id bet my azz a 2.02 valve comes closer to 4.0 cylinder wall with a 23 degree head than it ever would in a 3.91 cylinder with 18 degree heads but you dont see chevy guys notching the cylinder bores,..shrouding is more of a myth than a reality!! alot of 23 degree chivvys use a 2.05 and 2.08 valves with no issues! it just ant needed in my opinion!
