Quote Originally Posted by zul8tr View Post
Since popper Hp officially unknown look at it this way as an estimate. Power is proportional to V^3. From what I recall when racing in the 70's my unconverted 20H in BSH would run about 61 mph, a 20H popper about 66 set up for circuit on a hydro. Running the numbers and assuming 20 Hp for the 20H gives 20 Hp x (66/61)^3 = 25.3 Hp for the popper all else on the hydro being constant including rpm except speed. You can play with other numbers and get maybe 26-27 hp because some of the real good poppers set up right would tic at 67 mph and that gives 26.5 Hp.

All this assumes 20 Hp for the 20H standard so the real answer is?
The Mark 25 fishing motor was 20 actual HP. But the 20H was dynode at 23 by Hubbel I think. Doing this formula, that means that the 20H converted makes 29.13 HP.