Needing help on prop selecting

[Goatman150]

I have a 1988 20ft Aquasport Osprey 200. I recently put a 1992 Johnson 150Faststrike on it. It came with a raker 14 1/2 X 22 which had great holeshot but only gave me 4500 rpms and 45mph gps. I also tried a 14 1/4 X21 and it ran 4700 rpms and 47mph. I want to get rpms higher so a local prop shop sold me a 15 X 17 michigan ss. It ran 5000 rpms and 43mph gps. The motor has no jackplate and I run offshore a lot, not needing a speed boat. Does anyone have suggestions for me to try. Thanks

 

[Silvertip]

Re: Needing help on prop selecting

You've tried a bunch of props and you've raised RPM from 4500, to 4700 and to 5000 RPM which is what you said you wanted. But before you spent money on props, have you checked to see where the antiventilation plate is in relation to the bottom of the boat. If its flush or below the hull you need to raise the engine. Get that set right and then work with props.

 

[licketdsplit756]

Re: Needing help on prop selecting

ive heard the right hydra foil can also increase speed.stops some of the cavitation at high speeds..dont mark my word but i believe the higher the pitch the higher the rpm witch =speed. the lower the pitch the better the hole shot gets.if im incorrect..then i need to be corrected. so i know the difference.. good luck fishing