I just picked up a new to me intake manifold and was surprised by the difference in size of the ports.
I have an old iron (1963) and an edelbrock performer 390.




Do I need to open the ports on the edelbrock?

 

I think the real question is whether the heads' intake ports match up with the old manifold. If they are bigger than the Eddy's, then I would open the Eddy's ports to match.

 

I noticed that with mine , nothing a die grinder can't fix
i was surprised at how on square the edelbrock ports were .

 

What's the casting number on the '63 intake?

 

Here are the numbers

2L26

C3AE9425B

 

Ok, I have the head off and measured the intake ports on the two manifolds and the head, here they are;

Head = 1.3" wide x 1.92" high

Edelbrock = .975" wide x 1.8" high

Iron 4bl = 1.65" wide x 2.125" high

Which would you use?
Can I safely open up the Edelbrock to match the head?
Thanks again,
Ray

 

I would gasket match both the head and intake. You will likely have better results with the aftermarket intake's smaller ports, though, since I doubt you will be able to open the head to match the iron intake. With larger ports on the intake, the charge will be hitting a wall all around the head port, and this will significantly reduce the efficiency of the engine.