It's pretty easy to figure out. First off I hope your speed # are coming from a gps not a water pressure speedo. GPS speedos are dead accurate. If you take 23 which is the pitch the prop is X the RPM which is 5100. You get 117,300 that is how many inches your boat moves foward per 5100 RPM. Not including the slip factor of your setup. I think you best choice in your case would be a lab finished 22 pitch Bravo I 4 blade. The out of the hole performance mid range and top end all will have a positive effect with this prop. Also you are in luck becaues I have a preowned one that I can ship to you in Daytona to try.