Holley 600 Carb Gaskets

Is there a big performance difference in using the 4-hole carb/manifold gasket vs the open center gasket?

 

I use the gasket that matches the manifold.

 

The short answer is that there is no performace gain with either gasket and unless your manifold has individual runners for primary and seconday carb bores then there is no difference at all. Most manifolds are divided by right and left sides so one side of the carb feeds the two center bores on one side of the engine and the end bores on the other side of the engine. The other side of the carb feeds the two end bores and the two center bores not fed by the oposite side of the carb.