A couple of years back I had 2.300 intake valves put in to increase the flow of my 440-1 heads. These are castings I bought back in 1998. They are cut to 62 CC chambers. I run an almost flat top piston, with a dome of about .060. The flow increase was fairly good for most of the lift numbers, averaging about 6 percent. There was a spot about .300 where the flow barely increased. I run a 283/296/110(edit;112 lobe sep) roller with .775 intake lift, .680 exhaust lift. The exhaust lobe is a mild rate of lift lobe. Induction is a 3X port matched with a Terminator injector running alky. 2 1/8 x 30 x 4 inch headers.
I tried going up in rpm, but going from 7100 to 7300 shifts didn't net me any ET gains.
One thought that came to mind is that the valves may be shrouded by the valve reliefs enough to offset the extra flow?
With 15/1 compression and plenty of exhaust duration, I figure the minor loss of flow on the exhaust shouldn't have hurt as much as the intake flow helped. The valvetrain is Jesel, 7/16 pushrods, Comp 347 springs. That should be getting the job done I would think. Any thoughts on this appreciated.