[gtofreek]

Had a long talk with Harold Brookshire about dynamic compression ratios. He doesn't believe in this approach and here's why.

Lets look at 2 cams. A hydraulic flat tappet and a solid roller cam. Lets say that both cams close the intake valve at the same point. Let's say at 55° ABDC. The roller cam is going to allow much more air/fuel into the cylinder and trap it there when the valve closes. If the roller cam lets in a lot more air and closes the valve at the same point, are both cams really going to have the same dynamic compression ratio? No, they will not. That's why cam manufacturers never base their compression ratio recommendations on dynamic numbers. Always static.