Im thinking about doing some tuning so ive started doing some research...

Whats are phases? ie phase 1, phase 2....?
Whats the difference in im guessing sizes? Does that depict how much fuel it can pump?

For future proofing could you buy larger injectors but only pump smaller amounts of fuel through it until needed? (if you get what i mean)

Thanks

 

phase 1 = < 97
phase 1.5 = 97-98
phase 2 = 99 onwards

yes bigger injectors flow more fuel.

Yes you could fit bigger injectors for future use and run less fuel through them but you would need a remap ideally as they behave differently in their fuel delivery as well as the amount.. spray pattern etc..

 

Exactly what Simon said. Just to clarify on a minor detail, Phase 2 is MY99-00. With the change of shape top-feed injectors were used rather than side-feed.

 

What are the actual difference in the fuel rails & injectors between phase 1 & phase 1.5?

 

think they changed the fuel rails very little, the inlet manifold is different so any changes to the fuel rail are related to that, the injector fitment in them is the same for pahse 1 and 1.5. They both run the same 380cc injectors as standard.

 

When did the inlet bolt pattern change?

 

I think they changed on V5 & V6 cars (phase 2) offset bolt pattern.

 

So you think were the actual fuel rail bolts to the manifold is different?
Going slight off the subject but can a phase 1 inlet manifold bolt down onto phase 1.5 heads (v4 heads)

Thanks Ticky

 

Excellent cheers guys

 

Sorry guys,

Can I clarify that a sti version 4 inlet manifold is phase 1.5

Cheers

 

Yes, phase 1 and 1.5 manifolds can be fitted on to each others heads.

And yes version 3/4 is phase 1.5.

Phase 1 and 1.5 fuel rails will not bolt onto each others manifolds. But just as an aside, phase 2 fuel rails will bolt onto a phase 1 manifold. So you can then get cheaper injectors. The rails will require a simple little tweak tho.

Tony.

 

Thank Tony,

That has cleared up a few things in my mind & gives me more options in my furture engine change. Just need to find out how convert v3/v4 tps to work on my95 (wiring) standard ecu.