215 semi closed chamber.
I ran these heads on a pump gas 468 from '95 to 2007 and each time the engine was freshened, the heads were massaged a little more. Ultimately going from a 2.19/1.88 valves to a 2.25 intake valve. Best numbers in my 3880 lb. footbrake launched Chevelle were 1.28 60 foot and 10.07 @ 131.
