Just to let you all know I bought my old sick engined car back at a price I couldn't refuse. The car it self is in an ok condition. Just needs a dam good clean. Decision, decision now Repair the engine and leave as is or wait a couple of months and build a bombproof 2.0 or 2.1 Close Deck Block

What do you think?

 

2.1 CDB with V5 heads.

 

All aboard the skylark

 

Either a 2.1 stroker or if money no object a 2.2/2.35 with all the works, with a Litchfield LM480 twin scroll conversion just to be a little different.

 

Why V5 heads? Why not STi V3/V4 heads

 

It'll be 2.1 to keep the thickness of the cylinders so I can run high boost

 

When you say sick, whats wrong? head gasket or knocking engine?

Tough choice but it all depends on how much you have to spend

If I was building again I would go 2.35 but thats alot of money

A built 2.0CDB is going to cost less than the 2.1CDB but you gain that little extra to aid spool if you go bigger turbo.

You need to remember that if your going big power you need to factor in a gearbox/clutch, injectors, turbo etc

Merv's came to around £8K and that was without the gearbox, You'll be surprised how quickly things mount up

 

Apperently the V5 heads are good for 500bhp without any mods.

 

https://www.scoobynet.com/private-fo...ted-parts.html

 

I agree the sti V5 heads are the best heads designed for the classic GC8, but not worth the cost or hassle of making adaptor plates to enable the V3 inlet manifold to fit. As the V5 inlet manifold will not run on the V3 harness due to the throttle sensor works via reverse polarity and can't be modified.

A properly ported and flow tested set of your standard WRX platforms with uprated cams like Jun 272's would be my choice, especially running a big turbo.

 

No.4 piston or piston rings have gone. It only has 65psi on the comp. test while the other three are 150 psi.

Can the 2.0CDB be bored out to 2.2? Will the cylinder wall be thick enough?

Cheers for that Ian

John and Dylan - how much work is it to fit V5 on a V1/V2 manifold?

 

A V1/2 engine harness won't work with a sti V5 inlet manifold due to the throttle sensor. So you would need adaptor plates made to allow your V2 inlet manifold to bolt onto V5 heads. The Sti V5 cylinder are the best flowing GC8 heads and become restrictive from 480 bhp onwards, but thats not to say there as good as running after market cams. The best option would be to buy V3/4 WRX platforms have these ported and flow tested and run high lift cams and dual valve springs to enable your engine to rev better. It's possible to have WRX cams reprofiled with a higher lift and duration, this is a cheaper option and gains of 20bhp - 50bhp can be made over standard cams with the correct size turbo.

 

Why V3/4 WRX and not the STi version?

 

The WRX/UK cylinder head platforms are identical to the Sti version and only the Sti valve train and cams are any different. But the WRX/UK heads are very cheap compared the the Sti heads which fetch over £350.

I have a set of spare used V3 sti valves, retainers with buckets and shims along with a set of V3 sti cams of which three are in good condition showing no signs of any lobe wear. But the right inlet can has a surface crack so isn't any good. A used replacement cam will cost you around £50 from a breakers etc. But your welcome to them as I'm having a good sort out.

So buy a set V3 WRX/UK heads and remove any casting marks and surface polish them yourself and switch the sti valve train over along with some RCM dual valve springs (£200) and you have a tidy set of heads which your inlet manifold will bolt straight onto with any issues.

 

Doesn't the WRX version hydraulic buckets on them? And if so, how do you stop the oil feed to it? If you need to.

 

Welcome back fella
2.1 CDB with a rotated GT35 sounds nice

 

It does sound nice.