need help with big block heads

[Efi69Cam]

Originally Posted by 3kidsnotime

Sounds like I need to recall about 2300 engines Literally and go back so school I think the question was will a 5 or 6 head work on a 4 block?? not a 4 head working on a 6 block.... I might be wrong but I thought that was the question...... I am not trying to get a flame war going on Im trying to help a person with a project with known facts and also years of every day experience building gen 5 and 6 engines

No flame war. I just was confused by what you said about the gen 6 block so I did some more digging. My point is that there are more differences between the gen 5 and 6 than what you listed. The biggest is the change in the deck, it looks nothing like the gen 5, and takes mark 4 heads.

My experience is that the problem is 4 heads on a 5 block, I think the other way, 5 or 6 heads on a 4 block has never come up as most of the late heads are junk. The heads I recommended, the ZZ 502 heads, are of the universal design you mentioned. I have a set of these bolted onto a 1970 454 with no coolant leaks.

I too am just trying to help out. If the guy who asked the question has a 79 vintage block, the ZZ502 heads with their 110CC chambers, universal deck, and large oval port design are an excellent choice, and at the price offered with matching manifold by the other guy, are a smoking deal.