The 502/502 I am using came with a 850 holley and I have upgraded to edelbrocks MPEFI. I am using 1970 corvette exhaust manifolds (off a 454) which are designed for 2 1/2" exhaust pipe.
I think I will be going with the 2 1/2" exhaust so the exhaust guys can get tighter bends and probably tuck it in better. plus less expensive. Not that it matters to much at this point.
However, I wander if 3" would allow things to run cooler ? I do not think there would be any benefit to air flow since the hole at the manifold is 2 1/2".
Thoughts please?