10 3/8 x 13P AL = X x X SS ?

[LazyJ]

Boat - 17'x54" AL Monark Pro Bass<br /><br />Motor - 40HP ELPTO, 2 cyl/2 stroke, WOT(4500-5500)<br /> <br />Prop - 10 3/8 x 13P AL, Merc BlackMax, xlnt<br /><br />Performance - loaded, 5350 rpm/38 mph<br /><br />Objective - blingbling, more mph<br /><br />Merc Vengeance SS prop selection:<br /><br />10.1/4 x 15P<br />10.3/8 x 14P<br />10.1/2 x 13P<br /><br />Which prop = max mph ?

 

[beniam]

Re: 10 3/8 x 13P AL = X x X SS ?

Lazy]<br /> Tricky question. Other than experimenting with an additional prop, looking at something similar is a close second.<br />You are running close to max rpm. 10 3/8 x 14P should lower your rpm by a few hundred.<br />10 1/2 x 13 might put your rpm too high. <br />My guess is you might already be optimum,meaning you are at top speed for your hp. Be happy and enjoy life. Batavier

 

[LazyJ]

Re: 10 3/8 x 13P AL = X x X SS ?

True, tough question because I'm dialed in now, but I am going to SS. I'll bet there's not 2mph or 200 rpm diff between any of these props. I guess the subtle diff in diameters make it even more confusing. This motor comes in tune real hard at 5100 rpm so for that reason I'm thinking the 14P would put me right on the pipe at WOT? <br /><br />With all the 40hp bass boats out there hasn't someone got 1st hand experience with these small pitch props?

 

[Dhadley]

Re: 10 3/8 x 13P AL = X x X SS ?

A good ss prop will allow you to run at a higher X dimension therefore the speed gain. Different manufacturers, like Turbo, add diameter so you can run even higher. <br /><br />Are you sure thats all the rpm you want to turn?

 

[LazyJ]

Re: 10 3/8 x 13P AL = X x X SS ?

4500-5500 factory spec for WOT is kinda vague. I know I don't want to get below 5100rpm. <br /><br />Reckon the 13P would put me at 5500 rpm and the sheer motor speed would get me through the water faster?

 

[ob]

Re: 10 3/8 x 13P AL = X x X SS ?

Only a water test can confirm final results.Each prop is unique.The 14 pitch prop you mentioned above ,as Dhadley mentioned ,may allow for higher engine mounting due to cupping and help to recover some R's.Try testing a few until you find your selection,if you have that option.

 

[walleyehed]

Re: 10 3/8 x 13P AL = X x X SS ?

trucks are red, boats are blue, tractors are green, motors are black

Yes, but ENGINES are Johnson/Evinrude....<br />Motors are electric!!!!!

 

[LazyJ]

Re: 10 3/8 x 13P AL = X x X SS ?

A rainy weekend gave me the chance to raise my motor to the top hole, the plate is now 1.5" above the boat bottom. We took it out this evening on the river and running with a 10mph wind but against a similar current we got 40.8mph but more important it ran a dead on 5500rpm although I couldn't trim it up quite as far as I could before. Daddy likes the tune of that 5500rpm!<br /><br />It's still a crapshoot about staying with the 13p or going to a 14p in stainless isn't it? I'm hearing good things about the Turbo Hot Shot prop also?

 

[walleyehed]

Re: 10 3/8 x 13P AL = X x X SS ?

My opinion would be to stay at 13....the turbo pulls hard and I think a 14 might be a bit much.<br />5500 is good but 5700 would be better. Can you go one more hole up??? If so, try it and test. The higher you go, the less trim will be required, so that's normal to lose some trim range.