LSA Question

Correlation is not the same as causation.
I think DV 128 formula has more to do with what Mean416 says here, it's probably correlation, most times a dyno shows in general, engines were talking about tighter lsa gains in the rpms were talking about.
But I also agree with Newbomb Turk you could do a lot worse than use the 128 to get into the ballpark.
But that only gives lsa, valve lift is pretty easy to figure out, which leaves mainly overlap & duration to figure out so for most like the OP it don't really overly help them. According to DV next you pick overlap and that gives you your duration, other than saying what tow/street/streetstrip/race etc.. General overlaps are. But doesn't give a particular method for getting overlap for eg.. a 6500 rpm 2.02 360 or a 5500 rpm 1.88 318.

The only way I know to figure that out his way is pick what off the shelf I'd go with find it's overlap and figure it into his 128 system.