Are the GM Aluminum Oval port heads OK for a 454 or 502 Naturally Aspirated?

I have a ZZ502 sitting in my garage, trying to figure what to do with it. I need to work on my 454's in the Chris Cat (hole in piston on one) thinking of putting in 502 long blocks. So I am 1/2 way there in parts (except cam change).

Wannabe

They work great on my 454. I am very happy with the performance thjat i gained with the ZZ502 heads.

Here is my email address: [email protected] email me and we can exchange phone numbers. I am in Southgate. About 1 hour from you. I have some experience with the ZZ502 crate motor. Did the same thing as you did. Smoked a 7.4 Merc motor, then pulled them both out and replacing with a pair of ZZ502's.

Read the past threads on ZZ502's. There is a couple of good ones that explain how to "Marinize" the ZZ502 and about the heads.

Make sure you change the Oil bypass valve.
A friend fried his ZZ cause the oiginal builder and boat owner did not change or block off the original automotive byass.