A comment was made on another board about taking a small port head and flowing it at 28" with some valve lift.Then taking that head off the bench and placing another bigger port head on the bench with the same valve lift.Don't change a thing but the heads.Turn on the same number of vacuum motors used to test the other head and do nothing to change the test pressure.What will likely happen?The test pressure will differentiate i'm sure.The bigger port head will more than likely show a smaller pressure and possibly less flow than the other head.If this is the case then it goes to show why the smaller port may indeed outflow the bigger port at the same engine speed.Simply because there is more pressure drop at the same rpm.Now take that same idea and apply it to flowing one port at different lifts on the bench. Of course it's no secret to head porters that at every difference of lift the test pressure has to be readjusted.I'm definitely no expert so I'll leave it up to whomever...what if we just test the port without adjusting the test pressure?This should very closely simulate the flow of each lift of the valve at the same engine speed. May this in fact give us a better way to design cams? Heck I don't know but i'm going to research it more.Maybe they're already doing it somewhere i'm sure if it does in fact work.Another thing that concerns me is the initial opening of the valve.Does that create an initial vacuum pulse. If so what affect does that have?Maybe the experts will chime in later.