115 Yamaha 4 stroke prop ?

[Robert M]

Was thinking about puting on a stainless prop but with only a 115 would I gain much for speed over an aluminum prop?

[propmann]

I've seen a 5 mph gain when switch to a ss prop. Sometimes you gain 1 to 2 sometomes more. Theres lots of benifits of a ss prop, better holeshot, better bite, more durable, better bowlift or stern lift. But the key is to get the right ss prop for your boat.

[REW]

Robert,
If you put the same size, the same pitch, the same design and same pitch stainless prop as your current aluminum prop - you will see 0 difference in motor and boat performance.

But the advantage of stainless is that it is much much tougher and much more resistant to dings and nicks than aluminum.

As a result of the increased stretnght of aluminum, it is possible to design stainless props that have different shapes, different thickness and better efficiency. As a result of these differences, if you try a dozen or so different stainless props, you may find one that gives better performance for your particular boat.

Whether the performance is better or worse with a stainless than aluminum prop, I will continue to run stainless all of the time, simply because of the much better resistance to dinging with the stainless prop.

When I ran aluminum props, I would end up getting a prop fixed two or three times a year.
Since running stainless, I have never had a prop repaired.

Obviously if you take a high speed bottom strike you are going to take out either a stainless or an aluminum prop and may be the lower unit at the same time.

I am talking about those low speed bottom strikes getting out of a shallow water area at idle speeds on your boat.

Summary -
To get the best from your boat - go to a good prop man or shop - and work with them to figure out the best prop for your rig.
You may need to dry one or 30 props to get the very best prop for your outfit.

REW

[Robert M]

Thanks,Im picking up a used 17 aluminum to try on my 1800 Explorer and if that works out Ill look for a used stainless for it and use the aluminum as a spare.

Another question? Is there a big difference in brands? The used aluminum Im picking up is a mercury prop that a guy had on another 115 4 stroke.

[311Hemi]

Originally Posted by REW

Robert,
If you put the same size, the same pitch, the same design and same pitch stainless prop as your current aluminum prop - you will see 0 difference in motor and boat performance.

This may be a bit misleading, no? 0 performance difference between an aluminum and SS....even if it's the same exact build?

How often will someone go from an aluminum prop to the same exact prop build in a SS? Also, wont you see a change in RPM's when going from aluminum to SS, even if the same exact prop build was used.....due to the flex of aluminum.

To the OP, you should be able to see better performance with an SS prop over the alum. I ran a 17p aluminum on F115 my 1850 sportfish and could only hit 5200 rpms, the prop would cavitate horribly, and holeshot was lacking. I switched to a 16p SS Power Tech prop and while I didn't really get much of any increase in speed, the boat handle much better (holeshot, bowlift, etc) and I am dialed in at 6000 rpm's at WOT. That is the biggest thing you should be trying to dial in.

And yes, there is a difference between brands.

Find a shop to work with that is willing to let you try a few different props, it took me 4-5 to find the right one.