[Fr. Frank]

Your gear ratio is fine. Your prop needs changing.

Allow me to use a pickup truck as an analogy. The differential gearing is analogous to the lower unit gearing, and the tire diameter is analogous to the propeller pitch.

If I want to apply torque to the pavement more quickly I can change out the gears in my differential from the current 3.73:1 to 4.10:1 gears. If I do this, I will have better acceleration under load, higher rpms at cruise, lower axle rotation for a given rpm, and better responsiveness to power inputs.

OR, I can change my tires on the rear to a smaller diameter tire, which changes my applied drive ratio just like changing the diff gearing. Dropping from my current 265x75-16 tires to 245x65-16 tires gives me almost the exact same effective results as changing to 4.10 gears.

On the other hand, if I want to have lower rpms at cruise and a higher top speed, I can change the diff gearing to the optional 3.45:1 gears. This will reduce my acceleration, but give me lower rpms at a given speed, and probably increase my top speed.

OR, I can change my tires on the rear to a larger diameter tire, which changes my applied drive ratio just like changing the diff gearing. Increasing from my current 265x75-16 tires to 285x70-16 tires gives me almost the exact same effective results as changing to 3.45 gears.

In both cases, changing the tire size when it comes time to replace the tires costs a lot less, and produces the same results.

If your current gearset is undamaged, you can more economically change your effective power to thrust ratio by just changing the prop size.