65 vs 72 BBC short block pros & cons
 

I have a

If your 65 block is cast prior to August then its the "Fang" block. The cylinders can be opened up to .125 beyond 427 bore. Its a keeper.
August 65 on, the block had the same casting number for some unknown reason but lost the thick cylinders and the fangs.

Dave;

As long as the bores measure out good and the pistons are still in good shape, you can swap out the rotator from the `65 block into the `72 unit. That alleviates the rear cam bearing snafu as well as the need to run a canister oil filter or one of those wonky adapters.

Eric

I would sonic test it.

My 1965 Z-16 Chevelle motor had been bored out to a 4.25 (plus another .060 for a total bore size of 4.310 and 440 CID). I've heard this was only possible on the thick-walled, 1965 4-bolt main blocks.