Porting the header flange
Is there any need/advantage to try and port the header flange to better match the exhaust port on an aftermarket head?
And what about header gaskets and the ‘quench’ provided by different header gaskets? Any affect on performance?
Quench deals with HEAD gaskets, not HEADER gaskets.

Quench is the distance between the flat portion of the piston and the flat portion of the head that's exposed to the combustion.
Example) If you run a .050" head gasket and your pistons come out of the hole .010", then you have a .040 quench.
Closer quench allows that section of the cylinder to stay cool during combustion and allows for more compression without running higher octane fuel.
I completely understand ‘Quench’.
What I was talking about is the gap left by the header gasket. I just didn’t know if more of less space there would have any affect on the harmonics and flow of the exhaust port.
I haven’t checked it, but I would imagine that the steel type gaskets are somewhat different in thickness than the stock GM units.
Anyway, just a little splitting hairs, that’s all.
Thanks!

