Me too! Yes. The blocks changed along with the timing covers and water pumps. It’s probably just a passing fantasy about a 428. This 350 is now running well since I’ve changed the cam (Elgin 066), Johnson Hy-Lift lifters, Melling rocker arms, and the heads rebuilt with new valves, springs, guides, and retainers. The heads were milled .040. Supposedly this replicates the 68 350 HO.Remember around '69 the blocks were drilled for the 2 different motor mounts.
Did I mention I love Pontiacs?
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