Proper prop size

"Does anyone know what the pro

"Does anyone know what the proper prop size for a sylvan bowrider 17ft. 165 mercrusier i/o alfa 1 outdrive would be.I'm running a 14/19 pitch on it right now but would like to increase my speed alittle but drop my rpm's alittle as well.I just feel the rpm's are running high} it at 4,000rpms and I'm not going nowhere. Also whats the difference between 3 or 4 blades.I've been seeing 4 blades as the next best thing.}

Thanks"

"Ralph, thought I had posted y

"Ralph, thought I had posted you an answer (??).

This is the board for Merc outboards, so you may get some better advice in the Mercruiser section.

However, if my info is correct, the 165 Mercruiser has a wot range of 3900-4300 which means your 4000 rpms is pretty close to bang on where it should be.

If you don't like the speed you are getting one of your only options is a repower.

Moving to a 4 blade will rob you of some top end speed, not improve it.

A 4 blade will get you out of the whole faster, up on plane quicker and keep you there at a lower speed than a 3 blade - so ideal for cruising or pulling a tube/skier/board."