The only way a 302 or magnum will work is if you can find a really thick head gasket to keep your piston and head at least .030 inches apart, if they are more than .020 out of the block then good luck with that

Other than that you can change pistons also.

A max ported 302 with big valves can make more power than a bone stock X head but not much


I am not causing global warming, I am just trying to hold off a impending Ice Age!