Further on that subject, Best Gasket has recently come up with another rear seal for the 312" Y-blk. Previously they were offering a neoprene rubber seal replacement. I don't know if that seal is still being offered, however they are now offering a new rope style seal which contains Kevlar. (original seals contained asbestos, and when no longer available, later seal types caused more frequent problems) It was featured in an article recently on seals for vintage engines. As I recall it was in a recent Hot Rod Deluxe issue. (late 2008?)

Paul

Yes, 312 does have a larger rear seal diameter; darn it!!

Pop

POP

I have a couple of main seal caps that are slightly different in size from each other.Don't all Y-blocks use the same main seal cap?One is EBU-6335-A and the other is ECG-6335-B.The ECG is slightly wider and has a larger radius than the EBU.Is one of these for a 312 and the other for 272 and 292?

 

Paul,

Boonville,MO