Couple years ago I bought a Ranger Angler 1875 with a Suzuki 175HP. It came with a 25 pitch prop which I thought was a bit high. I talked Ranger into swapping the 25 for a 21. It seems to be performing well but I still think its a bit sluggish at top end. Do any of you prop guys have any tips on what pitch performs best?
You have to pick which characteristics are most important to you. A higher pitch will give you higher top end speed while a lower pitch will give you more torque. Each inch of pitch will lower your rpm by roughly 200rpm so you should have about an 800rpm difference between a 21 and a 25. If you find out what the maximum RPM of your motor should be and what your current maximum RPM is with a 21 you can roughly figure out what your options are. If you go with a higher pitch for more speed a 4 bladed prop might help with hole-shot a bit since you’ll be losing some of the low end power.
When I bought my boat it had too high of a pitch prop on it (21 pitch). The whole shot sucked and top end was 30 mph. I dropped to a 15 pitch and the hole shot was great and top end was 40 mph. My engine just didn’t have enough power to push the 21 pitch prop. So a bigger pitch doesn’t always mean faster. You need to figure out your max rpm and find a prop that stays just below it at WOT.
When I bought my boat it had too high of a pitch prop on it (21 pitch). The whole shot sucked and top end was 30 mph. I dropped to a 15 pitch and the hole shot was great and top end was 40 mph. My engine just didn’t have enough power to push the 21 pitch prop. So a bigger pitch doesn’t always mean faster. You need to figure out your max rpm and find a prop that stays just below it at WOT.
So you’re saying my plan of hitting 150mph with my 80 pitch is not going to work….? 
<div class=”d4p-bbt-quote-title”>Tuma wrote:</div>
When I bought my boat it had too high of a pitch prop on it (21 pitch). The whole shot sucked and top end was 30 mph. I dropped to a 15 pitch and the hole shot was great and top end was 40 mph. My engine just didn’t have enough power to push the 21 pitch prop. So a bigger pitch doesn’t always mean faster. You need to figure out your max rpm and find a prop that stays just below it at WOT.So you’re saying my plan of hitting 150mph with my 80 pitch is not going to work….?
All depends on how many ponies you can afford to feed.
What is your top end and RPM for each prop? A Merc or Yamaha 175 on yout boat would most likely run max RPM with a 19 pitch and top out around 50. Suzuki’s have deep gearing and can typically swing props with more pitch. You could try a 19 if you need more RPM.
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