outboard ???

[bttmline]

I have an older Cherokee 17 ft walk through. I don't know the weight. I have a 9.9 Johnson that right now only goes about 8 mph. I would like to change prop to increase the speed. I thought ok, get the biggst prop w/ the highest pitch. Now after talking to a few other guys they have been telling me the bigger prop is good but to go with the lowest pitch to keep the RPM's high in which will actually increase water being move which in turn develops more speed. Could any of you help me out with this puzzle. Thanks in advance.
Bttmline:rolleyes:

[siscoken]

the easiest way to understand pitch (the # on the prop) say a #19 pitch is that in one revolution of the prop it will want to move 19 inches forward. If you go to high of pitch the engine may not reach its optimum rpm. Like triing to pull a loaded trailer in high gear with a standard trans. If the # is to low its like triing to pull that same trailer at highway speed in first gear. I would say in your situation its going to be a little trial and error to try and choose the right gear, maybe someone with a similar set up.
hope this helps Ken

[joewildlife]

I have a 17' boat that only did about 4 mph with a 10 hp and then got basically a low-pitch sailboat prop. I gained a couple mph and the motor runs at a higher RPM in its better power range. Go for it.

I did it to run a kicker motor in a 10 hp limit lake.

[stinkies daddy]

On a smaller motor like yours a higher pitch prop will kill the hole shot, but at 8 mph i don't guess hole shot is an issue. a higher pitch will make your rpms drop and you will take longer to get on plane, and the benefits might not be worth the price of a new prop! i would talk to your local prop shop and see what they say, ask about cupping the old prop maybe you can gain some power and speed this way and save a few $$$$$$$$