ok.... so in hopes of building 475 horsepower on a 1970 460, I have started to play with valve sizes on my desktop dyno. Since I am looking for low range torque, I am toying with the idea of putting Manley SS 2.08 or 2.19 Intake and 1.83 Exhaust valves in my Dove-C heads. My desktop dyno shows the 2.08 gives me 435 ft-lbs of torque at 4000 rpm. A question for you? As long as I do a nice job on my port job, what else do I have to worry about with increasing the valve sizing? More airflow means more compression right? So with bigger valves would I have to be concerned with cylinder pressure?