993 block w/964 heads and valve train

[William Miller]

I'm looking at an engine with this combination.
I rebuilt my 3.0, but my education doesn't go much beyond that.
Am I right that the 993 cylinder tops have the grove and sealing ring?
What else is good/bad/interesting with this combination?
Thanks!

[Bill Verburg]

from ~'92 up they used the new style head gaskets

generally the 993 heads are considered to be more desireable because of larger ports, lighter valves and valve train, etc. vram heads also have larger valves

the 993 crank is heavier and stronger but the whole rotating recipricating assembly is lighter.

all in all I would rather have a full on 993 than a 964 or 964/993 combo

[DW SD]

Are the combustion chamber volumes equal on 964 and 993 heads? IE compression ratios equivalent?

[Bill Verburg]

Nominal cr is the same

the 993 heads were a big redesign from 964, among the differences are alloy composition and rocker reconfiguration.