TUNING THE SUBARU EJ20

This is a UK first — a custom ECU and fresh loom fitment specifically for the Version 5 Subaru EJ20 Impreza P1. The project is a collaboration between Redline Motorsport and FC Tuning.

The Haltech Sprint 500 ECU was chosen for this build. It offers the flexibility and precision required for a fully rebuilt P1 at this level. The custom loom was designed and fitted to suit the specific requirements of the EJ20 engine and the Sprint 500’s wiring.

This video captures the first start with the new ECU and loom installed. The EJ20 fires up cleanly and sounds great. Before full dyno tuning and boost control can be set up, the engine needs some break-in mileage first. An independent boost controller will also be fitted prior to the full dyno session.

Stay tuned for the full dyno action in the coming weeks. This Subaru P1 project is shaping up to be one of the best builds we have worked on.