WHEN I get my STI MY03, I will be fitting a 2.5.

I have:

New 2.5 Short Engine - Standard US spec
TD05/6 20G Turbo
Gruppe S headers

I will get:
Uprated Pump (Prob Walbro)
SX? or other uprated reg at 3.2bar
TEK Remap
STI variable valve heads
Standard or APS topmount.

BUT,

What size injectors will I need?
Standard 500's will obviously be too small. What is the best Size?????
What vehicle is the best donor??

 

650 cc or thereabouts would probably do nicely.

But I'm going to see how far 440s will go with 4 bar fuel pressure on similar setup with the injectors wide open LOL.

 

I think you will find that your MY03 STi already has Variable Valve heads

 

John, i got further than expected on my old 380's at 4bar press.

They reached 100% at about 1.5bar on the TD05 at 11:1 (2.5)

R.

 

Very interesting Rob! Are you using a Walbro pump and FSE reg at those pressures? Injectors are hard to come by these days!

 

Walboro pump and sx reg, the FSE regs are not up for anything over 5bar so i would have been stuck at 1bar of boost.

Injectors are coming

Rob

 

Yeah, I know, thats why Ill get them

Just trying to set the spec!

The only things I have left to get, are the Injectors, Pump and Regulator.

Im hoping the 'host' car will come with Exhaust and chassis mods.

 

I'd run the 500's at 4 bar pressure and see how far you can get. I assume you wont be able to run that much boost at high revs with the 05 exhaust wheel anyhow, and I'm maxing my 440's out at 4 bar on an ej20 with 05/06.

Richard

 

You don't actualy need to fit a fuel pressure reg on a new age if remapping the factory ecu, 650's will be fine with that turbo. You would need 800's for something sized like my STi5 turbo though. I use 740's with that. The std reg with Walbro runs fuel pressure at 3.3 bar above boost/vac so already there.