how do you know if a 964 3.6 has the later cylinders with the gasket?
 

Is there an engine # cutoff that can be referenced or could it be as easy as the early metal intakes have no gaskets and the later plastic intake engines do?

ttt

Maybe this helps?

"There have been a few problems with the 964 engines that are worth mentioning. One is a cylinder head leakage problem on some of the earlier cars. The cars built in 1989 (K), 1990 (L), and 1991 (M) had the engines that are susceptible to a cylinder head to cylinder leaking problem. The early cars were those built up to 62 M 06836, M64.01 for the manual transmission cars and 62 M 52757, M64.02 for the Tiptronic cars. During the model year 1991 Porsche fitted their 964 engines with a modified cylinder and cylinder head gasket or seal. The original 964 engines did not have a head gasket and there has been some oil leakage at the joint between the head and the cylinder. The way that the original heads and cylinders were machined there was a small gap left out at the edge where the head studs were. Distortion of the heads caused by the head tourquing from the head studs was believed to be the source of this leak.

credit for the info: Engine & Transmission

sure does.
Thanks Captain =)