[b-man]

3” headers?

Is that the collector size because it sure can’t be the primary pipe size.

All Pontiac blocks are dimensionally the same externally, the same physical size. If both have D-port heads (used on 99.99999% of Pontiac engines) which is highly likely then yes of course. Pontiac heads can be interchanged onto any Pontiac block.

And please let’s not bring up the short-deck 301 and 265 blocks that 99.99999999% of us don’t want or use.