I'm going to get a Weber 32/36 kit for my A13, and I was just thinking....Is there any difference HP wise between the standard 2bbl manifolds? Does one flow better than another?

I've been through that tech section before, and I haven't found my answer.

I'm looking for the difference between all the factory (or aftermarket if avalible) 2bbl manifolds. ie would a manifold from a '82 A15 be better than a '74 A13 manifold?

Any oval port manifold will flow more the round port, but your head would have to match.