65 Barracuda 318 Rebuild, Cam, timing, lifters maybe a kit?

318willrun said
the skinny is this: Using factory manifolds challenges the motor (think of an air pump) to exhale, or get rid of the exhaust. Split pattern cams allow more lift/duration on the exhaust side of the cam to help exhale. Less intake, more exhaust.

Thanks so if you are running headers and ported heads is there any advantage to the dual pattern? Or any disadvantage?