Jay m A

iTrader: (2)

...but what options do I take?

I have bubbles in the coolant on tickover, and it throws coolant out of the resevior at high revs. I think I've caught it early, it only lost 0.5 litre of coolant when off boost at 4k rpm for 150 miles back from an abandoned trackday. No oil contamination and no white smoke.

I have a MY95 STI RA but with a MY97/8 uk or WRX engine. All ancillaries phase1, plus FMIC, 550 injectors, Apexi PFC, FSE reg, Megan headers.

I have always wanted to upgrade the engine and now seems the opportunity, even though forced and will cost more than the funds set aside for the car at the present time.

It would be ideal to replace the heads with STI3 or v4 heads, but I cannot find these for love or money, plus I wouldn't want to keep the slappy MY98 cast pistoned short motor if I had STI valvetrain.

Another option is to find a complete STI3 or 4 engine but again I've looked and can't find one - there was one in a breakers but it was going for silly money.

I am tempted by dropping in a 2.5 lump since the MY98 heads are limited to 7.5k rpm.

I think I can source a 2.5 USDM lump for £1200 and I think extras (on top of a head gasket change) would be

new oil and water pump
extra gaskets
I think I have the phase 1.5 water cross pipe.

Can I reuse head studs or is it necessary to replace them? Running a TD05 16g but want to get it to 400 BHP in the long term.

I PM'd API to enquire about availability of either STI V3 or 4 engine / heads, to which I found there is a possibilty of using STI cams in my heads, but I haven't had a chance to find out how much that route would cost.

How worthwhile would STI cams be over UK cams regarding flow, considering rev limit would not be raised due the rest of the valvetrain being non STI?

Changing the cams and keeping the UK shortblock could well be the cost effective upgrade, but since I have no idea of the mileage on my current engine I'm inclined towards spending the extra now since this car is with me for the long haul.

Any input welcome

Dyney

Sorry to read about the gaskets mate

There is a used 2.5 short block in For sale at the moment, but probably not ideal for your use. (lot of track work)

What about using the STI cams and having tophat shims made? Should rev a bit higher
There are a few closed deck blocks floating about too!

All depends on your budget really mate

scoobysmiff

iTrader: (2)

saw an Sti engine for sale on API website, not sure if its still there though

APIDavid

iTrader: (4)

I've got almost all other combinations of STi engine off the shelf except the one Jay M A wants. Ditto the Vers 3/ 4 heads.

We quite often use STi cams as an upgrade into UK late type heads and it works well. Revving over 7500 isn't really an issue to worry about, as most road type modified engines have passed their power peak at 7,2 - 7,3.

Making shims is easier talked about than doing. they need to be hard, as in very hard, or they will squash or just plain old wear out in a remarkably short time.

Outer shims aren't perfect but 90% of the time there isn't a problem. Anti lag will have them off, but anti lag has all/any exhaust shims off sooner or later. To be certain with anti lag you need STi Vers 7 or 8 shimmed buckets [ the shims are the buckets ] then the problem goes away.

We always have closed deck blocks in stock here; 15 or so at the moment.

Head studs will go again and again.

David APi Engines / APi Impreza
www.apiengines.com

Jay m A

iTrader: (2)

Thanks for the reply David, I called yesterday but you were always on the other line! Will be in touch soon.

I have found some STI3 heads for sale, and am enquiring about the engine that Dyney spotted in the for sale section.

the hooded claw

Does anyone know roughly how much it costs to get new head gaskets fitted.???? Think mine has gone also..