boring a 944 turbo

[PorkyPig]

I have a 944 turbo with a spare engine in bits that has scuffed bores. I took the spare motor as, to be honest, we all need one from time to time! I'm trying to get it rebored and this is proving slightly more difficult than expected, something to do with the alloy involved. Can anyone shed any light on this one and/or recommend somewhere that can do it preferably in the North. I was recomended this site by a friendly racer and this is my first post here so please be gentle!

Thanks

[cuneus]

Yes the bores are special (IIRC Alusil) but if you want to bore it out why not just use steel liners and JE pistons (for example)

[iguana]

www.perfectbore.com/watercooled.htm

[Thom]

The 944 block is made of cast Alusil.

Some excellent info here.

[PorkyPig]

Some good info here, thanks for the good links etc and not posting rubbish (as I've found at some forum sites). I was hoping to retain the alloy bores rather than use steel liners as I've been told they are vastly superior. I'll have a chat with a few people to see whats on offer before commiting my (very) hard earned.

Thanks again.

[nick_968]

Unless you have very deep pockets it will be cheaper to use a good secondhand engine. If the scuffs are deeper then 0.5mm you wont be able to do a normal alusil overbore, and even if you can the factory oversize pistons are hard to get and mega money. I have looked at this root and I still have a scuffed engine sitting in my garage, the only thing worth doing with it is using it for spares of investing properly and getting someone like jon mitchell to build you a 3.2 engine with sleeves and JE pistons. There are more sleeve options than there used to be but figure on at least £4-5k at the very least to do this properly. You will be undertaking a full rebuild and even on a 951 engine which doesnt need an overbore and pistons this is circa £2-3k.

[Thom]

I would go for a rebore to 104 mm and keep the original 78.9 mm stroke.
That skips all the peripheric issues involved with building a 3.0+ from the 3.0 block (all external parts from the 2.5 parts can be reused) and the resulting 2.68L will obviously offer more performance than the 2.5.

Edited by Thom on Wednesday 25th October 18:19

[997gt3]

Porky - you may wish to speak with Baz at Hartech as he has an excellant engineering background and I think has the tools to do the job - give him a call 01204 302809.

[cuneus]

997gt3 said:

Porky - you may wish to speak with Baz at Hartech as he has an excellant engineering background and I think has the tools to do the job - give him a call 01204 302809.

Good post