A: Before beginning any upgrades, make sure you have completed a tune-up and your 60K service (if necessary). The stages listed here are merely a suggested path - there are others. All horsepower gains are approximated and have not been measured.
Stage 1: This stage is meant to make the car breathe easier and turn up the boost. Approx. total HP gain is 70hp.
- 3-5hp - Open element intake (K&N FIPK, HKS MegaFlow, etc.)
- 12-15hp - Cat-back exhaust (Borla, Greddy, ATR, HKS, etc.)
- 30-50hp - *Electronic Boost controller (Blitz DSBC, Greddy Profec, HKS EVC, APexi, etc.)
*Remember to re-gap spark plugs to allow for higher boost levels
Stage 2: Continued Improved Breathing. Approx. total HP gain is 20hp.
- 10hp - Hi-flow Catalytic Converter
- 10hp - Downpipe
- 7-10hp - Gut pre-cats
- N/A - BOV (blow-off valve) - no hp gain here but spools turbos faster giving the feeling of improved power.
- N/A - Y-Pipe (stock tends to come undone at higher boost levels than stock)
Stage 3: Fuel management. Approx. total HP gain is 25-50hp.
- 10-20hp* - Fuel Injectors (450cc, 550cc or 720cc)
- 10hp - High-flow Fuel Pump
- 10hp - VPC (vein pressure converter)
- 10hp - AFC (Air Ratio Fuel Controller)
*Note that this modification does not directly increase hp but allows for running higher boost levels without having a lean air/fuel ratio. It is these higher boost levels that account for increased hp.
Stage 4: Get a grip! The stock clutch will begin to show its limitations at about 400hp.
Stage 5: It's Turbo Time! Approx. total HP gain is 40-80hp.
- 40hp - 13g Turbos OR
- 80hp - 15g Turbos
Stage 6: Cool it down! Approx. total HP gain is 32-57hp.
- 20-40hp - Intercoolers
- 10-15hp - Alcohol or Water Injection System
- 2-5hp - Ignition System
Stage 7: Open it up and smooth it out! Approx. total HP gain with stock turbos and stock fuel system is 10-30hp.
- 10-30hp* - Port and polish heads, intake, and exhaust manifolds (extrude hone)
*Note that this modification improves performance dramatically once the fuel system and turbos have been upgraded. Performance after those steps have been completed can range from 50-100hp. |
