Prop pitch and fuel economy?

[Dan L]

When running a 25" pitch prop as compared to a 23" prop I am getting about 3 - 4 MPH more speed at 4000 RPM's. I assume this means I am getting better fuel mileage with the 25" prop. Is this correct? This also means I am only running 5400 RPM's at top speed with two guys and gear. The rpm range for my motor is 5000 - 6000 RPM's. Is that lugging the motor to much. Most of the time I am criusing around at the 4000 RPM"s range.

[croixflats]

I would think the extra load on the engine means your burning more fuel especially coming out of the whole getting up on plain.

Remember Aa truck with taller gears in the rear end may get better gas mileage but it has a transmision to get you at optimal opperating speeds.

[marine_man]

I would go back to the 23" prop to get your RPM's back up where they should be. I agree with croixflats that you're probably burning more fuel because you're lugging the engine pretty good.

If you get a good load of people / gear you're going to have a lot slower holeshot and will burn more fuel there too.

marine_man