Why would a high Prop pitch not be better then a lower one. If I had a 15" pitch at idle would it not push the boat faster then a lower pitch of 8" thus using a lower RPM and saving fuel?
Well, most of those pontoon boats have a certain hull speed, pushing the throttle down farther after reaching that speed usually does nothing more than lug the engine and waste fuel. You mention the speed limit of 5mph, I would guess your friend is trying to exceed that limit.
Just get an Engine designed for the application. All this talk of 5000RPMs and 4 strokes is making me ill 😆 :
Not enough? Get two. It will burn a gallon every two hours but you can buy alot of gallons with the money left over from a 100 dollar engine.
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