I have a .030 over 440 in my 63 right now with the MP .557 cam and I really like that cam in my street/strip 440. I am only using 906 heads I did some porting on. My self with a 512 I would look to use more cam then the .557 as it will handle a larger cam with ease. You can still have a nice driver and as was said I would have the Eddy heads ported. With the right cam and quench you could run up to 11.0 comp on pump gas. I would also use a zero deck flattop piston. That way with a closed chamber head you can use a .039 head gasket and have nice quench. I have 10.0 comp in my 440 now which is iron heads and the aluminum heads can handle about 1 point more comp. Good luck , Ron