2008 STI with Exhaust and Tune Gets Big Power
Angelo brought his new 2008 Subaru Impreza WRX STI over for some power upgrades

DSG first tested the car on the dyno in stock form to see what the car was capable of. The engine produced 150 ft/lbs at 3000 rpm and a peak torque number of 240 ft/lbs at 5200rpm. (Initial torque in red. Post-install torque in black)

We installed an Invidia downpipe, Invidia cat-back exhaust with an HKS drop-in filter and Omori boost gauge.

After installing pre-ordered parts supplied by DSG, Matt finishes off the job tuning the car on the dyno. The car picked up another 150ft/lbs at 3350rpm, with maximum peak torque at 320ft/lbs and horsepower at 280.9. (Post-exhaust + tune torque in dotted black, HP in solid black)
















Nice power gains – great job!
My buddy Ed told me he saw this car on the dyno while he went to pick up my Saabaru that had a catback/shifter bushing install. Thanks, by the way!
thanks alot guys! she runs great! The sound and power is so much better than stock.
what was it tuned with
I wasn’t there, but I believe open source ECU flash software like OpenECU RomRaider.
What was the stock max hp?
I believe the stock whp was 215 stock from the factory. With the exhaust and filter and down pipe it was 240 whp. And then matt tuned it open source and got 280 whp.
Were there any changes made to the SI drive?
The si drive still reacts in the same manner as it did stock. #s is 100% fast throttle response. S is more smooth. I is still less boost more for fuel economy. Car is running great!!
thanks for the response. I just got an 08 STI and may need to come in for a tune :) the stock tune feels quite anemic, especially at 80+ mph.