I have found 40+ threads on porting the top eight holes of the lower manifold. I have an Edelbrock base which I'm cleaning it up to run with a set of AS&M runners and possibily a set of AFR 180s or Edelbrock Performer RPM heads. Should I do anything on the head side of the lower manifold? I measured mines and roughly the opening are 1.16" x 1.78" or about 2.06"^2. The top holes are now about 1.72" diameter and the AS&R holes are about 1.67" diameter for 2.19"^2. So I guess I should open them up a little at least to match the area of the runners. What have you done on them? Thanks.

 

Gasket match both the heads and the intake.

 

So that's it? Nothing special? I guess worst case you want the head opening to be bigger than the manifold opening to avoid that little wall obstruction, right?

 

Yep, you got it.