If we use a 24" pitch propeller and there was no slippage, both boats would
travel 12,000 feet every minute at 6000 RPM.

With the same propeller on each boat the 250 hp boat would over rev at WOT.
So the helmsman would have to back off to keep it at 6000. The difference in
weight of the motors is about 30 lbs. Probably not going to be much of a
factor. The 250 might get to 6000 more quickly, but once at 6000 I think
both boats would be traveling at the same speed.

Thanks again,
Injam

"Injam" wrote in message
news
Hello,

I'm trying to understand propellers.

If you have two identical boats, but the outboard horsepower ratings are
different. One boat has a 200 hp and the other a 250 hp. Both motors have
the same Gear Ratio. If the propellers are identical and the RPM of the
outboard is the same on each boat. Say 6000 RPM. Because of the weight
advantage will the 200-hp boat be faster than the 250 hp? I'm thinking
less weight less slippage otherwise they would be going the same speed.



Sincerely,

Injam