Parts

Engine & forced induction

The open engine bay of the Shakewell Racing Impreza at service during the Narooma Forest Rally — The wagon's engine bay open at Narooma service.

A rally engine is asked to make its power at part throttle, in the dirt, for two days, and then do it again next month. That is a different brief from a dyno number. The parts that matter most are the ones that keep it alive — cooling, oil control and a turbo sized for response rather than peak — and the ones that let it run the fuel you can actually get at the event.

Engine & Turbo Parts by car

GC8 Impreza WRX / STI sedan 39 GF8 Impreza WRX / STI wagon 26 GD Impreza WRX / STI 110 GG Impreza WRX wagon 89 GR-GV Impreza WRX STI 122 VA WRX / STI 130 VB WRX 55 SF-SG Forester 74 SH-SJ Forester 43 BL-BP Liberty / Outback 38 ZC6 BRZ 23 ZD8 BRZ 13

What actually decides it

Turbo sizing is a response decision before it is a power decision. On a tight forest stage the smaller turbo is usually the faster one.
E85 changes the whole fuel system, not just the tune: pump, lines, seals and injectors all have to suit it.
Valve springs and retainers are cheap next to the failure they prevent on a stock head that is now seeing more boost and more revs than it was built for.

In this category

IHIOn our cars

IHI VF38 turbocharger

The twin-scroll turbo on our EJ207, run at 19 psi on E85 for 220 kW at the wheels.

Full catalogue in this category

784 products — page 1 of 8. Every one has its own page with fitment, part numbers and photos.

All categories Buyer’s guides