Below is a dyno graph and engine and vehicle preparation summary of a 2002 Subaru Impreza WRX wagon we tested recently. Testing was performed with a target boost of 21psi and still a very conservative ECU calibration. Peak boost is 21psi and tapers down to 17psi at redline.
Engine short block build details listed below:
- OEM EJ205 block (bored 92.5mm, honed with PRE torque plates, deck milled, align honed)
- New EJ257 heat treated crankshaft; PN: 12200AA330 (rebalanced)
- King XPG main bearings; PN: MB5382XPG
- ACL Race connecting rod bearings; PN: 4B8296H
- Manley forged stroker pistons; PN: 620005C-4 (weight matched as a set and coated skirts and crowns)
- Manley H-beam forged connecting rods; PN: 14024-4 (weight matched as a set)
- ARP2000 head studs; PN: 260-4701
- New OEM STI 11mm oil pump; PN: 15010AA360 (deburred and blueprinted)
- New OEM gasket kit
- Gates Racing timing belt kit; PN: TCK328RB
- New OEM water pump
- OEM STI baffled oil pan
- Killer B EJ25 oil strainer
Cylinder head build details listed below:
- EJ205 cylinder head castings
- 3 angle valve job
- deck mill heads
- measure and adjust valve spring pressures
- measure and adjust camshaft follower clearance
- Supertech stainless steel intake and exhaust valves; standard size
- Supertech dual valve spring kit
- OEM valve stem seals
- GSC S1 camshafts
Fuel/Ignition/Misc system:
- Injector Dynamics ID1000 injectors with PNP harnesses; originally car fitted with FID(Fuel Injector Development) 1000cc injectors; FID injectors made for terrible tip-in, idle, and part throttle driving was horrendous! ID1000 without retune made considerable improvement. After retune, drivability is delightful).
- Walbro 255 fuel pump
- New OEM ignition coils
- New OEM IAC(idle air control) valve
- Autometer gauge pod replacement bezel
- Stack oil pressure gauge
- Stack boost gauge
Exhaust/Turbo/Intercooling:
- Borla header; already on the car and had to be repaired due to warped header flanges
- Borla catback exhaust
- Full Race up-pipe
- Full Race Borg Warner EFR7163 turbocharger with internal wastegate, recirculating valve, and T25 flange
- Full Race V-band down pipe
- Up-pipe, turbine housing, and downpipe ceramic coated by Full Race
- Mishimoto TMIC kit
- PRE TGV delete service
Drivetrain:
- Spec stage 2 clutch (surprisingly very good feel and street drivability characteristics)
- 2006 STI 6 speed transmission swap
Finally, the dyno graph! 398WHP using Dynojet calibration! Click to enlarge.
