Category Archives: STi

’11 STI dyno tune

Another new model STi came in for a tune the other day, and boy are the stock tunes dangerous. We have done multiple newer body Subarus and they always seem to run very lean & make disappointing power. After making a handful of adjustments this car went from a measly 220whp to 317whp. One of the best things about the tune is that its safe. We’ve seen to many Subarus come in blown up because of “off the shelf” tunes or people beating the cars hard without a tune. It is impressive that with only 3 power mods and a tune you can pick up 100whp!

Don’t hesitate to call us today to set up your tuning appointment! Thanks for watching.

400whp 30r ’07 STi

We had a longtime customer bring this car in for a pre-purchase look over. After going over the car we found that it had low compression in one of the cylinders and was breaking up while going into boost. The customer purchased the car afterwards and brought it back in for a base tune so it could at least be driven smoothly & safely while a plan for a full build could be laid out.

Once on the dyno a small bit of tuning got the car running smooth and clean throughout the rpm range. Surprisingly even with the low compression at only 20psi it laid down just under 400whp & 380wtq! The owner was extremely happy with end result.

Knowing the engine has some issues & won’t last forever, the new owner is preparing to build it over the winter and possibly make a few changes to the turbo setup as well in hopes of bigger power. Check back in the future to see what route this car decides to take, but for now enjoy the sights and sounds of this 400whp widebody hawk-eye.


600+whp PSI PRO built/tuned/fabbed STi video

Here at PSI PROformance we have done a few recent 4-500whp rotated turbo kit Subarus with great results. Some customers just want more, and we are here to make it happen.

We have modified this STi a few different stages since the owner purchased it and after talks of wanting more power he decided on a 600hp goal.

The project began with our custom-spec built/sleeved engine, and our custom rotated turbo kit. With the power goals in mind, a Precision 6262 turbo & E-85 fuel were chosen to make it all come together. With a host of supporting mods & custom built parts done in-house the car easily put down 600 WHEEL horsepower after being tuned on our Dynojet.

We have since installed a resonator to our Race-spec exhaust and the car is happily in the hands of the owner. We are looking forward to it coming back in for a re-tune on higher boost when the owner is ready. At only 29psi the setup is not even breaking a sweat.

The customer brought the car back a week later to have us add a muffler as he was getting dirty looks from annoyed neighbors.

Please check us out on facebook to see regularly updates photos from around the shop including the build of this STi. If you have any questions regarding the build, or would like to start a Subaru build of your own please don’t hesitate to contact us at the shop. Our number is: 215-361-7100

450whp+ Subaru STi base tunes

We’ve had a lot of quality built Subaru WRX, STi, & Legacys come through the shop lately. While some are the typical street car 250-300whp builds, here are two cars that went above the typical bolt ons. First up is a white 2010 STi hatchback that unfortunately had engine failure after running around on an unsafe Cobb Accessport off the shelf map. With only a few thousand miles on the clock the owner was forced to rebuild her. A built motor was assembled & installed, full bolt ons were added, and a Forced Performance Red turbocharger was purchased. On pump gas, conservative tuning, at only 22psi the STi put down 454whp & 407wtq after our tuner Steve took the helm with Open Source. He also set up the car on Speed Density which really makes a difference on the way these cars drive. We’ve said it before and we’ll say it again, if your running a Cobb Accessport do not beleive that the off the shelf maps are good for every car out there. Bring it in and have it custom tuned to your specific car and modifications. It will save you a lot of money in the long run, just ask the owner of this 2010.

Next up is a 2007 STi that the owner has been rebuilding and assembling for the last year. With the brand new built motor finally installed he had the car dropped off for a base tune so he could begin putting miles on it safely. Running a built motor, cams, full bolt ons, and a GT35R (with the beautiful Tial v-band hotiside) this car had us all excited. Not often do you see a properly built Subaru like this one. Considering the motor was fresh Steve did a safe base tune at 18psi which yielded 460whp & 385wtq on straight 93octane pump gas. We are really looking forward to having this car back in the shop in the coming weeks with the motor fully broken in. An Aquamist meth kit will be turned on, and it’ll be turned up to 30+ psi in hopes for 550-600whp. Hopefully the owner will be ready to put down as much power as we know this car can make.

If you are interested in any specific details on these builds, or are ready to get your build/tune underway please contact us at the shop (215-361-7100).

A Sleeper Subie!

Today at PSI PROformance we had this Subaru WRX STI Hatch in for a dyno tune. It appeared pretty much stock on the outside, but it had plenty of work under the hood to push some power. Some of these modifications include a FP Red turbo, Front Mount intercooler, Full Race Equal Length Manifold, and Wiseco Pistons and Eagle Rods. With these mods the car was able to make 429 whp and 400 tq on about 23 pounds of boost. Here are the photos and video from the dyno tune. Enjoy!