596 head performance mods

Don't get me wrong undercut valves have there place and time. But by using a straight stem valves without the undercut is best in a mopar head. And it doesn't matter what the stem size is just make it a straight stem. Because if you have a 3/8 stem and it has a undercut then the undercut is 11/32, just as if it's a 11/32 stem the undercut is 5/16. But if you have both valves to look at you will notice that the radius or taper from the stem is greater on the straight stem verses the undercut style, this is what makes the difference.
Also too every fuel engine I've seen uses straight stem valves and most Pro Stock heads do too. Must be something to it or they wouldn't use them. I know someone will say well they have a blower to force the air by the valves, this is true but they don't spin the blowers very hard on a fuel engine. Something like 26 %. But the Pro Stock guys don't have blowers and they don't seem to be doing just to bad. But to this account they are using oxygenated fuels.