How To Choose Pitch
- Identify the make, model, year and horsepower of your engine
- Consult the owner’s manual to find the recommended wide-open-throttle (WOT) RPM range for your engine.
- Using the existing propeller, make a test run to determine the current WOT RPM and speed. Vary the boat’s trim angle for maximum speed. The boat should be loaded as it would under “normal” operating conditions. A full tank of fuel is recommended.
- If the current propeller isn’t within the manufacturers recommended WOT range, select a propeller with a larger or smaller pitch using the following rules:
- Adding 1 inch of propeller pitch will reduce WOT RPM by 150 to 200 RPM.
- Subtracting 1 inch of propeller pitch will increase WOT RPM by 150 to 200 RPM
- If you’re upgrading from a three-blade propeller to a four-blade propeller, remember that many four-blade propellers generally turn 50 to 100 RPM less than a three-blade propeller with the same pitch.