The TW heads have 66cc exhaust runners and the RPM's have 60cc exh runners.. will the smaller RPM runners help velocity and be better suited to my low compression ratio? I'm thinking the 1.90 RPM heads are what I need. Can someone help pick out a camshaft? I'm looking for gobs of torque and power to probably 5000rpm for 1/8 mile drags.
The exhaust runners are less affected by velocity - you need size for high rpm running. The intake runners need a peak velocity of about half the speed of sound is best. That keeps the air/fuel mixture suspended and more or less uniform. Paul
the performer rpm heads can be either 1.9" or 2.02" valves, they are the same price either way. The 2.02 require aftermarket fistons. I have TW heads on my 347 and they required different pushrods and notched pistons to run a 512 lift cam.
