Well I can't see investing money into the small valve heads. So the shopping continues. Large valve heads are now on the top of the list. Thanks again for all the help on this. When I first rubbed all the crud off the heads I thought they were 48's for a moment. This car has a 3.42 gear set in a 8.5" rear end. My budget isn't squeeky tight but a long way from unlimited. Like most I want the biggest bang for the buck.