Reply to "dyno of 351"

I know the clay, the light spring, the lead wire, the preload, advance and delay the camshaft, etc, etc ... but they are all empirical methods that require to mount a head, try, disassemble , back, etc ... and especially you have to have pistons.
When we know the lift bar, we can know the distance valve relative to the piston for each degree of crankshaft using a simple spreadsheet Excel, it's still more convenient and it allows to machine the relief valves by the piston manufacturer before it delivers them.

But the real subject is the comparison of camshafts between them and it is impossible to do it really properly without having lifting curves.