 they claim more HP and same torque at a lower RPM, but with less working RPM?  Seems like they might have kept the same power, as the previous year and cut back the Redline.  Who, knows, but it is strange.


The Exhaust is again similar but different than the WRX exhaust. Similar in that it’s a tube that goes from the front of the car to back, and bolts to flange on the muffler.  They both have transverse mounted mufflers, but that is where things start to change.  The STI steps up the diameter of the exhaust, and gets rid of the funny shaped center mounted resonator for a normal round type. The muffler is similar to the WRX, but the obvious change is the tips. The STI has a new distinct look, kind of Euro, kind of BMW like dual twin tips.


The muffler is about the same size, but with the different tip configuration.  The larger piping, different resonator, and tip configuration make for a nice change in the exhaust note.



The big suspension change was done with the release of the 2008 WRX and now the STI takes it a step further.  Like the Engine if you take a quick glance under the car and it doesn’t look a whole lot different, but in fact there are a few very important differences to note. Starting from the front of car, the STI suspension is laid out just like the 08 WRX, and previous Legacy models.  No lower subframe and the vertical control arm bushings are there.  The control arms are the forge aluminum type similar to what was installed on the Legacy Spec-B. The front swaybar is just like every other Subaru out there, 20mm.


Nothing other than that to take note of, other than some funny looking engine mounts.  Subaru claimed that the 2008 WRX engine and tranny were lowered roughly .5″ over older Impreza’s. While this might be true on the WRX, it is very noticeable on the STI.  The front engine motor mounts are noticeably flatter, looking as though they had been smashed in a 100 ton press.  Also gone are the cheap, rubbery plastic engine mounts.  Moving back toward the tranny, we find the same thing.  The tranny mount was also shorter than before. Besides lowering the center of gravity the lower mounts make the engine and tranny stiffer, providing a better transmission of power from the engine to the wheels.  And like the other STI tranny mounts, its solid across the middle of it.


Just like the 2007 STI the 2008 STI has taller gear ratios for the 2nd, 3rd, and 4th gears.  In the 2007 STI this was a noticeable change and made for a better delivery of the power across the entire speed range of the car.  The clutch is the same nice and smoother engaging clutch of the past.  We will soon find out how much torque it can hold!  The shifter seems shorter than I remember, but this could be because I was used to the longer stock WRX SS I had been driving lately.  Still in my opinion, the height of the knob seems too short, but I am tall guy, so shorter shifters are not something i have ever liked. Shorter throw, now that is a different story.   Since the WRX came out, I always thought that it needed to be a couple inches taller.  One strange thing with the tranny is the dipstick is gone!  Now in its place is a Socket cap screw plugging the hole.  So where did it go?  The dip stick altogether is gone, and now has the more normal side fill plug.  For those of us who do our own service, this is not going to be as easy as it once was to change the tranny oil.

As we get to the back of the car, again the suspension is similar to the WRX, but a couple things are different.  One is the differential cradle. The cradle on the WRX is a steel formed piece, and like other STI parts, its aluminum and a bit lighter.  The other thing about the rear suspension is the swaybar is bigger. The WRX uses a 15mm and the STI has an 18mm. Overall this seems small compared to the older cars, but because of the way the swaybar, is designed, this has a greater overall stiffness than the 19mm bars of the past.


The Suspension bushing and rear subframe bushings seem a little stiffer, but it will take some part number cross referencing to figure this out.

Last but not least, the wheel and tires.  The wheels are huge for the STI.  Wheels are 18×8.5″ with a 55 offset. The older STI wheels were 17×7.5, and later changed to 17×8.  The largest tire that came on previous STI’s was a 235, and now they have monster wide 245!  Like other changes to the STI, Subaru picked a more subdued tire.  Gone is the super sticky Potneza for a Dunlop with a tread wear rating of 300.  Some magazines have done some skid pad tests and shown a slight drop in lateral G’s on the 08, which is most likely from change in tires.  While the 08 STI has a lower lateral G rating, it has shown to be faster in the slalom and faster around the track.   To us and others reading this article, I am sure we are thinking the same thing. Who cares what it comes with, how big of a tire can we go!  With stock 8.5 wheels, 265 should be no problem, but what about a 295?  With the right width and offset, I think 295s will be common.  Imagine the grip the STI will have with some 295 Yoko Advan A048′s.  That will be scary!


More refinements on found on the insides of the STI.  The first thing you will notice is the seats and carpet, are not blue anymore, but a better grey color.  Subaru is again, trying to make their cars more appealing to everyone, and getting away from the blue is one to get the older crowd interested in the car.  The seats also get better bolsters than the older STI.  I as well as many others hated the past STI seats.  They were too flat, too hard, no bolsters.  The WRX seats were better than the STI seats!


The next most noticeable item is the center console. It’s more Legacy like, with nicer buttons, trim and the cool sliding door that covers up the cup holders.  Located on the center console is the buttons for the center diff control and I-drive functions.  The Diff control of the past was simple. There was an auto mode, and a knob to put more power to the back or front, which also allowed you to lock the diff, or leave it open.  The 08 STI has all these same features, but adds a DIFF plus and DIFF Minus setting for gravel specific, and tarmac specific settings.  And instead of the Radio Shack type roller switch, it’s a silver, luxury car type of switch.  Taking the similar styling note from the older STI, the new one has a more drastic approach to the shifter trim ring.  Previous STI’s simply took the WRX console and bolted on a ring.  Now its whole different plastic console piece compared to the WRX.  Also right above it a perfect Cell phone holder.  The WRX has a similar spot, but no rubber mat. So your phone or garage door opener just slides around, and annoys the hell out of you!


Onto the dash.  I had been driving the 08 WRX for a long time, and come to love the layout of the dash, the quality of the gauges and seating postion. Again, the STI goes a step further with the gauges, and HVAC controls.  The lighting of the dash I a little different, as is the HVAC controls.  The small bits of silver add to a nicer, more quality look to the interior.  To the left of the dash are the mirror controls, headlight leveling system, and the DSC button.  This is all similar to the WRX, except that the DSC has 2 modes.  Normally it controls both traction, and yaw or rotation of the car.  Traction control is handled by closing the throttle, and the yaw is controlled by applying the brakes.   Hit it once and both are turned off, and the DSC light turns orange. But hold it down the DSC light turns green.  This second mode does away with the traction control and keeps the yaw control in place. This mode is what most likely will be preferred for track or auto crossing.  So now if the tires slip, the ABS unit will start to apply force to the brakes, and not cut power to the engine.


The rest of the interior is about the same, but with the new grey Alcantara patched in here and there.  The seating room is the same, the trunk room is the same, speaking of the trunk, gone is the Intercooler sprayer tank.  Subaru didn’t include this in the 08 STI, which is a bummer, but it just gives us another reason to create our own tank for our water injection system.  There is a little more plastic on the doors than I would like but its Subaru not a Porsche!


Many people are complaining about how expensive the STI is this year.  The price for the base STI did go up $1000, but there is more than a $1000 in parts.  18 wheels, 245 wide tires, 2 stage DSC, New Center diff settings, Lower engine and drive train, more powerful engine, nicer interior, better seating position, telescoping steering wheel, wider track, shorter body, cool hatchback shape, and the flares all make it worth way more than $1000. Not to mention than this STI has the most potential for power and handling compared to previous STI’s.

Subaru did leave some things to be desired, but of course, no car is perfect. That is why the term “aftermarket parts” exist!

What are our plans for the STI?

We have 2 big tricks up our sleeve, things that no one else has ever done before! Besides that, there are the normal things to expect.  Turbo back exhausts, intakes, intercoolers, shifters, bushings, swaybars, endlinks, PSRS, and the most important item we plan on offering is Custom AccessPORT maps for all stages of tune.  As you are reading this, we are the first to have, and are already tuning our STI.  We are the first, and we are the ones leading the pack.  There are many exciting things in the next few months you will see from us!



















 Posted by on December 16, 2007 First Look Tagged with: , , ,
Nov 172007

Now that Project $15k has a healthy dose of power it’s time to put some focus on the suspension and brakes.


Starting with a car that has 110k miles on it probably means it has the original struts holding things together but not playing a big part in the suspension game any more.  We found this to be the case as they where worn out, rusty and leaking.  The springs have been changed in the past with some cool looking orange units.  Since we liked the ride height we will continue using these springs in the build to save some cost in that department.

So all that had to be done was swap in the new struts and clean things up a bit.  We started in the rear and found that one of the last owners put in 2006 model WRX lowering springs, we know this because they also put in 2006 model strut tops.  This is not a necessary thing but it does give us fresh rubber in the strut top bushing, a good thing.  The installation of the struts was very easy and straight forward.  One benefit we got from replacing the struts and doing some cleaning was that the car lost about 5lbs of dirt!  Not kidding, once I was done I swept the dirt into a big pile to take a picture but before I could my shop guys swept it up (dam clean freaks!)

The struts we chose are Tokico Spec D.  We chose these as a comprimise of price and performance.  This was a $10k car and I dont see the need to put 10%-15% of the vehicles value into struts, but they where still the second most expensive modification. ($530.00)

“TOKICO€™s D-Spec Series adjustable shock is a multi-use product that€™s the result of sophisticated piston and valving design. In addition, it utilizes a unique variable-aperture bypass, which is controlled by an adjustable slide valve.

D-Spec (damping specific) adjustments change both rebound and compression damping simultaneously. Between maximum soft and hard settings, the D-Spec is infinitely adjustable. For more information and to view the damping graph full size, click here.

D-Spec shocks and struts are sold in sets of four. Each set includes a manual explaining the adjustment process as well as covering suspension tuning tips.”


I could have gotten away with  just a thorough bleed job and a good brake pad but the original brake lines where probably getting a little worn by the elements and getting soft or brittle and the rotors where showing some wear grooves and the center hats where rusty.

I went ahead and installed new StopTech replacement slotted rotors that look cool with the black painted center hats, StopTech SS lines and Axxis Ultimate Brake Pads.  For brake fluid I just chose Prestone DOT4/DOT3 as again this is a budget build that will mostly see street driving so an expensive racing fluid is not needed.



 Posted by on November 17, 2007 Project Builds Tagged with: ,
Nov 172007

One of our long time local dealers Pro-Image Performance, had seen our SEMA 2006 STI limited and wanted to build their 2006 STI to be just like it.  Josh and his father both are big time track guys, and both have 2006 STI€™s.  As Josh does one thing, his father follows along and does the same thing.  They both got bored with bolt on performance, and decided to get the PERRIN Complete GT3076R Turbo Kit.  This kit includes everything to turn a stock STI  (with a catback exhaust) into a 400WHP monster.  And we mean everything, from the turbo kit, intake, fuel system, headers, and even the AccessPORT programmed and ready to run!


Ya, not sure, but this guy from Subiesport seems to show up for no reason sometimes????


Love the all black with the STI lip.  Very mean, and very stealth!  Stealth except for the huge intercooler and exhaust… and big wing…..and Brembo’s…. Nevermind…..

Josh and his father installed the kit prior to the dyno day, and with a quick base map from Surgeline tuning, they drove down to our shop and the custom tuning begun.  Unlike a lot of customer€™s tunes, peak power was not as important as durable power.  Since Josh is tracking this car, 400WHP wasn€™t that important as is keeping the engine in a safe state of tune.


dyno_turbo_proimage_perrintuning006 ’

Locked and loaded, the STI was ready to do some runs!

Like any custom tune, we started at low WG boost.  This was done at 14psi.  As expected the car make almost 300WHP and 300ft-lbs of torque when tuned!  From there we started turning up the boost!  With a very good base map built for this kit, the tuning went very smooth.




We feel this map is very safe because we stay under the OEM MAP sensors limits. This is important as this allows us to keep a boost limit in place.  For those who do not know, the stock MAP sensor can only read to about 21psi, so anytime your boost goes over this, the ECU doesn€™t know.  This means that instead of small boost spikes, you get uncontrolled 40psi boost spikes, this is bad!  Keeping the boost below this cap, allows us to build a safe map using our EBCS solenoid, and allows us to keep the OEM boost fail-safes in tact.


We never recommend that people run over 360-370WHP with the stock STI block, but here is a sort of €œglory€ run.  The extra HP was from holding 3psi extra boost until 5500RPM.   It comes down to the WHP you want is determined by the boost you run at a given RPM.  Besides running a reasonable boost level, the AFR€™s are nice and safe also.


Starting with the first run, to the last couple tuned runs, we gained 120ft-lbs of torque, and 80whp!  If the customer doesn€™t notice that, they must have a numb ass.  So what is different about this tune versus others?  Torque!  Because this is our complete turbo kit, it includes our equal length headers.  The header make the turbo spool up quicker, and in turn more torque!  The rather large torque number comes from more boost at lower RPM.  Our 2007 Limited STI made 387ft-lbs and 405WHP.  This car ran 20PSI and held it to redline. For Josh at ProImage€™s STI we ran 22psi tapering to 19psi hence a little more torque, and a little less HP up top.

The final results are very impressive with this whole thing being done on 92 octane fuel only.  Next mod for Josh (which means his dad also) is water injection.  450Ft-lbs??  If nothing else we can make the same power, but with less boost.  Again, a great thing for the track!

Thanks to Josh and his dad Stan for taking the pics along the way.  Anyone looking to get these same results give us a call, and lets get you setup!  PERRIN Performance is not quite ready for walk-in dyno tunes yet, but mid next year we will be.  With that said look for our showroom to completed early next year, and PERRIN Performances first ever Grand Opening!



 Posted by on November 17, 2007 Dyno Test & Tune Tagged with: , , , , ,
Nov 112007

All Testing was done at the 1.2, 1.5, 1.7 and 1.9 bar of boost. Below are tall the 1.7 bar runs which are the most consistent ones i had to compare with all turbos.

Not the best comparison because this is the one where the TGV housing was closed on my car. So it was killing the HP up top. Since the smaller turbo spooled slower, its possible that it effect spool a little as well.



Below was my previous favorite EFR turbo. There are two things here. The AR of the 7064 was .83 versus the 7163′s .64.  So the EFR7064 is slower spooling for sure.  The second thing is the boost falls off on the 7064. This is because the WG actuator was not strong enough. I never got a chance to install the push/pull WG actuator as i had to send the 7064 back to you.

Here is the boost curve showing the drop in boost.





The below graph is the EFR7670 and 7163.  Is the extra 22WHP work the lag??






The below graph is the GT3076r with smaller more comparable .63ar housing.


For sure the EFR7163 is the winner here. Same or better power, and better response.




And the GTX3076R test with a .82AR housing. Much laggier and only a bit more power. Again, is 20WHP worth it?




Now the fun graphs. The EFR blows the doors off the OEM IHI turbo. And hardly any less responsive.


The response shows up more here, but still its not very noticeable at all. I drove one of our employees cars and our cars are very similar feeling but mine blows the doors off his car.




This is a 2011 WRX(smaller turbo than STI) and you can see in the red run where i had the manifold really hot that it spooled quicker than this car.

 Posted by on November 11, 2007 Dyno Test & Tune
Oct 252007

It is still not the most widely known thing that PERRIN is selling the AccessPORT , but we are and we are here to show you what we are offering!

Over the next couple of weeks you will see gains had by the custom map program, but first we are going to showcase our Project 15K WRX .  We will show what the car makes in stock tuned ECU form, Base tunes supplied with the AccessPORT and the PERRIN/Surgeline tuned maps.  These tests are all done on our Project 15K WRX, which is a 2002 Blaze yellow WRX, that has a stage 1.5 package. This includes a PERRIN 3€ Catback exhaust, PERRIN Inlet hose and an intercooler hose kit.  Both items were replaced because OEM parts had failed.  This test was done with OEM downpipes to show a 100% street legal setup.

Our initial dyno runs we done with the AccessPORT flashed with the OEM map.  In this form the car runs the normal 14psi dropping to about 12psi at redline.   The dyno results are a bit higher than we had seen before on Stage 1 WRX€™s but this could be do to the intercooler hose kit and inlet hose.  This car doesn€™t have any other mods, except for 110,000miles!   We ended up with 200WHP and 190ft-lbs of torque.  While a little high, its still inline with what others see on a Dynapack.


Next up is the base AccessPORT map for a Stage 1 WRX.  They claim 25HP and 30ft-lbs of torque.  Almost exactly what they say,   The boost on these runs, was a bit higher 14psi, but held 14psi almost to redline.  So how do they get more power??  More boost, leaner fueling, and more timing.  But what is really interesting to note is how lean it ran.   This map was made to suite our fuel, and we felt this was pretty lean.  But nonetheless, no knock, or anything bad in the 7 runs we did.  We ended up with  220WHP and 220ft-lbs.

Now for the fun stuff.  Time to build a new map.  With a little bit of time spent messing with AFR€™s and optimizing timing, this is what we got!


While the PERRIN custom map blows the base Map out of the water, the biggest thing to note is the safety factor.  2 things, one the car runs richer, which in our opinion is safer overall for guys taking their car to the track, or drag racing.  Lean AFRs can make for high EGT€™s, and cause other things.  This tune could have actually been taken further by adding more timing.  While we backed some out for this run, we did it to keep the car safe.  So our map is a little richer, and a little less aggressive in timing, all and all safer!


This map was created to not only show off how our Custom Tuned AccessPORT maps make more power than base tunes, but also to build a map that anyone can buy from us.  This map is one of the many maps we offer for all stages of your modded 2.0L WRX.  For more info call PERRIN Performance at 503-693-1702

For more info about the car we used, CLICK HERE . The quick story is we are building a car with a $15K budget (including the purchase of the car) and showing people along the way, what needs to be done, what should be done, and what can be done with the remaining budget.  Since this is such a popular car, and there are lots of them out there, we wanted to show what anyone could reasonably do.  This project is known as “Project 15K” .


 Posted by on October 25, 2007 Dyno Test & Tune Tagged with: , , , , ,
Oct 232007

Selection Process and Cleaning

Not too long ago we where talking about the older WRX’s and how inexpensive they are getting in the used car market. So after some discussions we thought it would be fun to find a good example and build it on a budget (about $15k including the car). What we expect in this project is a car that will be reliable and pass all emission testing. On top of that it has to be FUN not so much a 12 second car but something you can enjoy driving to work and still be able to go play on a sunny day. But we are definitely happy if we can turn 12′s.

Step one is finding the “right” WRX. We looked at a dozen or so examples that included wagons and sedans from $9k – $13k.

Here€™s a couple examples of potential WRX that were close to what we were looking for but because of over all condition or based on the cost to repair ruled them out.

Some of these cars had interior damage that obviously came from a large dog chewing on every chewable part wile others had been seemingly dimpled like a golf ball on the exterior with not one straight panel. Finally we came across the right one for our project. It is the rarest color for 2002 (Blaze Yellow) and with no major damage it was the one. It even had a few extra goodies that could be used or sold to add to the build. After paying the small fee of $10,000 we were able to start the drive home.

Honestly the car was in good condition but it badly in need of a bath and there was a strong odder of funk coming from somewhere. All in all out of the 12 or so that we looked at it was the best choice for us and our budget of $15K

Lesson learned so far if you€™r willing to search and put in some sweat equity you can find a very nice and inexpensive WRX on the used market.

The Clean up – The first step was to clean this thing up and get rid of the smell.

Time to address the paint, even with a relatively €œokay€ body the paint was in pretty oxidized and contaminated condition. The paint felt like sand paper, if we dragged a towel over it the crap on the paint would actually snag the towel. After a thorough wash we clay bar the entire car, mirrors windows and everything. Clay is amazing, at first we where skeptical that we could revive the paint. After claying the paint really started to show potential. The next step was an abrasive polish, this removed the remaining contaminants and removed the oxidation wile getting us excited at the same time. After the aggressive polish came a fine swirl removing polish, this smoothed the finish to better than new feel. To protect the paint we finished with a layer of wax that will protect the revived finish through the coming fall months.

The second step was to be able to drive down the road and not pass out because of the smell. After completely removing the entire interior for a good cleaning we found that there was a leak on the passengers side. The pervious owner/owners installed an aftermarket down pipe and in the process cut the AC condenser €œdrip hose€ to short and it caused a leak to form in the passengers compartment. This was the cause of the smell and also the cause of our new mildew situation. After repairing the drip hose and a little extra scrubbing it was time to put everything back together. All in all we spent about a weekend scrubbing and buffing the car but let me tell you it was well worth it.

What we got on day one:

Let the cleaning begin:

While cleaning things out we found $1.22 in change to put back into the the build budget.

Additionally the car needed some paint less dent removal to get rid or minimize the door and parking lot sores, the WRX really looks amazing! It€™s now a car that anyone would be proud to drive.

DIY Perrin Rear Differential Cover Installation

While changing all of the fluids on PERRIN Project 15K we decided that we would take advantage of the situation and not only change the differential fluid but also add a little style and functionality to the rear end. Our rear diff cover is made from high strength, heat-treated cast aluminum. We’ve incorporated cooling fins into the design helping to reduce oil temps, in addition to looking good and cooling the oil better we’ve also increased the oil capacity more than 30% over stock. For a little more info click here.

Needed tools and gear:
1) New differential gasket (Can be purchased from any local Subaru dealer)
2) 1/2″ drive wrench
3) 17mm wrench or socket
4) 14mm socket
5) Jack and jack stands

This is a very straight forward installation that can be done on either a commercial vehicle hoist or floor jack.

Step 1) Raise vehicle to desired height allowing you enough room to move freely. For this you will want to use jack stands to support the vehicle while removing and installing the differential cover. NEVER WORK ON A VEHICLE SUPPORTED ONLY BY A JACK.

Step 2) Once the vehicle is raised to the desired height you will want to use the 1/2″: drive wrench to remove the lower “drain plug”. You will also want to remove the upper “fill plug” at this time as well. Place these two plugs aside to be reinstalled later.

Step 3) Time to remove tension from the differential, this will allow you to remove the studs connecting the differential to the cross support. You’ll need to get a floor jack for this next step. Placing the jack under the differential you’ll want to raise the differential roughly .5″.

Step 4) Using a 17mm socket remove the 17mm nuts securing the differential to the cross support. Remove the studs from the differential and the cross support by using the “Jam-Nut” method. (this is where you “jam” 2 17mm nuts together on one stud. Then you can remove the stud by unscrewing the nut closest to the differential). Repeat this process on the remaining stud. If this method doesn’t work you’ll have to use a stud-extracting tool.

Step 5) Once the two studs are removed from the differential and the cross support, its time to lower the differential. If needed you may want to remove or lower the exhaust system allowing yourself more working room. Because our vehicle had a differential skip plate we had to remove the exhaust. You now should see and have access to all 8 14mm bolts securing the differential cover to the differential. Using a 14mm socket remove the bolts. (NOTE: WHILE REMOVING THE DIFF COVER THERE WILL BE ADDITIONAL OIL THAT WILL BEGIN TO COME FROM THE BOTTOM OF THE DIFFERENTIAL). Once the cover is removed you’ll want to wipe out as much excess oil from the differential as possible.

Step 6) Once everything is clean you can place THE NEW DIFFERENTIAL GASKET to the PERRIN differential cover. Using the 8 14mm bolts remove earlier loosely place the cover back into place. Starting at the top two bolts tighten the bolts to 21.7ft-lbs.

Step 7) Raise the differential back into place using the floor jack. Once the differential is in place (you’ll be able to tell because the differential nut holes will line up with the cross support holes). With everything lined up you’ll want to place and tighten the two bolts/nuts removed earlier to 52ft-lbs. Before doing this thread studs into differential cover until they are bottomed out.

Step 8) Reinstall the lower drain plug into the newly installed PERRIN differential cover. Tighten this drain plug using the ½” drive wrench to 36.2ft-lbs.

Step 9) Fill differential with proper high quality gear oil until oil starts to drip from the upper fill hole. Install the upper plug and tighten to 36.3ft-lbs.

Step 10) Lower vehicle and take it for a test drive. Check for oil leaks after the test drive.


Perrin Rear Differential Subframe Lockdown System DIY

As some of you may or may not know, we here at PERRIN have taken on a little project called Project $15K. This is where we take a 2002 WRX and build the ultimate daily driver. After washing it and cleaning everything up it was time to change out all of the fluids. While doing this we decided that we should install our SLS.

Adding the PERRIN Subframe Lockdown System adds rigidity and stability to the rear end diff. This kit eliminates all driveline slop and the annoying thud that can be heard shifting from first to second. The results can be felt the first time you take off from a stop light at almost any speed. I have to say that this has to be one of the best “bang for your buck” mods I have ever done. For more information click here.

Needed tools:
1) 12mm socket or wrench
2) 17mm socket or wrench
3) Jack and Jack stand

Step 1) Raise the vehicle to a desired height allowing you enough room to move freely. For this you will want to use jack stands to support the vehicle while working on the cross support. NEVER WORK ON A VEHICLE SUPPORTED ONLY BY A JACK.

Step 2) Time to remove tension from the differential, this will allow you to lower the differential stabilizer. You’ll need to get a floor jack for this next step. Placing the jack under the differential you’ll want to raise the differential roughly .5″.

Step 3) Using a 17mm socket remove the 17mm nuts securing the differential to the cross support. Remove the studs from the differential and the cross support by using the “Jam-Nut” method. (this is where you “jam” two 17mm nuts together on one stud. Then you can remove the stud by unscrewing the nut closest to the differential). Repeat this process on the remaining stud. If this method doesn’t work you’ll have to use a stud-extracting tool.

Step 4) Once the two studs are removed from the differential and the cross support you will remove the two 17mm bolts and nuts securing the differential stabilizer to the rear sub frame. Its now time to lower the differential, you will only need to lower it slightly to allow for clearance. If needed you may want to remove or lower the exhaust system allowing your self even more working room.

Step 5) Remove or lower the differential stabilizer from the sub frame. After you have done this you can install the 4 smaller red urethane bushings around the OEM Bushings center mounting points. (2 bushings installed on each side)

Step 6) After all 4 of the PERRIN bushings are in place you can now reinstall the differential support brace into the chassis. (Don’t fully tighten just yet)

Step 7) Raise the differential back into the car, line up the stud holes with the differential support holes and reinstall the studs.

Step 8) Tighten the differential stabilizer support bolts to 70ft-lbs. Now go back and tighten the nuts on bolts on the sub frame to 70ft-lbs.

Step 9) Time to install the rear sub frame lock out bolts. You’ll want to locate the empty threaded holes on the rear sub frame. Screw the bolt and bushing into the empty hole on each side of the car. Tighten the bolts down to 60ft-lbs. (BOLTS AND SPACERS MAY MAK SOME POPPING SOUNDS WHILE THE BOLTS ARE BEING TIGHTENED INTO THE CHASSIS, THIS IS NORMAL)

Step 10) Locate the differential front support beam and the 2 outer bolts securing it to the chassis. Remove the passenger side large bolt securing the front support beam to the chassis, and the two bolts securing the plate to the chassis.

Step 11) Pull down the front support brace until there is enough room to place the new bushings on top of the OEM bushings.

Step 12) Reinstall the plate back onto the chassis and tighten the 12mm bolts to 25ft-lbs. Install the large 17mm bolt through the bushings and tighten to 100ft-lbs.

Step 13) Repeat step 10, 11, and 12 on the drivers side.

Step 14) Lower vehicle and test drive.

PERRIN Lightened Crank Pulley DIY



Perrin Performance Stealth Exhaust Diy


 Posted by on October 23, 2007 Project Builds Tagged with: , , , ,
Oct 202007


Besides building a fast and cool looking 2008 WRX, we had a goal to showcase a turbo that I think should be the most popular for the normal guy thinking of a turbo kit for his 2.5L Turbo motor. The GT3071R!  This turbo gets overlooked quite often.  It easily makes 350WHP on an STI, and on race fuel/Water injection 400WHP can also be had easily.  The GT3076R (the more popular turbo) is also good for these numbers, but can easily support an extra 50WHP beyond those numbers. So why not just go with the bigger turbo, it makes more power???  Response!  The GT3076R turbo (given similar dyno loads and same turbine AR€™s) spool about 700RPM later than the GT3071R. For an Autocross guy that wants a nice responsive turbo, and doesn€™t care about making over 400WHP the GT3071R turbo is for them.

To add to all that, this test was done with a catalytic converter. While the stock car has two of them, and to keep it 100% legal it needs two, one cat is good enough to pass the tail pipe test and to keep the ECU happy.  But still not legal, just need to make that clear.  Also with the fuel pump issue we had, we would be putting the OEM fuel pump to the test.

The results below are for a GT3071R with a .82AR housing. The smaller .63AR housing will be tested at a later date to show the difference in HP and responsiveness.

We had just made a trip to LasVegas to attend the Street Tuner Shootout event at Spring Mountain. This was the debut of the car, and we had basically no time to tune the car, except driving it around the track.  Sounds scary but with the Hydra ECU on Autotune, the AFRs were stable and safe. With 4 good sessions of tuning at 16psi, the car was running great.  But how much power were we running?  After the car was setup on the dyno, the first runs were showing at 16.7PSI, we were hitting 320WHP and  340ft-lbs.  People were asking us at the track how much we thought we were making, and guess of 320 was right on!


Before we get too far, its important to mention that Hydra came through with a custom ECU for us for this event.  Hydra put together 2 special harnesses, one that uses the stock ECU to drive the dash and one that did completely away with the stock ECU.  The later didn€™t work as the ECU has an immobilizer built into it, and it wouldn€™t let the car start.   So the pass through version was used, and installed in the car.  The Hydra on this setup fits in the glove box which is a nice clean and tidy place for it.


Tuning Time

While I have tune a bunch of cars with the Hydra, I had Tim Bailey of Surgeline tuning to come by and help out.  Tim has been tuning cars across the country by himself for about 6 months, and turned it into a full time job. He is also supplying us with our custom tuned maps for our AccessPORT program.  Yes if you haven€™t seen that PERRIN is selling a COBB part, we are!  The AP is the best ECU flash tool, so why not sell it!  Anyway as seen above, the Dyno we bought is a Dynapack, which is a great tool for our R&D stuff.  Its great for repeatability and for providing HP numbers that don’t read too high or too low.

Base Run

The difference between these two runs was a couple three degrees of timing from 5500RPM on up.   40WHP with a few degrees is somewhat expect with the detuned nature it was in.  With further fueling/timing changes and adding boost along the way we easily got to our 350WHP goal. Ya, like we were going to stop there!

The fueling seemed to make the biggest difference in power, not timing.  Timing wasn€™t really messed with a whole lot until we turned the boost up to 20psi.


21PSI, and getting close to 400WHP!

Like I somewhat expected with this smaller turbo, we would get to a point where timing would really having be retarded and fueling would get richer. The sweet spot was right at the 19psi range, where we saw the most consistent and least noisey (knock) runs.  We turned up the boost to get some good numbers, and while these were reliable runs, the boost was turned back down to 19psi, and left alone.


The final results are pretty good in my opinion. We did start to run out of fuel with the pump. Anything above 20psi and about 6500 RPM were having to add a lot more fuel.  The Hydra€™s Fuel map had a €œFuel Nipple€ as Tim called it at these upper RPMS and boost ranges.  Now that we have more time, a Walbro will surely be dropped in there and retuned on the dyno.  Most likely this will wait for the water injection install and tune.



The boost curve of the GT3071R with .82AR is very good and responsive. The above graph shows the boost curve using the WG spring (16psi) and a PERRIN MBC for the increased boost.  18psi showed a near perfectly flat boost curve (I guess curve isn€™t the right term, boost flat??) As we increase the boost, the €œcurve€ became more of a slope showing the turbo€™s efficiency starting to drop and looking at a compressor map it makes sense.  Garrett says the turbo is good to 475 Crank HP which we were getting close to at the 380WHP mark.

Sure enough, from about 6200RPM on up and 21psi, power started to drop and it was harder to keep the engine quieter.  Interesting, torque peak occurred right where is should according to the graph, right in most efficient part of the map.


Here is the GT3076R .82 graph over laid from our shop Limited STI, and the GT3071R w/.82.  As you would expect from a slightly smaller turbo, more responsive, quicker spool, torque peak is earlier, but top end power not there.  As cool as it is, to have a big huge turbo on your car, I thinks it cooler to have a more drivable car!  This car feels great on the street.  Just the right amount of power, and the 5spd (with longer gearing) really likes this turbo.

Here is the list of parts installed on the car.


FMIC, Rotated turbo kit (GT3071R) with Cat Installed, 3€ Catback Exhaust, modded injectors, Fuel rails.

Other Contributing Brands

Tial 44mmWG, Hydra Custom 2008 ECU, H&R Custom coil overs, Konig Feather Wheels, Advan Neova tires

Look for the Water injection test soon!















 Posted by on October 20, 2007 Dyno Test & Tune, Project Builds Tagged with: , , , ,
Oct 172007

It€™s a love hate relationship with any new model of car that comes out.  You either love it, or hate it, but eventually it grows on you.  I personally love the hatchback look from the side, and front, but the back is a little scary.  But a few simple things can fix that.  Getting rid of the chrome parts for painted or black out parts is a huge part of the formula.  Then lower it a bit with some nice wheels, and the car really starts to pop.

We have had our car for a couple months now, and we figure we would show you some of the progress we are making, and show our path to getting ready for its public debut at the 2008 Street tuner challenge.  So what would we be building for the 2008 WRX show car?? Well, everything!  The formula to build the show car is simple, turbo, FMIC, turbo back exhaust, fuel system that would support 500WHP, bigger swaybars, coilovers, and nice sticky wide tires, and good engine management.  While this list is easy to create in words, to create physical parts and do in about 2 weeks is the hard part.

Our car started life out as a 2008 WRX with the premium pack, and a whopping 14miles on the tripmeter.  Because they were hard to come by at the time, Subiesport Magazine used our hatchback and sedan for the latest Subiesport issue. Pics can be found HERE!

While we just moved into a nice big new building, our “Shop” was still at the old shop.  While this was a pain in the butt to drive back and forth, it was nice to have no distractions, and peace and quiet. While the shop was a little sparse, it had all the essentials to create everything we needed.



First off the exhaust. Not much to do here other than make a 3€ system thats quite!  Like our other exhaust systems, 3€ mandrel bent 304SS tubing was used, along with a straight through 3€ muffler.  Even though this was a prototype, it would be seen by many people so I end up polishing the tubing to represent what the final product would look like.


OEM midpipe bolted to PERRIN 2008 WRX Muffler.  This makes the car sound very mellow, but that cool Subaru Boxer sound finally starts to come out.


In some of the pics you will notice the system is bolted to an OEM exhaust.  This is a new feature we are trying to incorporate into a lot of our new exhausts.  This allows then end user to buy just the muffler, for some more sound, or buy just the center section to get some power, but keep things super quiet.



Another feature everyone will see in every exhaust system coming out is a V-band connection. This is a great way to make the system easier to package and provide an adjustable and gasketless connection.

The exhaust for the 2008 WRX is very different than any other Subaru in that the muffler transversely mounted.  While this adds some more complexity to the system, it adds a new look to the back of the car.  Now you can see the side of the muffler and the huge 3€ tubing.  Subaru obviously did this to cut down space needed behind the rear wheels to help shorten the car.




This shot represents what you might see driving down the road from behind.


From the back of the car, the muffler and the 3″ tubing really shows up.  Can’t wait to see what we can do with the STI!


On a side note, all the emissions related items (like the charcoal canister, and evap control solenoids) are moved to the inside of the car under the trunk’s floor.  Again Subaru moved this more toward the middle of the car to get more weight centrally located in the chassis.  One more note, the gas tank is under the back seat, not behind it!  Again more weight moved to the middle.  All of this starts to makes sense as the car (in stock form) seems to rotated better and handle better than previous models.


A set of PERRIN headers were used which are proven to gain HP across the RPM and increase spool RPM. The only difference is I coated the with VHT 2000 degree ceramic paint.  I have been using this product on the last few projects with great success.  Its simple, just clean the part really well, and spray it like paint.  And for $8 a can  you can€™t go wrong.  While I was coating the header, I figured I would coat the exhaust housing, and uppipe to the turbo kit.




Ya, who cares, no one will see it, but for a couple minutes of work, it made for a nice picture!


While Subaru has done some things to make the car handle better out of the box, Subaru has left some room for improvement.  Beauty with this car is there is lots of room to put some nice wide tires on it.  We could have gone with 255 easily with the correct offset and a little more time.  This is something we will be working on very soon. But 245 wide tires on this car is perfect for zero issues with rubbing.  Its kind of like 225s on the GD body. I just can€™t wait until the 2008 STI comes out!  Dare I say 265 or 275 with no issues???   So what kind of 245€™s would we use? We went with, what I feel to be the best street performance tire around, Advan Neova€™s.  They are not quite R compound, but very sticky, and good enough to drive on all year round, and good enough for some light track days.  Plus Yokohama hooked us up with set for this event.  The only problem was when the tires arrived.  To keep the tires connected to the car, we used some Konig Feather wheels. These are just over 17lbs for a 17″, and are very reasonably priced.

Starting at the front of the car, the front sway bar and end links fit perfect from the WRX/Legacy GT.  We chose to go with a 22mm front bar to help balance the rear sway bar we were building.  After driving the car, we might even be putting the 25mm on the front.  From there our Legacy GT PSRS plopped right into the control arms.  Yes, the 2008 WRX has those stupid super soft rubber rear control arm mounts.  This was a huge improvement to the handling as expected, and I think will be one of the most important suspension items for the new 2008 WRX/STI/LGT.  Those of you that have this part on their LGT will understand why I say that.

Onto the rear!  Of course we are going to build a rear sway bar, but what size???  Well the OEM bar is a whopping 15mm huge, so of course we are making one. But why did Subaru make it so small?  Many people will ask this question and thing that Subaru wants to make the car understeer more to suite more of the general public.  But after some measurements, Subaru was going the right way, more oversteer!  The OEM 19mm GD body rear sway bar, has an effective rate of 85lbs-in, compare this to our 22mm rear sway bar which has a rating of around 240lbs-in on the soft setting.  The new 2008 OEM 15mm bar is rated at around 130lbs-in, so its stiffer!  How can this be, simple the bar is shorter, and the leverage arms are shorter.  Going with a 17mm bar would make the effective rate about 215lbs-in, which might seem like enough.  But the STI is about to come out and I am sure it will have a larger(or stiffer) bar than the WRX, because it has in the past.  For us, this wouldn€™t be enough, so we went with a 19mm and made it with 3 holes. One hole stiffer, and one hole softer.  This made 3 rates, which vary from 260lbs-in, 340lbs-in and 440lbs-in.  This allows for settings that can be a mellow change from stock to a change that is more than 3 times stiffer than stock.  And the different settings are very noticeable.  The softer setting is a nice feature, as this will allow customers to work up toward the super stiff setting.

A prototype 2008 WRX rear swaybar was created, using the OEM bends, and some special laser cut ends.  This was sent off to be red powder coated and was had a couple of days later.  While installing the sway bar, we threw in one our larger volume diff covers.

All of these parts wouldn€™t really make much difference unless we could lower the car and stiffen up the suspension. This is the one thing that I don€™t like about the 2008 car, its€™ soft suspension.  This might be because I am used to driving cars with stiff suspension, and it had been a while since I had been in a WRX, but either way its too soft.  But that is a good thing as this gives us something to improve upon.  We are a long time dealer for H&R, so we turned to them for coilovers. Of course there is nothing off the shelf that would work so we had them send us a few kits to try to make something work. In the end the exact combination of parts is kept secret, but it worked out great. We could now lower the car to a level that was functional, and looked great.  This is when the car really started to look good, and really started to handle good.  The suspension was dialed in, except for an alignment.  While you should never lower a car and not get it aligned, time was becoming an issue, and it just wasn€™t going to happen.

build_08wrx_hrwrxrearcoilassemblyThe custom built H&R coilover all assembled and ready to drop in!

These really look sweet on the car!


I know, its not the most glorious picture, but this is a nice feature of the new 2008!  Now instead of lowering a car in under an hour, i am thinking under a half an hour.


So what would power our PERRIN show car?  Of course we would not be showing off our car with a stock turbo, or stock location turbo, so the obvious choice is a PERRIN rotated turbo kit. But which turbo is the question.  If look at the internet, everything is about the GT3582R turbo. While this is a great turbo to make big power with, and it gets lots of press because it is a widely used BIG turbo, its not my personal choice.  The last two cars i had were very responsive, and i had grown to love that.  There was no way I was going to go with some laggy GT3582R, that is no fun and makes for a crappy autocross/street car.  The GT3076R is another very popular turbo, and we have built plenty of these kits on cars, so that is a boring choice. The turbo for me is the GT3071R, a bit smaller, bit more responsive, and still able to make 400WHP.  We always tell people that buy the smallest turbo that supports your HP goals, and while our show cars never really follow these guidelines, this one would be!  We would showcase the power that can be made on pump fuel and then on water injection.


Installation of the turbo kit involved creating a new downpipe which is longer and modified to clear the fire wall. This change in the downpipe also makes for a turbo fitment for the Legacy GT, so be on the lookout for that also.  The single most important part of the turbo kit changes was adding a CARB approved catalytic converter to it.  Another important thing we like to do is prove that you can make power with cats.  Many people out there think that the only way to make power is by getting rid of cats.  This is not the case and with our last couple of PERRIN project cars, we had cats installed, and they both still made great power.


With the rotated turbo kit being installed on the 2008, we quickly discovered that the intake system had to be completely changed. So a few 3″ bends, welding, and more of that red wrinkle finish! Like our other new turbo kits, the filter was located in the fender well area to get the freshest coolest air possible. This is another theme you will see from us. More cold air intake systems.  But before we go and build that, we need to finish the front mounted intercooler pipe to ensure it all fits together.


The starting point to the FMIC is getting the intercooler mounted to the car.  Starting with a Legacy bumper beam from our LGT intercooler, I quickly found that this wouldn€™t, although it was close.   Couple of simple cuts, some welding, and beam done.


In order to get the intercooler to fit, I had to modify some of our WRX tanks to allow it to fit tighter to the beam.  I just grabbed a set with no holes and redrilled them where i needed it.


This is an angle most people don’t see with our intercooler tanks.  Notice the nice smooth insides, not gonna see those ever again!




With the core mounted to the chassis, plumbing was next.  Every tube on the 2008 WRX FMIC is completely different than any of our other FMIC€™s, and in an effort of time the prototypes we made would have to be made to look like the final product.  A little welding, grinding and off to the powder coaters they went.  But before they left we finished the turbo kit intake piping and sent all of it out at the same time.  A week goes by and they showed looking perfect, STI wrinkle red!





Now we can finish the intake system! Just like the boos tubes, the protos had to become the final product, so more welding and grinding!




Its a tight fit, but the filter does fit down there very nicely.


Of course to support the potential power, we need fuel.  We would be using our high flow fuel rails and modded injectors.  The modded injector thing still is not very well acknowledged in the Subaru world (even though they have been around for a few years).  We have had very good success with this simple and very effective way to increase the size of the injector, so like the last 5 cars I have built this one would be using them also.  The 2006 WRX+ injectors are a top feed style that in stock form flows 540CC/min of fuel.  But like all the other Subaru top feed injectors, these for 800cc/min when modded.   Many people claim that these injectors have bad spray patterns, and cause poor fuel economy. This is just not the case, and people that tell you this are people that have not used them before. Then of course the good old Walbro Fuel pump would be used in place of the OEM fuel pump which probably doesn€™t flow enough to make anywhere near 400WHP.

With the intake manifold removed, and rails installed, it was time to install the fuel pump.  Should only take an hour, right?   Above I mentioned that Subaru moved the tank under the seat but this was discovered during this part of the installation. First I pulled the back of the car apart to find that Subaru shoved all the emissions stuff where the fuel pump used to be. This is where I found the pump under the seat.  Take note that, before you install a fuel pump, make sure that you just didn€™t fill up the night before. This is messy!! But it does make the shop floor really clean under the car!

Now I have not done an install of a fuel pump on a legacy GT, but how hard could it be??


Well it all would have worked out just fine, but the only pump we had I broke off the nipple from the output fitting, while installing the o-ring adapter from the OEM pump.  Since we didn’t have one sitting around, and we were strapped for time, we would be putting the OEM fuel pump to the test!  Could it do 400WHP??


The only way this whole car will run is with some good engine management.  We turned to Hydra again for a custom made ECU for the 2008.  Andrew sent us 2 harness to try out on the car.  The first one was a harness that completely did away with the OEM ECU.  This would have worked fine, but all these new cars have immobilizers which will not let the ignition switch work without the OEM ECU being turned on.  So the second harness was a special pass through harness that kept the OEM ECU in place.  I created a base map using Hydra€™s 2006 WRX base map and a fuel map from tune a long time ago.  The car fired right up and it was time to take it for the maiden voyage!


The Hydra has a MAP Sensor built into the ECU itself, so it was necessary to run a hose into the car.





The Hydra is installed in the glove box, and the pass through connector is under the carpet.



The car was finally done, and with a couple days to spare. Now it was time to pack and get some sleep.  Wait, there still is the outside of the car!!  When ever we do graphics on a car, things just seem to work out.  Digital camo seemed to be a popular thing this year, so lets do something like that John Herring said.  This goes great with the shirts he just made and should be pretty cool looking.   John started cutting out random square shapes a few colors, and things just started falling into place.  We used matte black, glossy black, and red.  As shadows appear, and the lighting changes, the 3 different colors change and produce a totally different looking car.  While these pictures show the basic sceme, they don€™t show how cool it looks in person.


And just like most projects on a tight time schedule, we got her done just in time€¦..except for the tires.  While we carefully watched our tracking number for the tires the week prior to leaving, we started to wonder why they hadn€™t moved from California for a few days.  A quick call to Yokohama, and they said they screwed up and had to Next day air some tires.  No problem, it just meant the day before we left, we would be running down to Americas tire and getting some tires installed on our Konig Wheels. While we patiently watched the tracking number again, Monday comes and nothing!!   They didn€™t get picked up until Monday!! DAMN!  Ok, this just meant, we would be getting tires mounted the day we were leaving. Ok, its tomorrow, we are all stress out about the trip, and again we are watching the tracking number (not very confident in what its saying).  After the 3rd Fedex truck, finally tires!!  Wait, how many tires does a motorcycle take. Ya, TWO tires, that is what we got!!  Alright, this is not good.  Again there was a shipping issue with the tires and 2 more were shipped out but this time shipped to an Americas Tire in Las Vegas.  We would just have to have them installed there once we rolled into town.

Since we left about 12 hours later than we wanted to we decided to drive straight from Oregon to LV without stopping in Utah like we always do.  The rest of the story is pretty boring until we finally got to the track.  We went into this event knowing that we were not there to win, but rather test the 2008 WRX, and show it off to the public.  I think we did a good job, as finally I started to hear people say €œI can€™t belive that is the 2008 WRX!€.  Proof that we did a good job of building the car.   With the worry over regarding what the public might think, a new worry was starting to churn my stomach. TRACK TIME!!




You might think that we have time to do lots of track days every year, but this has not been the case for the last few years.  While I wasn€™t really worried about crashing or anything like that, I was worried about the car and how it would perform.  Mainly because there was no alignment, no one had a tire gauge or pump, and the ECU was only street tuned with a few full throttle runs.  Because of the state of tune the car was in, and those things said, overall the car felt great. It was pretty fast and running 16psi of boost it felt like a 350WHP car, and spooled around 3700RPM.  I was pretty happy as we  I could tell there needed to be an alignment.  With visually 0 to 1 degree of negative camber, and who knows what toe in or out it had, it had mild under steer in the tight twisty corners of Spring Mountain.  The car kept up with some of the faster EVO€™s and other random cars at the track.  For a session or 2, I was going faster than an Ariel Atom, but I think he was taking it easy, as this car should have blown everyone away.  Over all the car was pretty fast, but bringing the car to a haltNow with some seat time at the track, and a new alignment, this car might be somewhat competitive.  Maybe you will see it at the upcoming Redline Time Attack.

After the event, we felt great that the car was very well excepted by the public, and that it did just fine around the track.  But like all events, nothing ever goes perfect, and the only real issue we had, was a box in the trailer coming loose and landing on the car.  Bummer!  Our good buddy Jason can take care of this no problem.



So how much WHP did our car make at the track??  Just before we left, we took delivery of a dyno (yes its been a long time coming), but there just wasn€™t time to set the car up and do a base run, so it would have to wait until we get back.  Well we are back and the results were very surprising.  As expected the GT3071R makes a little less HP than a GT3076R, but spools quicker.  This was the reason why I chose this turbo, better response for autocrossing and normal driving.  The car makes almost 340Ft-lbs of torque, and 320WHP.  This was at the 16psi we ran at the track, and no wonder why we were keeping up with cars we thought were way faster.  When tuned to 18psi we made 365WHP, and 375ft-lbs of torque, while this is a good safe place to leave the car for engine durability issues, we have to push the car a little to see where this turbo starts to loose its breath.   At 21PSI, we made 385WHP, and 390FT-lbs.  Plenty of power for a street car!




Besides wait for an STI to come our way, this car needs a wing badly!!  Wait till you see what we have in store!!  Besides the wing, the car needs a little more love to get the suspension dialed, and I think its ready for more competitive track time.  We will just have to wait an see if it makes it to the Redline Time Attack!


While all these parts were created for our 2008 Show car, what would we be building for our catalog of parts??  Well, everything!!  All of these items along with our normal mix of parts are all in development and should be ready by the end of the year.  This is of course the new parts that had to be created, but there are many current parts that fit the 2008.

What did we have already for our build?

Front swaybar, front end links, fuel rails, injectors, PSRS, downpipe (for stock turbo, but not used), R160 diff cover, WRX short shifter, Shifter bushings, Crank pulley, EBCS, VTA and Recirc BOV€™s, gauge pods

What did we have to build?

FMIC, turbo kit, rear swabyar, rear endlinks, turbo back exhaust,

What parts we plan on making.

Sub frame brace, rear diff lockout, rear control arm bushing replacements, intake systems for OEM turbos, PERRIN custom tuned AccessPORT systems,

Parts installed on our show car.

FMIC, turbo kit, exhaust system, intake, PERRIN parts installed
PERRIN 2008 WRX GT3071R rotated turbo kit
PERRIN 2008 WRX Rotated turbo intake
PERRIN 2008 WRX 3€ Turbo back exhaust system
PERRIN 2008 WRX Positive Steering Response System
PERRIN 2008 WRX 19mm sway bar
PERRIN 2008 WRX Endlinks
PERRIN 2008 WRX Short shifter and Shifter bushings
TIAL 44mm Wastegate
Custom Hydra standalone ECU
Custom H&R Coilover
Konig Feather black wheels
Advan Neova 245/40/17s

Look for more information about the 2008 over the next few weeks!  Feel free to call us with any questions about 2008 Products or fittments.


 Posted by on October 17, 2007 Project Builds Tagged with: , , , , , ,
Aug 172007

This is an Nasioc Post we made regarding our older T31 turbo kits and changes we made to make the kit better.


First off fitment issues with the PERRIN turbo kit, are not common. While we have had issues time to time, we have taken care of those who had them.  I should say we have taken care of those who have called us and explained their problem.  There are a lot of our kits out there, and of course when there are problems, people say €œHey I have a problem€, weather by calling or by posting on forums. Those who don€™t have problems, generally go happily on their way, and never say a word. So while it seems like a lot of kits don€™t fit, this is just not the case.  We have many many satisfied customers and dealers who have complimented us on our kits, and how well they do fit.

While this is a hard part to install, we do get calls and comments about parts that are not fitting together well.  Generally the customer just hasn€™t adjusted something correctly, or installed things out of sequence.  To combat this we have changed instructions, and how the kit is €œpre-installed€, which has help quite a bit.  Secondly we have taken extra measures to ensure each kit fits together perfectly before it leaves the building. This means that the uppipe and DP have both bee fit together to a turbine housing and to the WG to ensure all pieces mate together properly.

Complaints of fitment with WG v-band are very common.  This is because this connection is very, very precise and it being off a little is very easy to spot.  This concern is easily fixed by customers following the directions and preassembling the kit outside the car. Then you are not dealing with trying to fit and align it in tight quarters.  As much as going to a 2 bolt type flange or WG would solve some problems, this is not something we are going to do.  The compactness, and performance benefit of the larger 44mm WG is well worth it.


Originally we made our kit somewhat universal to other FMICs.  While the connection from the turbo to the FMIC can be made, it was a little tricky to get just right.  With our current kits we are shipping we simplified this quite a bit with a single Silicone hose that goes from the turbo to the FMIC connection. This Jog eliminates extra couplers, and pipes that caused some issues.



Lets go over a couple things with the housings.  Like I have said many times before, and have shown many times before, there is no difference in the housings.  We choose to use the housing we did (a long time ago), as this housing was much more compact, and was readily available from our turbo supplier. These are the T31 exhaust housings people are referring to. These housings are a T3 inlet and have a short 2.5€ outlet.  The newer Garrett GT housing has the same T3 inlet but a longer 3€ outlet.  With out saying anymore, people jump to the conclusion that the 3€ is better as it is bigger, because in a turbo exhaust system bigger IS better.  You have to look at both housings and understand what makes them different, not better.  First off the turbine wheel inducer for all these turbos are smaller than 2.5€, which means that in order for it to get to 3€, some flaring is done.  Its in this flaring where things vary from the T31 to the Gt housing.

The T31 housing basically has no flare (inserter Office Space joke here).  The end of the turbine wheel is very close to the flange where the DP bolts to.  Our DP bolts to this and starts at 2.5€ then quickly is flared to 3€.

The GT housing is very long so it goes from the turbine wheel to the 3€ oulet in a couple of inches.  Basically accomplishing the 3€ OD in the same distance as our kit with the 2.5€ outlet.

Since we have a Garrett Engineer assigned to us of course I proposed the question whats the difference, his exact response below.
€œWe have never run a test between the two housings for that exact turbine
wheel.  (I asked hims specifically on the GT3582R ) We did do a test a different turbine wheel and the performance for the 2.5″ housing was slightly less (on the order of the uncertainty of the measurement).  I would suspect you would observe no performance difference.€

Add to that are some pictures showing the differences:




Proof is in the pudding!!!!!! (Not sure where that came from but I am sure Wikipedia has something on it) There are a couple of naysayers out there about this housing, but they are not comparing apples to apples.  If this housing was so bad, then we would see some HP or spool differences in cars with GT housings, but this is just not the case.  We have cars with Gt3076R w/.82 turbos and they spool around 4000, and make about 400WHP on pump gas, and 460 on race gas.  This is the same thing seen on the GT housings, and in fact a somewhat local customer had one our kits modded for the GT housing, and his car spooled just like others, and made about the same HP as others.  If this T31 exhaust housing was a choke, or a hindrance to the WRX€™s making power, I think there would be a lot more people complaining about how their car doesn€™t make enough power.


Regarding the support brace. This is a part we have developed a year or 2 after we release our kits. The brace is a very simple and effective brace that limits the €œpossibly€ damaging left and right vibrations.  We say possibly as there are many turbo kits out there with no brace and have no issues.  Because of the way the kit bolts to the car, it is somewhat braced in its self. This is why so far, there is no need for one.

We currently have braces in stock for the old GT35R, but since our kit is changing, we will not have braces for the other turbos for a while.

That should clear up peoples concerns about the kits performance and fitment issues.

The Changes!

Now onto the changes we have and are making.  We are switching to the GT housing!!  Since there are those who €œThink€ the T31 is not as good as the GT housing, what better way to satisfy everyone than to change to the GT housing!  While we feel there is ZERO benefit in HP or spool, the other benefits are supply issues.  Since the inception of our turbo kit, we have gone direct with Garrett, and getting the newer housings is much easier, as they are an off the shelf part.  So switching housings forces a few things like DP and uppipe changes, which we have added more room around the WG, and clearance around the chassis. While our kit will hang a little lower, it will eliminate any issues with clearance with different motor mounts or slight variation in cars.


Blow thru boost tube

This is a part we have been selling for a while now, but it is change to the new kit because you HAVE to have it (or a stand alone ECU).  We have found that this part makes tuning simpler, eliminates issues with stop and go traffic (making the MAF see high temps), nearly eliminates rich or lean conditions with leaks in boost tubes, or intake hose.

Intake system.

This is an item that was made for this future kit, as well as the old kit.  No more silicone!  Well at least big pieces of silicone.  The new intake system is now a cold air tube that fits down in the fender well.  While this part is a little trickier to install, it really cleans up the engine bay.


I like guys at Crawford performance, and in no way do we say they make a bad part.  Both of us have great parts that fit people€™s needs. Their kit requires their FMIC, ours fits with our FMIC and other OEM turbo fitment types.


Your spool characteristics are probably right in line with what you would have had, if you just got a new turbo from us.  Clark makes it seem like there is some huge difference, and this is just not the case. But going from a 4000-ish spool and adding 800-ish isn€™t that much different when it comes down to it. Also with the hit of power you have, it makes up for that loss of power right before the boost comes on.

Remember the T31 is a Garrett part, and its machined to fit the volute and the profile of the turbine wheel just like the GT housing.  I agree that it would be nice to put the T31 housing debate to rest, but it will go on forever, as long as people keep using them.  Your statement about why would Garrett come out with a new design is a good question. But the answer is simple. They had more demand from the gasoline performance world wanting bigger 3€ oulets to make it simpler to build exhaust systems.  Garrett didn€™t change it to increase spool or performance.  Yes, Garrett really pushes their new GT turbos as better spooling but this is because of change to Ball Bearings, not a change in the housings.

You definitely had a kit that wasn€™t correct. And like other people we would have taken care of you had you called us. I am sure you understand that, and I too understand that sometimes you just can€™t wait. You€™re in the middle of the project and something happens, and you just deal with it.  Especially on the weekend, this is not something that can get fixed and it can be frustrating.

Regarding some of your CONs of the PERRIN kit.
We will never use a bellows anywhere on the kit.  This is because they do not hold up to the temps and pressures seen before the turbo, or at the WG dump tube. We looked to using these a long time ago, and no one would guarantee theirs would hold up under 1600 degrees+ and deal with the pressure.  Using one after the WG dump is an ok place, but it is not needed as the catbacks contain the flex.

The filter is a tuff one.  If you understand how they work, there is no reason to have K&N on your mind.  If it is a looks thing, well we are changing something there.

The oil drain is pretty simple, a flange, fitting, and hose connecting it to your OEM drain.  Getting it nice and smooth is easy.  This is not something we have had issues with.

Flanges welded to the outside. This is something we well also not change.  Welds on the inside of the pipe or butted up to them, do not have very good support.  The tubes will have better support if fit tightly to the ID of the flange, then welded on the outside.  Welding on both sides is really bad with Stainless steel.  This is because SS shrinks when you weld it, and it can cause stress on the weld when welded on both sides.

Regards to no BOV. I know where they got this info.  At SEMA a couple years back Precision turbo was next to us and it came up in conversation. I thought they were nuts, but whatever.  I asked Garrett about this, and while their new turbo can take 10 times the force of the journal bearings, but that doesn€™t mean you shouldn€™t use a BOV.  Also they have as part of their warranty questions are they using a BOV or a functioning BOV.

Now a couple of situations come up when a BOV is not necessary.  A race car that does 99% of its shifting with flat foot shifting. In this situation, the throttle never closes during shifting, so there is no need for a BOV.  The other situation is low boost.  Say up to 5 or so PSI, a BOV is not that necessary. At this point the 5psi of back pressure trying to stop the turbo (during shifts) isn€™t that bad for the turbo. And generally an engine/turbo running 5psi is pretty responsive so re-spool isn€™t a problem.

But you still want to use one in any Subaru application. They run too much boost, and if you want your turbo to last as long as possible us a BOV.  While not running a BOV may be OK on a turbo, its not good for respool. That sound is the air backing up in the boost tube going through the turbo. At the same time, your turbo is either stopping or really really slowing down.  Also this rush of air going backwards through the system will cause bad MAF readings and poor drivability at low speeds.

Using Crawford as an example may not be the best as all of their shop cars are race cars. They don€™t even need a throttle plate!  But it is very interesting that they have gotten good life from their turbos.


 Posted by on August 17, 2007 Forum Posts, Part Design & Tech Tagged with: , , , , ,
Aug 172007

First let’s start with the car. I am not going to get into the stats of the car in stock form.  Its by no means is it the fastest car, or the highest G load car, but it does everything pretty well, especially handling and feel.  I have owned it for almost 2 years now and has been up for sale 2 times, but never sold.  Mainly because I didn’t really want to get rid of it!  Well I decided to sell to the STI as the new model was coming out, and there wasn’t much let to modify on it.

So I started looking at the little red car in the garage.  Over the years, my wife mainly drove it, and I put up with some of the little things I didn’t like.  There was really only 2 things I didn’t like, the power or lack of power, and the placement of the pedals.

I am big guy, 6’4″ and way more than 200lbs. So this little car isn’t something that really fits my physic.  When I was falling in love with the car, the only concern I had was can I fit.  Believe it or not, there is plenty of head room for me. Leg room…..  well its not perfect.  But most cars I have owned (except the Mini) don’t quite have enough leg room.  Over the next few months, I started to tweak the pedals, closer to the floor to allow for more room. Well after some simple adjustments, it was nearly perfect!  Nearly, as the clutch pedal wasn’t really adjustable.  I saw a way to adjust it, but I had to remove the clutch master cylinder and space it from the foot well. Sounds easy on a normal car, but on the Elise, it’s a little tricky.  The only way to get to it was to remove the front clamshell.

One thing I really found I love is how simple yet technical the car is.  Things like the body panels, suspension, chassis, are so simple in their construction, but at the same time they are very technical in the way they are made and designed to work together.  While removing the front clam might be easy and the clutch is something I want to adjust, I have Horsepower on the brain!

Like I said, it’s a fast car, but it could use another 50-100HP, and it would be perfect.  So, how to get 50-100HP??  There are supercharger kits and turbo kits available for the lotus, so which method??  Supercharger kits never really get me excited as they are expensive parts by them selves compared to turbos ($3000 vs. $1000) and they cost you HP to drive them.  A SC kit requires a lot of off the shelf parts, where a turbo kit requires more custom parts, all of which are things I can build myself.  Some argue a SC is more responsive, as they build instant boost.  For a light car like this, a SC would be a very good, but expensive option.  But, comparing an engine running the same boost, the turbo (when sized properly) can be just as responsive, and make more HP than a supercharger.  While the high compression engine is controlling the limit on HP, it also helps to make a turbo spool up quicker.  In the end, the right size turbo will build more boost at lower RPM than the SC, and it will not have the 20-30HP of drag on the engine.  I think the obvious choice is the turbo.

Like I am going to buy someone else’s kit, when I can make it myself!


With my experience with turbos, and a few calculations of engine air flow at different boost levels and RPM, I mapped out a few Garrett compressor maps.  There are about 3 turbos, or basic turbo sizes that I had a feeling would work well.  The GT2554R seemed like a good turbo, as does the GT2560R, and GT2860R.  The GT25 turbos will spool instantly, but the high reving, and high compression motor, needs to breathe!  Both the GT25 turbos have a very small turbine wheel, and while these will make the power I want, they could cause high exhaust back pressure and cause an increase in EGT’s.   The GT2860R turbo might be a little laggy compared to the other smaller ones, it should still be responsive enough to build boost before 3500RPM.  When the turbo will spool up is kind of a mystery until we can fire up the engine.  Because I rarely drive the car below 3500RPM, the GT2860R is the turbo of choice, or is it??  There is another turbo Garrett makes that is very similar to the GT2860R, that is the GT2860RS (Disco Potato).  The RS is rated for an extra 60HP, and is known by many to not be much less laggy than the R model, but make more power.  The difference in the turbos is the trims of the compressor wheel and turbine wheel. The larger trims make the turbo flow more air, and be freer flowing.  We just happen to have one of these sitting around the shop!  Along with a few others:tech_turbo_2lgt2554r_471171_3_comp_e





In reading about the turboed Elises out there, I see that some people have boost creep problems.  All the turbo kits use internal wastegates with small ports for bleeding off exhaust pressure, which could be part of the boost creeping problems.  So an external wastegate became part of the turbo kit equation.  External Wastegates have very large ports to bleed off exhaust pressure, plus they look way cooler when installed!  These are also parts we have sitting around the shop.

Engine Managment

In order to run the engine with the turbo kit, good engine management would be necessary.  Again, reading about the other Elise turbo kits out there they all use crappy EM to run the car.  Piggybacks, reflashes, all of which rely on someone else’s tune. Not to mention are known for blowing up a few engines.  This just doesn’t cut it for me.  So I turned to Hydra EMS, who I have used for 3 other project cars. They offer stand alone, plug and play ECUs for many cars one of which is the lotus.


The HYDRA has to be installed in the trunk. This requires re-pining the harness, drilling a hole and running a vacuum hose.  Not a big deal, just takes some time.  Before I go installing the turbo kit, I installed the Hydra and got it running in NA mode.  Tuning the Hydra is simple, and I bought the integral Wide band 02 sensor with it that allows logging to include the wide band and the auto tuning feature to work.  While the wide band 02 sensor allows for the auto fuel tuning feature to work, its not good enough to get the car fully tuned.  But it helps to get you close.



With any turbo system a good large diameter exhaust is needed.  Before the turbo kit goes in, I built a 3″ single muffler exhaust system.  While a bit loud and large for the NA engine, the 3″ exhaust, it would soon show its worth, when the turbo kit is all done.  I used 3″ 304SS tubing, and a straight through 3″ round muffler.  I had an old High flow metallic cat lying around which I also used to not only be emissions friendly, but to keep the sound somewhat in check.  This header back exhaust design utilized the OEM flange with donut gasket, so it could bolt to the factory header.  While this flange was a temporary until the turbo kit was done, it would serve as a good starting point for the turbos’ exhaust system.


So I have the turbo, wastegate, tubing and the other basic components to start building the turbo kit.  Now its time to pull the back of the car off to plan where its all going to go.

I looked everywhere on the net for some how-too’s on removal of rear clam. They just don’t exist. So no big deal, just means I will have more fun doing it. First step is removing the battery, battery harness, and tail light harness from the trunk. Once this is done, there are 4 screws that have to be removed that hold the rear clam to the chassis.  Since I built a rear panel eliminator, there are only 3 other screws that have to be removed from inside the trunk.

From there the quick and basic steps are:

Remove the wheel well liners, remove the bolts holding the body to the rear diffuser, remove the seats, remove the plastic rear speaker shroud (careful of the speaker wires, and the proximity sensor, remove the 4 nuts holding the trunk lid pivots, remove trunk lid, remove the upper roll bar cover, remove screws holding body to roll bar, remove plastic roof latches from body/roll bar, remove 2 bolts on each side of body where the upper clam meets the lower body (2) on each side,  Removing all the obvious bolts and screws are easy, but there are 2 hidden screws that are not easy to find.  These are located behind the seat belt tensioners toward the outside of the car.  All of these bolts are 10mm head bolts with large SS fender washers behind them. With the back of the car removed, I can now start figuring out where the turbo can go.


With the back of the car remove, the car looks kind of cool!  Maybe i will leave it like that…..



Now being realistic!

While its no fun my wife had to go on a trip to China, and my step son vacationed at my dads house, it gave me 2 weeks to finish the turbo kit up!  I already have the Hydra installed and running, so when I get the turbo kit done I can fire it up right away!

With the exhaust system built, Hydra installed, and rear of car removed, it was time to start planning where the turbo will go. I decided on using the GT2860RS with an external Wastegate. This turbo is very small and compact, and will be very easy to fit behind the engine.  I purchased a ½” thick Laser cut flange for the head to start with, and bolted it to the engine. From there I used

I had to reinstall the rear body a few times to make sure things cleared body and chassis parts. Once I got the turbo sittin’ pretty, I built a little jig, by welding some 1/2″ SS rod to the header flange and turbo flange.  This allowed me to remove the “Header” from the car and start putting together the primaries.

Choosing the primary size was easy as the flange ports were 1.5″, and this would be plenty big enough for the HP I would be running.  To ensure it would hold up for a long time, I made sure it was .125″ wall.  This thickness ensures that vibration, and the weight of the turbo will have little effect on the durability.  This thicker material is also good at heat retention       so once heated up it will help keep exhaust velocity up.

With the jig off the car, and few days of working after work, I had the header completed.





To keep the part looking good, and to add some function I decided to ceramic coat it.  I had used some VHT header coating in the past with great success, so I decided to use it once more.  This coating is $8 a can and one can, will do the trick. The only important thing is the header has to be scuffed up a little to ensure the coating adheres to it properly.


With the header nice and roughed up, it was time to coat it. The coating turned out great!  The trick is to make sure you do a lot of light coats, while not going too thick, as this can cause it to crack after the initial heating process. I used the black colored coating as it is a very clean look. It was pretty barried in the engine bay, so I could care less about it being all shiny and polished.




Upon completion of the header, I noticed the flange was not so flat anymore.  I tried to make sure to not use too much heat while welding it together, but SS really likes to move when welded.  To ensure it was not going to be a problem, I had it ground flat.  Of course I didn’t notice it until AFTER I coated the header, hence the black header with a shiny header flange.


While I was in the mood for painting things I decided to paint the compressor housing of the turbo.  Again, turning to VHT for some more paint, I ended up buying a couple cans of wrinkle black and wrinkle red paint. This stuff is also awesome paint.  I have used this on the H6 project, and on a couple other random things.




With the turbo mounted, it was time to adapt my exhaust to it.  Toyota was nice and used a bracket to help support the OEM header, and I decided to utilize that to help support the turbo.  It worked out perfect to build a bracket onto the flange for the turbine outlet. Next was getting from this flange to the exhaust I already created.  Since I have to cut of the OEM donut flange off the exhaust, I had to replace this with a flex joint. From there it was easy, a V-band flange, some bends, and polish it all up, weld it together, and bam!




With the Exhaust system short, free flowing, and polished up, it was time to think about the External Wastegate, and how it would fit into the equation.  Like other parts of the build I wanted it to look good, and be functional.  Why not put it behind the turbo at the back of the car where it might be seen. Plumbing the WG dump tube back into the exhaust was something I really wanted to do, but upon inspection, things were just too tight.  It had to be plumbed into the exhaust before the flex joint, and there was just not enough room to do that.  So I vented it to the atmosphere. Normally I would shy away from this as it can be very loud, but who knows, running 5-10psi of boost may not make much noise anyway.  Using the hole in the rear diffuser where the OEM tips came out sound like a good idea.build_lotus_externalwg




Now that the turbo is setup to breathe, its time to build boost tubes, and the intake system. Starting at the turbo, the intake was first. This was pretty simple, a PERRIN air filter stuck to the turbo inlet, done.  Yes this isn’t normally the best place to put an intake, but on the lotus engine, there is no extreme heat it would be seeing. The block is right in front of it, but also is the suspension and lots of ambient air flow.  Routing the boost tubes to the intercooler is going to be tight, but doable. Before I get that far i have to design the intercooler, and decide where it can go.

The first thought was to use one of the side scoops for the fresh air to it.  Looking at many of the other turbo kits out there they too use these scoops. The only problem is none of the are very large, and none of them are in a very good place. They also have to use helper fans to make up for their small size or poorly mounted location.  There is no way that helper fans are going on my car!


I used the drivers side scoop and started to lay out where the IC can fit.  I ended up using part of a Legacy GT intercooler we had sitting around. Using what little space there is in the scoop area, I ended up basically resting the IC on the fender liner.

Now that the core has a nice place to sit, time for end tanks. I started with some 4″ tubing and cut it in half to create the end tanks. From there, I cut some caps out for the end and welded an inlet tube and an outlet tube. To ensure it got good ambient flow from the scoop, I built a shroud around the intercooler to direct the air through the core.  Other intercooler setups I have seen just let the ambient air flow around it. This is not good.


With the shroud all welded to it, I wanted the intercooler to look like it was supposed to be there, so like other parts, I painted it.  This time I used the black wrinkle finish.  As you can see from the pics, it looks OEM.



With the intercooler in place, building the boost tubes was easy.  With a few bends here and there, a MAF sensor, flange, some time on the polishing wheel, and now then engine can finally get some boost.

I can’t forget the blow off valve!  This was an easy choice, I used my trusty PERRIN signature series BOV #000. Its been used on my last 3 cars, and still working great!  Instead of the normal silicone coupler and a couple of hose clamps, I used one of our universal adapters, and welded it to the boost tube. This allowed me to screw the BOV to the boost tube.


With the main parts installed and nearly ready to fire, it was time to give the turbo its vitals, oil and coolant.  Getting coolant was easy, I just used the coolant input on the overflow tank, and ran it to the turbo, and back to the tank.  This provided great flow, and reasonably cool temps for the turbo. The oil feed was a little tricky. No one really shows a good picture online of how they hook up. The backup plan was to unscrew the oil pressure sender and tee into that. Upon further inspection, my car has the dual oil coolers and a nice sandwich plate.  Bingo, perfect fitting at the 12 O’clock position!   The sandwich plate has a bleed fitting to help get oil out of oil coolers during an oil change. I just used some -3 SS Teflon hose, and some speed fittings. These allowed me to custom make the hose in the shop and not have to go down to a hydraulic fitting store.

Once the turbo gets oil it has to get rid of it. Again the simple solution is tapping into the oil pan. Once removed, I welded a small SS tube into the side, and reinstalled it. Now that makes it sound easy, but I spent about an 2 hours on this part alone.  5 minutes to weld cut the drain, and rest of the time getting the dump pan off!  The OEM use of RTV is nuts!  I am not even sure why there are bolts holding it on!

To ensure all the oil and coolant lines never had a problem with melting, I used quite a bit of our PERRIN Pyroshield to cover everything.  This cover is good to 2000 degrees, and keeps the internal hose under its melting point. This ensures that there will be no issues with hoses melting or blowing off.




Because I like to build things myself and not buy other peoples parts, i wasn’t sure what I wanted to do about the injectors. I could buy some, or I could try modding them.  We learned this little trick with the Subaru injectors, where you can remove the small screen on the end of the injector and get them to flow more fuel.  The problem is we have never done this with the Toyota injectors, so how much will they flow????   First off they are a Denso part just like the 2002-2005 WRX injectors. In theory, if they use the same basic injector, and just change the screen to flow different rate, these should flow about 800cc/min.  So after carefully modding them, sure enough they have the same ID where the pistons lifts from, and they have the same lift!  PERFECT, I don’t have to go buy injectors that may not fit or may not plug into the injectors.

Along with the injectors, i got a set of Brisk Spark plugs. While most people have never heard of them, they make a really nice part. The set i used are the silver racing eletrode plugs. These are a better plug than the iridium for power, but  not quite as long wearing. But who needs plugs that last 100K miles!  This item is something you will see us selling very soon!


Well after a year of driving and a year of somewhat hard driving the rear tires are toast!  Stock the tires are 175 fronts, and 225 rears.  While this is a small light car, and those sizes will suffice…… who want to suffice!!  Again back to the forums for some insight as to what can fit.  195s on the front and 235s on the back are common upgraded widths, but can that be pushed???  So 215s on the front and 255′s on the back were just going to work!   Now to pick the tires!  The ultimate street tires in my mind are the Yoko A048s. But they are expensive, and don’t last long, but grip like crazy when warmed up.  John Lietl over heard me thinking of new wheels and tires and said, “hey, you help me build my Evo turbo kit, then I’ll give you my A048′s”.  I had to ask to make sure he hadn’t gone out for beer at lunch but sure enough, he had a set at home, and an EVO turbo kit was on the PERRIN-Evo-parts-to-build-soon list. We have a deal!

Wheels while easy to pick out, are very hard to find the right offset.  Custom ones can be made, but in the end there were 2 pretty good choices I found that fit.  The Team dynamics pro race, and the PIAA FR-7, look great come in the right sizes.  I went with the TEAM Dynamics wheels as their price, and availability was perfect!   Semi gloss black 17×7′s and  17×8′s replaced the 16×6 front, and the 17×8 rear.  I think the biggest change is in the front wheels and tires.  The OEM fronts look like front wheels from a street bike compared to the new ones!  This side by side comparison shows the change in contact patch.


After many clamshell installs, and test fittings, cutting, trimming, welding, trimming again, and polishing, it was all done, time to fire it up!  Since I had no map for the injectors, I had to build it. The Hydra has a really nice injector change trim feature which allows you to enter the stock inejectors, and the upgraded injectors, and it recreates the base map for you. I tried this out and removed some timing, just to be safe.  I hit the start button, and it fired right up the first time and ran great!  AFR’s were in check and it was time to let it do a few heat cycles to ensure coolant hoses and oil lines were all good. No leaks!!



The nice thing with high compression engines and turbo kits, is that they don’t loose power anywhere compared to the stock engine. Sure enough the car finally has some low end power!  With 5psi of boost, and some initial tuning, I was well on my way to getting the car tuned to 10psi!


Next to come is a Prototype PERRIN PWI-2 Water injection system, and dyno results!


Shout outs:


Hydra EMS

Team dynamics



Elisetalk forums

My Tig Torch

My wife

oh, ya PERRIN Performance!


Test and Tune Session…..Finally

I finally got around to putting up the dyno plots from the tuning session.  While i had been doing alot of road tuning before the dyno session, there was quite a bit of power left on tap.  This is why a dyno tune is important.  AFR Targets and watching for knock only get you so far. Having a great tool like the dyno shows where a specific AFR at a specific RPM makes more power. It also shows where different cam advance numbers make more power, which is not something you can see with datalogging.  While dyno tuning is not something that anyone can just go get done, on any turbo setup, i think it is very important to do.

So i know there are a lot of guys with Turbo, and SC packages, but it seems lately the buzz is all about Superchargers.  I am a big turbo fan, and i think that turbo is the way to go.  With a turbo setup, you get more boost down low, so more torque, and you don’t get the HP losses from the SC.  Overall a Turbo is more complicated to install, more parts and more expensive, but it is well worth difference!

Full Write Up on the car is located HERE

After a few weeks of road tuning(driving back and forth to work) i still hadn’t been able to determine where to turn the lift on.  I started at 5800 which is where alot of the tuned ECUs put it. This seemed ok, but not real smooth when it kicks on. I am sure many of you are thinking, did you tune it during the changes? Yes!  Of course. When tuning a car, you can just change one thing and expect results. There are many things to tune on the car to ensure that the changes you make are not waste.  I spent quite a bit of time tuning the car at 5800 RPM point of lift engagement.  3 things occured.  No matter what i did, a loss in power, and a rich condition.  Lastly the boost dropped quite a bit.  After leaning out this transition, adding timing, and even some cam timing changes, it never felt as good as stock.

For this setup, i am using the Hydra EMS plug and play ECU. This is a great tool for tuning cars, as the changes are instant, no flashing, its as simple as reading the maps, and the wide band, and making changes. Also it has great knock sensing capabilities, and feedback, so you can see where the engine is starting to get noisy.

Then i did some reaseach about the SC cars, and found that they turn the lift point on at 4500. So i did the same thing, testing this cam change over point, resulted in major low end power loss. Same thing, lots of fuel, timing, and cam timing changes, and it never was that good.  So with that said it was time for the dyno.


These are the first runs with the lift at 4500. As you can see, just like i felt on the road, a large loss in power.  Not to mention the huge drop in boost when it kicks on. The strange thing is, the Blow off valve actually blows off a little when this happens!  I experienced this same thing when tuning another project car of mine, the Subaru H6 project. The H6 Subaru engine would drop about 3psi when the lift kicked on (when turned on below 4000) and it caused a 100HP and 100ft-lbs loss in power!  Only the lift was turned on before 4500, it was fine. Same thing here.


After experimenting with the lift at a lower boost setting, the graphs finally started to smooth out. The Dyno we use is a Dynapack, and is very sensitive, which is why the “jitters” show up on this. We can see a 1 degree of timing change on this dyno, so its great for R&D, but not the best for producing Dynograph to brag from. It was time to turn up the boost.


So why didn’t the 4500 lift point work? Well on the SC cars, the SC is flowing a linear amount of air through the RPM range.  So when the lift kicks on the SC doens’t loose boost from different engine air flow  from the differnet cam profiles.  So the transition is much better.   Some of the reallly big turbo kit guys in the celica forums turn the boost on lower, but they also are using huge turbos that dont build boost until after that point.  Anyway, that is my guess.


So after all that, i ended up with the power i was looking for 260WHP!  The torque i didn’t really have a goal. I knew i wasn’t gonig to run too much more boost than 8psi, so the torque would be kind of limited. Still 190 ft-lbs, that is plenty to move this 2000 lbs car!


You can see the boost curve i started with and ended with.  The more boost we ran the more the lift caused a drop in boost in boost.  You can see how the high cam effects boost.  The lower valve overlap at lower RPMS helps keep boost in the engine.  The high overlap shows how when the lift kicks on that boost is getting blown out the exhaust.

So after all that, what you see is what i got!

The one thing that i wish i had done previous to building the turbo kit was do a baseline of the bone stock car. This just didnt happen, so all i can do is guess at the Wheel HP i had previously.  Best  guess i somewhere in the 160-170WHP range and somewhere around 110-120ft-lbs.

So i think most people want an Extra 100HP from there Elise, which gets it close to the HP per pound ratio of Vettes and Ferrari’s.  This is using CALCULATED WHEEL HP versus pounds.

PERRIN Turbo Lotus 7.6 pounds per WHP

C6 Vette 8.8 pounds per WHP

997TT 7.7 pounds per WHP

ZO6 Vette 6.5 pounds per WHP

Just something to think about when comparing this to other super cars.

After all this buildup, and dyno tuning, its time to sell the car.  Not sure of a price, but i am thinking somewhere around $40,000. Seems fair?? Not sure, but i have had the car 2 years, and its time for something new!

I would be happy to share anything about the build, or anything about the tuning of car.  We never made any parts for the Elise, so i am not here to compete with anyone, just sharing fun info!





 Posted by on August 17, 2007 Project Builds Tagged with: , , , , ,