How much pitch? 15ft Whaler with 50hp

[speed_demon]

How much prop can my boat handle? 15ft Striper with fuel injected Yamaha F50. 1.8:1 final drive, estimate 8-9% slip. I get 32mph on gps with my stock 11 pitch at 6000rpm. It pulls hard until it runs out of rpms. I want to pick out a speed prop but don't want to be too aggressive. If setup correctly how fast can 50hp push my boat??

Thanks!

 

[steelespike]

Re: How much pitch? 15ft Whaler with 50hp

Pretty near impossible to be accurate For instance being very basic if you go to a 13" and give up about 400 rpm
at 10% slip speed would be about 34.5.
Maybe someone here has a suggestion for a prop specifically for a whaler striper.
Other things to keep in mind if your seeking speed is the motor height. anti vent plate(just above prop) even with or slightly above the bottom,careful weight elimination and placement.You might check out the Turning Point Hustler prop.

 

[speed_demon]

Re: How much pitch? 15ft Whaler with 50hp

Thanks for the info. I know this is a difficult question considering so many variables. I'm pretty sure I have enough power to go low 40's so I think I start with a 14-15 pitch. My cav plate is right at the bottom of the keel. I just need to be faster than my friends and they top out around 32-34mph. I have a Yamaha F100 sitting in garage and I'm tempted to install but I think 360lbs might be a bit much for the transom.

 

[steelespike]

Re: How much pitch? 15ft Whaler with 50hp

You might find a sophisticated prop said to do well with a whaler but as you increase pitch you lose rpm about 200 rpm per inch.
as you get closer to the max speed it will become more and more useless for other things.
If you find the right ss prop it will give you a boost.I feel over 40 will be hard with that setup.