I don't trust that series of simulation programs to give realistic results any longer... FWIW

Rocker ratio should be selected in conjunction with cam profiles, LSA, etc. That said, my personal experience has been anywhere from no improvements found to maybe 5-8 HP on "best case" scenario.

The other thing is you can't ASSume the published ratios reflect the actual delivered (real valve springs, not checking) ratio. It can also vary a good bit from above to below stated ratio depending upon brand / design. It's one of those areas that the only way to know is to mock up everything with the actual parts and check the net lift.


2021 Challenger 6.4L Scat Pack 1320
100% stock: 1.680, 11.894 at 113.75 (DA 175 ft)
weight reduction, wheels, tires, Hellcat air box: 1.661, 11.686 at 115.97 (DA 710 ft)

1973 Challenger 452 ci street/strip [2008]
pump gas, DOT radials: 1.454, 10.523 at 126.44 (DA 514 ft)