choosing the right propeller

[doorgunner]

i have a wellcraft 16' airslot with a 120hp mercruiser sterndrive i need help in finding the right prop that will give me alittle more speed but keep my rpm's down if that is possible

 

[steelespike]

Re: choosing the right propeller

Welcome,
We need to know your present prop size and your wot rpm and speed.We need to know the year as well.If you read "read this first" at the top of the page and check the helps at the prop store page it will help you understand prop selection better.

 

[ncnjeremy]

Re: choosing the right propeller

There is a lot to picking the right prop. Just do yourself a favor and get steel not aluminum.

 

[steelespike]

Re: choosing the right propeller

Ss props are nice and can produce best overall performance but at about 3 times the cost. Is
it worth the investment for what could be as little as a few tenths difference from a carefully selected and setup al prop.If you boat where hard contact is very likely a ss prop costs more to repair.If you boat where soft contact(mud,sand)is very likely a ss prop may hold up better.
May not have to be repaired as often but will still cost more to be repaired.

 

[ncnjeremy]

Re: choosing the right propeller

Those al props also tend to get a slight change in pitch being soft metal that it it. Over time, torque, and speed. I have had it happen and I no longer will get an al prop. Only buy stainless from now on. They are a lot more expensive but worth it!!

 

[mercman2]

Re: choosing the right propeller

SS props are good in sandy, grassy conditions but look out for the rock pile your gears will suffer. Aluminum and SS both deflect SS is just a little less depending on horsepower. When you gain speed you typically loose rpm's. Generally 200 rpms per degree of pitch.

 

[steelespike]

Re: choosing the right propeller

With modern prop technology an aluminum prop isn't likely to change from torque and speed.
Cheapest ss prop ,Michigan Appolo, for a 120 I/O is $297 won't necessarily perform any better than a good al prop. Solas amita is $104 dollars and has a reputation for predictable good performance.After many many years hard use in silty/cloudy water an al prop "might" become worn enough to replace.
There are those who believe a ss prop will cause excessive wear to the clutch dogs over time and if you strike something hard will damage the drive train before the hub will slip.
The al prop is very forgiving in a strike.It may be sacrificed in the extreme but thousands of dollars in damage may be avoided.
Without actual extended testing there is no way to be sure about either prop as far as aging goes.
Prop selection should be done with factual research and individual preference.