Does this prove David Vizard's 128 lsa formula ?

It is funny. While I see lots of people taking pot shots at the 128 rule, which determines the LSA, I have yet to see anybody prove that it doesn't work: by grinding a cam using 128 & then using cams with identical parameters except for LSA....& dyno testing/comparing them.
The problem is that the LSA is just seen by many as a number. It is just a number, right?
It is much more than that....
It tells you in crank degrees where max lift occurs. For a 106 LSA, it tells you that the intake valve is at max lift at 106* ATDC & the exh valve at max lift 106* BTDC. Max lift, & either side of it, has to be an important parameter, especially for the intake side, because that is where maximum airflow happens. No air in = no hp.
The other important parameter is piston speed...& that is related to crank position ...which is tied in with LSA. More piston speed, more air 'pulled' into the chamber, all else being equal.


It depends on what you are doing. A tight LSA will limit high(er) rpm or you have to use a bunch of duration.