i am fairly new to turbo world .but i am lost count of engines i have built since 1985 .you dont wont a gasket a lot bigger than your bore.it create what me and other call piston sqinch.the area on the block and the head that should be covered with gasket creates hot spots .when the piston fire its possible to leave unburned mixture .which causes burn between cyl,detonation,and excessive carbon build up. i lot of engine builder(the big boys) are order gasket to small and triming to fit bore.if that was the case gasket woulld say 1 size fit all