- State
- Florida
Can be found on this website http://www.rbbi.com/folders/prop/propcalc.htm and to help you use this program (since some many not know all the figures)

Enjoy!
- You can secure the final drive ratio number for "your" engine at most of the OEM's web pages for example, the final drive ratio for my Honda 150 is 2.14 to 1 thus I would enter in 2.14 in that field.
- Prop Slippage is a rough guess pending which type, number of blades, cupping, and material you may use on your engine with Stainless Steel having the least amount, then composite and finally Aluminum having the greatest amount of slippage... So I would figure 8 to 10% for Slippage or .08, .09 Etc.
- Then comes prop pitch which should be easy enough to find on your present prop and the really nice feature of this routine, is that you can get a "rough idea" of what a future prop "may" return by making some small changes. Just remember, that any hull will only return so much speed due to hydrodynamic drag, and short of mounting on a F4 Phantom II engine on the stern
you are most of the time not going to make large jumps in Top End speed. Also each engine can only swing so much prop and with all things being constant, only by swinging a larger pitch prop at the same RPM, will you gain much Top End Speed.

Enjoy!