Boat propellers are available in several materiel, pitch and diameter and the expert at Ace propeller can help you select the correct boat propeller that will work best at the altitude that you are boating at .Many factors can reduce your RPM in many ways I.E. upgrading to better materiel, increasing the diameter and/or pitch, upgrading to a 4 blade, cupping ect. However the worst effect is altitude…Lack of oxygen makes for terrible performance.
Here is a chart that can help
Altitude chart versus minus in pitch required
3000ft…-1 in pitch
9000ft…-7 in pitch
I would suggest a composite propeller by Piranha and you can have a set a of blades with a lower pitch for boating at high altitudes.
Piranha composite propellers are superior to any aluminum. Piranha propellers were developed with three things in mind: durability, performance and affordability. A key feature is that the blades are replaceable. You can change the diameter and the pitch, save on the costs involved with propeller repairs, not to mention the potential damage to your gear case. With Piranha you can have some spare blades in the boat for a quick and affordable repair
We also sell the hi-grade aluminum propellers from Michigan wheel and Solas
And of course Powertech Stainless and aluminum propellers
You can call 1-866-799-7767 to place an order