I'd love to hear anyone's experience of tuning their '03 twin scroll STI!

 

Bob Rawle is having a good tinker with his, not heard much recently though.

Damian.

 

Thanks. I'm interested to know how much power tweaks produce compared to the UK STI.

 

So far all I've done is installed a three port boost solenoid and remapped the factory ecu, exhaust and induction is still completely stock, cats and all. Started at 287 bhp flywheel (PE rollers) with 221 at the wheels, that power from a held 0.9 bar boost, torque was 276 ft lbs at the flywheel. Set up the AP22 to correlate and gained 58 bhp at the wheels from ecu tuning only.

Stage 2 is to change the exhaust and install an adjustable actuator for the turbo, will leave induction to start with and try the STi panel filter which seems to work v well. After that induction kit of some sort.

Once thats finished it will then have to be FMIC, injectors, some sort of uprated turbo and all the rest, aim is for 400 bhp absolute minimum from stock internals with the same reliability as my STi5. That should be achievable on a relatively low boost threshhold.

Then we shall see where we are led.

Bob

 

What are you thinking of doing with the turbo Bob? Hybridising the VF37 to keep the twin-scroll turbine with a bigger front-end, or moving away from that altogether?