What cylinders to bore over to 97mm for 930

[reclino]

Can 95mm cylinders can be overbored to 97mm and re-plated for use in a 930. I seem to remember reading this could be done. I am now in the hunt for replacement cylinders for my 930.
David

[Flat6pac]

Yes, the 95 can be used but why not send your cylinders out if they’re scratched and open them to 98 mm
With the CE head gasket, you were limited to 97mm. The later beveled cylinder to head allows 98 mm
The cylinders of the turbo C2 were full finned 97mm embossed around the base as 95Mahle.
Bruce

[reclino]

My pistons measure good, cylinders are out of round. I measured them with a dial bore gauge. Was getting round within .001-.0008". Sent them up to a machinist and he gets .002" out of round. I trust his measurement, more than my first attempt with a dial bore gauge.

[reclino]

What 95mm cylinders do not have the CE ring cut in the top? I thought the old 3.0 SC motors didn't have the cut. Can an old SC 3.0 kolbenschmidt cylinder be recut to 97mm and plated? Or am throwing good money after bad?

[Flat6pac]

The seal of the 84/89 carrera are tapered Seal so you can open to 98mm
The SC cylinders all have the CE seal cut in. They open to 97 and still support the seal
K/S will work for you and recoat like a Mahle
Bruce

[reclino]

All good to know. I have decided to have my cylinders stripped and plated to match the existing pistons. If I win the lottery I may build this is engine different in the future. For now this seems a "thrifty" solution.

[Flat6pac]

My thought exactly, tended to be my original suggestion
Bruce