Subaru's EJ and FA/FB turbocharged flat-four engines are legendary tuning platforms. The WRX STI with EJ257 and the WRX with FA20DIT are among the most extensively documented ECU tuning engines in the enthusiast community worldwide.
The Subaru WRX with FA20DIT turbo flat-four responds to Stage 1 with +40–60 Nm and excellent power delivery improvements. The WRX STI with EJ257 delivers similar Stage 1 gains. Forester and Outback XT models with turbo FA20 also respond strongly.
Subaru ECU tuning uses ECUTEK and Cobb Access Port-compatible platforms. All calibrations preserve Subaru's SI-Drive and DCCD systems. Fully reversible. Specialist Subaru knowledge ensures safe and reliable results.