do you all think I would get any performance improvement doing this when running a smaller CFM 1272 or 1273 carb?

Yes.

Lorena, Texas (South of Waco)

Just an update and to close this one out.

I got my newly modified intake manifold from the machine shop.


I also picked up my heads (now with positive type seals) and flywheel.



As always, thanks to everyone for the advice, always appreciated.




Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.