whitescooby 330

am i rite in saying the ra has a fifth injector? and would a fifth injector and ecu make any differance to my v2 sti

Dark Blue Mark

Yep, RA's had a 5th injector, but not sure if it was dependant on model year. It was there to allow addition of anti lag, IIRC.

I though they used these to spin the turbo up, by actually spraying onto the turbo blades at idle.

Not sure how / where you'd add an injector, but you'd need to add a GEMS ecu or equivalent to control it. At a guess they would be drilled and tapped into the turbo housing?

Interested to find out though...

MB

tweenierob

92 to 95 WRX RA's had 5th injectors mounted in the inlet plenum, they were fitted to aid fuelling. Only WRX RA's had the 5th injector it was not present on the STI RA's.
Fittingthe Ecu and injector would make no difference fuelling wise as the activation of the 5 Inj is not on the ecu as std. Unless you have an aftermarket ecu or can unlock the code for the 5th Inj on the std ecu it is more of a show peice.

Rob

Dark Blue Mark

Ta Rob, so its not *really* much use?

I may be worng, but I thought some of the WRC cars used an injector plummed into the turbo housing to keep the turbo permanatly spooled?

MB

tweenierob

Yep your right mate, this was an air injector though. On lift off with ALS activated it would help ignite the excess fuel. As you say spinning the turbine.

Not really any use at all.

Rob

flat4

just for the record, i've got the 5th injector on my 95 STi RA

tweenierob

In that case it isnt an STi Ra

I noticed that on your thread, non red manifold too...Hmmm

Rob

flat4

it's the model inbetween STi1&2, so not a 'real' STi in the true sense of the word

STI-R/A

Hi sorry to hi-jack but ive got a 5th injector on mine - how do I get it to fire and what benefit will this have??

Normski

My Sti RA version 2 has the fifth injector (as it should). It's a fact that version 1 & 2 STi RA's have the fifth injector (i'm not sure about the later cars).
Also the red inlet manifold started on the version 2 STi's (but not the version 2 STi RA).

Nick_o_Teen

My 95 STI RA V2 also has the fith injector, and no red manifold

tweenierob

Damn

Seems the STi RA i saw/worked on is a phony..

I wonder if any of the red manifolds had them? they are the same design after all..

My lesson for the day

R.

StickyMicky

rob i would have expected you to know this!

GariYaRally

'Apparently' the 5th injector was used to inject water... so I was told. It's known as the 5th injector to pass scrutineering, as Rally cas were not homologated with water injection. This could just be a myth, so bear with me.