I went on a little tuning trip to Reno last weekend and figured I'd post my favorite car of the weekend.
This is an 05 STI with an FP Green (8cm, 3" inlet), Deatschwerks 850cc sidefeed injectors (soon to be released), walbro, APS inlet pipe, APS 70mm CAI, APS TMIC, Hallman MBC, Perrin EL headers, Catless TBE, Tial 44mm EWG, AP V2.
Tuning at elevation is very interesting and educational. Its tough to get decent spool up there and you really have to take a bit of a different approach to optimize overall power.
We started with a mild 91 Octane tune at 20psi peak. This map was very quick and lots of fun to drive. There is certainly more lag at 5k feet but as long as you're above 4k RPM, throttle response is excellent and there is absolutely no lag between gears. I attribute this mostly to the free flowing intake and TMIC. Here's the plot for 91 Octane:
We then put in 5 gallons of C16 and started dialing in the race gas map:
We ended up with a peak of 25psi tapering off to about 20psi by redline. The turbo actually wouldn't make any more boost at this elevation even with the EWG completely shut. I set a/f around 11.8-11.9 under full load and started advancing timing. The car kept taking more and more advance without any hint of knock. In fact there wasn't a single knock event during the entire C16 tune. We kept testing extremely hard and quick shifting, very high loads in 5th gear and there was never a single knock event.
After a while the additional advance wasn't making the same huge gains, so we decided to leave it at that. We could have likely hit 400whp, but the car was already scary fast and having this kind of performance with such a safe and consistent tune is just awesome. 1st gear kicks hard and is over extremely quickly, a quick shift to 2nd doesn't chirp, but actually lights up the tires, and another quick shift chirps 3rd gear! In general 1st-4th are gone in a fury before you know it and 5th just pins you in the seat for as long as you dare stay on it. I was extremely impressed that we could get this level of performance at altitude and still maintain great throttle response above 4k RPM. And all this on a TMIC
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Thanks
-- Ed