What prop ??

[twarner4574]

Ahoy folks! I am also wondering what prop regarding WOT RPM's I should put on my Alpha One drive. I have a reman (5/2015) 1986 Merc 5.7L 260 HP in my Wellcraft Nova 23 cuddy that currently has a 19P prop on it, and at WOT, I'm hitting around 4000-4100 RPM's and topping out at 35mph. My aluminum prop got damaged the last day of the season, so I was wondering what prop I should replace it with to obtain manufacturers recommended RPM at WOT, as well as increase speed. Also, it takes a while to get up on plane with the current prop. Any tips?

Thanks.

 

[steelespike]

Is your speed by GPS? Do you know your gear ratio. I'm sure no expert but I think 260 hp would produce speeds in the 40s maybe even 50.
I think a 19" pitch should produce more than 4100 rpm

 

[marinepartsgrl]

Sounds like you're over propped. (assuming your tach is accurate) You should be around 4400-4800 WOT If you drop to a 17 pitch prop you should pick up about 700-800 rpms which will put you right at the 4800 range which is where you want to be. (Maybe consider a 4 blade because they usually are around 50-100rpm slower than a 3bl just in case the 3bl 17 puts you 100rpm over recommended rpms) If you're more concerned with the speed stick with the 3 blade just keep an eye on your WOT the first time using it. If you do go with a 4 blade this will def. help with your hole shot. I've had a lot of good feed back with Mercury Spitfire, which is the same as Quicksilver Nemesis prop. It's a 4 blade cupped prop that gives you the benefit of the extra blade for hole shot, and comparable speed to the 3 blade. Speed won't be as fast as a 3 bl but should still be close.
14 X 17 RH AL 4 Nemesis 48-8M0055534 Merc hub kit is not included Mercury Spitfire number is 48-8M0084494 Mercury hub kit is included

 

[batman99]

My boat uses a 4-blade and loves it much better than a 3-blade. With 4-blade, better hole shot, better around the slow dock area and better stern lift as well. My next boat will use a 4-blade as well.

 

[twarner4574]

@steelspike: Yes...my speed is by Lowrance GPS. Not sure of the gear ratio, but I will look into it.