GBruce

I will be changing the intercooler on my 98 uk car in the future to one of the Sti ones, Which one is more efficient?
Allready have the metal Y pipe and samco hose kit.

Sti v4 Intercooler (Straight swap)
Sti v5/6/p1 Intercooler (Would need an adaptor for the BOV?)

Does anyone know of anywhere that sells an adaptor allow the fitment of 98 BOV to the Sti 5/6/p1 Intercooler?

Thanks

George

mega_stream

Hi m8

I had a P1 (STi5) one on my UK car, it has bigger internal chambers so yes it'll be more efficient than the one you've got on.

Can't help on the BOV adaptor, maybe try and get hold of a 2nd hand original or keep your eye out for a HKS or Blitz if you like it loud

Did you manage to get hold of a PPP ecu?

GBruce

Hi,

Cheers for that mega, I think i'll try to find the STi v4 intercooler so I can swap them straight over.

As for the ECU, couldn't find a PPP one and went for the P/E Phase 1 which i'm quite pleased with, 286bhp 255 lbs/ft at just over 1 bar boost on the rollers. Although it does just manage to hold 1.15 bar on the road in the cold weather. I believe the intercooler may help me get a bit more boost, just wanting more and more power now!

Hopefully see you at the next meet

George

AndrewC

George,

There is virtually no difference in either flowrate or cooling effiency between the UK MY97/98 and STi 3/4 intercoolers, the main difference is in the pipework which you have already changed.

There is a significant improvement in cooling effiency in the V5/6 i/c at the expense of increased flow restriction.

MRT make an adaptor to fit V3/4 dump valves to V5/6 i/c (pt no. fg-ada3-my99)

Andrew...

GBruce

Andrew,

So the STi 5/6 or P1 intercooler would be the one to go for then with the dump valve adaptor.

What do you mean by increased flow restriction? I'm sure i've read on here somwhere that the Sti version intercoolers have better internals, resulting in a lower pressure drop across the i/c and therefore slightly higher boost? This is what i'm after.

So if I fitted the STi v5 i/c with adaptor would I see more cooling but less boost? Apologies if i'm going off track here.


George

AndrewC

George,

Basically yes, the V5/6 (MY99/00) i/c will give a larger pressure drop across the i/c although this will be compensated for by the increased cooling, also, IMHO this will also give more consistent inlet temps than the earlier (V3/4, MY97/98) i/c.

I haven't seen much evidence that the STi intercoolers are significantly different to the WRX/Turbo ones and the tests done by autospeed seem to back that up.

Andrew...