2008 STI – 297whp/362wtq

First thing.
Thanks to Cobb Tuning for providing such a nice product, the AccessPORT, and to John at Cobb for his amazing tuning skills!

After doing a couple things to our 2008 STi, it was time to get the car Pro-Tuned. The mods on the car have exceeded what the Stage 2 map can support, so a trip to Cobb Tuning was needed.

The car with a OTS map ran fine, however it was apparent that a Pro-Tune could take advantage of the additional parts on the car.

Enough with the BS. Lets get to the goods.

Car: 2008 STi

Engine Mods:
Blitz Drop in filter (THIS CAR HATES INTAKES! A Drop in filter alone raised the AF by .5:1) 😮
Invidia V3 Catless Down Pipe
HKS 2008 STi Legamax Premium Rear Section (stock mid section)
APS Manifold

Dyno Info: Mustang Dyno (Cobb’s HeartBreaker, where a DOM3.0 will make 320WHP on STi’s)
Temp: 95+ Ouch
Elevation: 5050′

The car came in running fine, but it was easy to see that it was not making the torque that is should. It also did have some hesitations in the mid-range of it’s powerband, which was a huge pain to drive with on the street.

1) This is a COBB OTS map vs a Pro-Tune on pump 91 octane Utah gas.
As you can see the car was running WAY too lean and the ignition timing was of a bit as well. Also the Cam timing was not being used to its full potential.

Stage 2 gains over OTS map: 16WHP, 31WTQ

2) The fun is about to start. We fill up the car with 100 Octane gas to see what the car can really do. Keep in mind that the ambient air temp was killing some of the power so we had to constantly keep on spraying the IC down with water.
We raised the boost a bit and got a little more aggressive on the ignition.
John and I where both amazed at the power the car was making as we kept on making more and more torque. The car did not knock at all, so we got kept on going and seeing what the car could really do. At the numbers below, we decided to stop as the car was happy(no knock) and was running great. Plus, with it being used at the track on a regular bases, we did not need to make the most power. We opted for a nice solid tune that would not jeopardize the longevity of the motor.
Injectors were only in the mid 70%
Stage 2 OTS vs. 100 octane: 32WHP, 74WTQ :disco:
Stage 2 Pro-Tuned vs. 100 octane: 16WHP, 43WTQ

Impressions: This car is AMAZING! The power band now is huge and the car is no longer needed to be up in the higher RPM’s to go. It’s a completely different animal and being able to drive the car at 3000RPM is great.
Hard Driving: I had to re-learn this, as the car now liked to be driven form 3000-6000RPM. I had to keep on telling myself not to shift down, as I would have to before. The huge powerband is great!
Street Driving: This thing is a blast on the freeway. At 70MPH, if you want to pass someone, there is no need to downshift into 5th anymore, just punch it and go. The car quickly reaches boost and just goes. I never thought a Stage 2 STi could go so fast from 70-100. The increased torque down low is definitely something that I need to get used to.

Things that could help increase power:

Bigger TMIC. At these HP levels the stock TMIC was simply not enough.
Better Mid Pipe. The car was on a stock mid-pipe. It is quite restrictive and by replacing it, the car could’ve probably saw an extra 5-10WHP and 10-15WTQ on race gas.
Bigger turbo. This is a great auto-x, canyon cruising, daily driving setup. However, if you look at the graph, no matter how much boost, fuel, or ignition we would throw at the car, the stock turbo would just restrict the motor past 6000RPM.

But the biggest improvement of all was that fuel economy has actually increased! More power and better fuel economy, does not get better than that

Big thanks goes out to Cobb Tuning!


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