Re: Prop pitch question
Best to decide if one wants SS (steel) or Aluminim prop. SS are expensive and being expensive, often used in deep water. Aluminum is much lower cost. And, can be easily replaced - if damaged in shallow water.
SS and Aluminum act differently. For example, 21" Aluminum is like a 20" (and some 19") SS. And, not all SS or Aluminum "brands" act the same either. For example, brand xx aluminum acts differently compared to brand zz aluminum (of same cup and other detailed shape design). 3-blade and 4-blades (of same material) are not direct comparisons either. For example, a 3 blade 19" acts like a 4 blade 17". As a general comment, 4-blade has better hole-shot grip and 3 blade has better fuel savings at higher RPM.
A few things about my combo (that could be applied to yours):
- Boat came factory with 3-blade 21" P. This was based on empty boat with single rider. ya, perfect white board world.
- Boat pulls "average" with 3-blade 19" aluminum. OK hole-shot and good gas savings at upper RPMs. For my boat, 3-blade 19" aluminum was a good starting point. Then, decide variances up/down from this baseline.
- Boat pulls "much better" with 4-blade 17" alumimum. Much better hole shot and feels better under 2/3 throttle. And, 4-blade is much faster to plane as well. And, 4-blade has much better steering control in loading ramps / loading area in "R" gear as well. Since I do most time doing crusing under 2/3 throttle with tubing, I like my boat's 4-blade 17" much better. Now, I keep the 3 blade 19" Aluminum as backup prop - for my shallow water areas. As default, I use the 4-blade 17" Aluminum prop and visually keep RPMs under 4,500s as well.
With above in mind, do pick the best prop for your "most often" driving conditions as well. If mostly under 2/3 throttle with tubing / boarding, do think of 4-blade with less pitch - which has better grip. Or, think of 3-blade for faster upper RPMs for better crusing distance. Props is like tires on the vehicle. re: Which is the "most often" conditions and pick the size that works best for majority of time. And, have a different size backup prop that one can switch out - for those less often special trips.
Hope this helps..
