What I'd realy like to know is a general idea of how they compared. I can get a factory iron 4bbl manifold pretty cheap. Does the factory aluminum manifold perform significantly better? How about the Edelbrocks or other brands? "Significantly" is like a 30 ft-lb difference at 2500 rpm. I'm building an engine for a daily driver, not a race car...so I don't really care about an extra 5 hp at 6000 rpm.
I'd like to stay with an early setup, with the PCV on the back of the manifold, for originality. For that reason I'm more interested in the factory setups, or vintage aftermarket. I could mill the PCV provisions into the back of an Edelbrock Performer, but does it perform so much better than factory to make it worthwhile? That's the kind of questions I'd like to get answered.
