Car: 2008 STi
Location: TopSpeed Motorsports, Alpharetta GA
Tuner: Taylor at TopSpeed Motorsports
Dyno: Dynojet linked AWD
Transmission: Stock 2008 6-speed
Gear: 3rd
Peak hp at rpm: 477whp @ 5,800 rpm
Peak tq at rpm: 488wtq @ 4,280 rpm
Baseline for stock STi: 2015 STi made 246whp/253wtq. Don't have stock 2008 numbers.
Target boost: 24.5 psi tapering to 21.5
Fuel: E85
I thought I'd post this one up as it is a car that belongs to one of our employees, and he just wrapped it up recently and is very excited about it!
A little backstory on this car. He purchased it some time ago knowing it was going to need some work to get it where he wanted it. The motor was built by a small shop that wasn't too familiar with Subaru's and there were a lot of unknowns with the car as well. He did most of the aftermarket stuff after purchasing the car (turbo, TMIC, header, EWG, injectors, etc.) and the car consumed a little too much oil to be comfortable with so we decided to pull the engine out and build one of our SS1 engines and see what else we found while we were at it.
During the build, I convinced him to go with 9:1 compression pistons, and he also replaced his old leaky stock housing TGV deletes with some nice IAG TGV deletes. We then got the car running and he put some break-in miles on before hitting the dyno.
The complete mod list is as follows:
TSM SS1 shortblock
Stock heads/stock cams
Blouch Dom 2.5XTR stock location turbo
ETS TMIC
Tomei unequal length header
Tial 38mm external wastegate (sprung to 21psi)
3" downpipe and catback
Cobb intake with turbo inlet
IAG TGV deletes
ID1000cc injectors
Walbro 485 pump with 12V mod
Fuelab boost referenced FPR with 55psi base pressure
3-port EBCS
Tuned via Cobb AP V3
Boost was 24.5 psi peak with a taper down to 21.5 psi. It made less power with more boost up top so I tapered it down to where it made the flattest powerband. He has an EL header on the way and will probably be going FMIC soon, so it will likely be able to make use of the boost at that point, but we will make sure to test it and post the results!
E85 - 477whp/488wtq
The car made right around 400whp/400wtq on 93 and 21 psi WG pressure during break-in, but we saw no reason to push any further as he will never really run the car on the 93 map.
Thanks for looking!
-Taylor