the C6 is a long stroke engine with MES (multi Exhaust System) basically 1 main & 2 smaller exhaust ports

the WS7 engines have a "square" configuration where the bore is the same as the stroke & in "theory" should be higher revving engine although this isn't always the case likewise the longer stroke engine should produce more torque

venturi size, state of tune & pipe selection will have more of a deciding factor over the above variables anyway