The pitch of your propeller determines how fast your boat busts out of the hole; it also affects how fast you accelerate. But the same pitch does not do both. Determining the best pitch for your boat’s purpose is like fine-tuning your recipe for homemade barbecue sauce: too spicy and it will blow your eyeballs out. Too bland and your barbecue becomes as boring as watery ketchup.
For the record, a boat propeller’s pitch is the theoretical distance a propeller travels in one revolution. Pitch affects the performance of a prop more than any other aspect and is measured in inches. A 23-pitch propeller, for example, would move forward 23 inches in one revolution. When choosing your propeller, you will hear the terms “high pitch” and “low pitch,” and each type has its own specific characteristics. A higher pitch, for example, delivers greater top speeds, but slower acceleration. Conversely, a boat propeller with a lower pitch gives you faster acceleration and a better hole-shot.
Because the same pitch does not give you both hole speed and fast acceleration, the first, best consideration when choosing your propeller pitch is the performance you expect from your boat.
If you use your boat for wake boarding and water skiing, for example, you’ll want a lower pitch prop, because it will give you the hole shot and acceleration you need.
On the other hand, if you use your boat for fishing or diving, you’ll want a higher pitch to give you the speed to travel distances with all your gear and equipment. Similarly, large boats, such as houseboats and cruisers, displace greater amounts of water and need a higher pitch propeller to achieve power at lower RPMs.
Below are the basic characteristics of low and high pitch boat propellers. For more information on propellers, link here to the Savvy Boater’s Boat Propeller How-To Guide.
Low Pitch Propeller: The lower the pitch, the faster you will accelerate out of the hole. Your top speed, however, will be slower, as your engine will reach its maximum RPM at a slower speed.
- Improved hole shot
- Better acceleration
- Better pulling power
High Pitch Propeller: With a high pitch propeller, you will achieve greater speeds but slower acceleration.
- Greater top speeds
- Slower initial hole shot
- Less acceleration
Other considerations: If your pitch is too high, it will “lug” the engine, reducing both top speed and performance. If your pitch is too low, it will cause the engine to exceed the specified RPMs at the top end. Sustained operation in either of these situations will cause catastrophic damage to the engine.
Your boat should be responsive to your unique expectations and much of that rides on the performance of your propeller. The propeller, in turn, is the most technical and intricate component of your boat. By taking the time to select the right boat propeller pitch, you’ll be able achieve optimum performance, safety and enjoyment from the use of your boat.