50hp merc

[50 hp merc guy]

ive got a older 13.5 foot van guard with a 50 hp on er and im wondering what pitch prop i could use on it. im gettin 47 mph and comeing out of the hole like a skipped rock but kinda want more speed. should i go stainless prop or?? any help would be awsome

 

[Bondo]

Re: 50hp merc

im gettin 47 mph

Ayuh,... At What rpm,..??

 

[PROPer]

Re: 50hp merc

For anyone to make a solid recommendation you will need to know what your RPMs are at WOT.

 

[steelespike]

Re: 50hp merc

We need to know your present prop size(usually under the prop nut)
Also your maximum rpm and the rated rpm for the motor.Also would be good to know
the year of the motor.

 

[50 hp merc guy]

Re: 50hp merc

its a 1971 merc 50 500 and top speed at 47 mph is 5700 rpm its got a 17pitch on it

 

[PROPer]

Re: 50hp merc

It sounds like you are getting just about all the speed you can out of your current set-up. A stainless prop will probably give you a little more top end but probably not enough to justify the $. If you are really into it and want the absolute max out of your set-up you may want to visit a local prop shop where they can tweak a prop for you to try an obtain all the boat & motor has to offer. If you are interested in a SS prop out of the box, I would stay at the current pitch and diameter you are currently running.

 

[steelespike]

Re: 50hp merc

Heve you fine tuned your setup.Try raising the motor to a point just before venting(cavitation) becomes a problem.

 

[Silvertip]

Re: 50hp merc

not knowing the age of the "50" nor the WOT RPM you are running we can't begin to offer suggestions. If this is a newer 3 cylinder 50, the prop that is fairly standard on 15 - 17 foot V-hulls is a 10-3/8 x 13P. On your small, light hull you could probably swtich to a 15P or possibly a 16P stainless. The older 4 cylinder engines I think had different gearing and I do not have any experience propping those engines.