What Pitch To Buy

royncarol

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Feb 27, 2021
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I have a 3 blade 14 3/4 X 21 prop and want to go with a 4 blade for better handling. Do I stay with the same pitch as the 3 blade?
 

Sea Rider

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Sep 20, 2008
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I have a 3 blade 14 3/4 X 21 prop and want to go with a 4 blade for better handling. Do I stay with the same pitch as the 3 blade?
Usually one less pitch when going for a 4 blade prop. What's the max wot rpm achieved as loaded with the 3 blade 21 prop ?

Happy Boating
 

Texasmark

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Dec 20, 2005
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Other thing is like kind. If you change suppliers, models, or materials, you throw an unknown into the mix.
 

Scott06

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Apr 20, 2014
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Not sure what the wot is, it’s been a while since I had the boat out.
Determine what your current prop wot rpm is before buying a new prop. Where you land in terms of wot rpm will determine if you need to tweak pitch. if your current prop is at yhe upper end of your max recommended wot range then yes drop and inch of pitch and you should be ok. If its on the low side you may want to drop more than an inch.
 

QBhoy

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Mar 10, 2016
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Depending on the boat, I’m a great believer that most occasions these days, there is not much of an excuse for a 4 blade prop. None that can outweigh the Benefits of the great range of 3 blades available these days from the likes of merc. Unless you have a big heavy centre console thing at 30-40ft and a few big engines on the back...I really don’t see a need for them
 

Texasmark

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I like to cruise around 3000 rpm which runs me in the low 20's with a lot of slip...per Go-fast.com. I tossed my Laser II 20 P for a 4 blade Solace 19P 4 blade. Perfect. I am surprised it didn't cost me but a couple of MPH and maybe 3-400 RPM. Slip was still high like 15 (but I had a lot of boat in the water) and at about 5200 I was running 4% at abouty 42....was surprised it gave me that much top end considering the 4th blade, drop in pitch and that low a pitch......but that boat is wide, like 90+", has a 12% dead rise at the transom and the reverse chines really gets you lifted out of the water.....and dry....dryest boat I ever owned. Not much boat in the water at WOT.
 

Scott06

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Depending on the boat, I’m a great believer that most occasions these days, there is not much of an excuse for a 4 blade prop. None that can outweigh the Benefits of the great range of 3 blades available these days from the likes of merc. Unless you have a big heavy centre console thing at 30-40ft and a few big engines on the back...I really don’t see a need for them
I get my best results with a revolution 4, surprisingly including top speed, even bested the enertia on my boat. I haven't tried as many props as you but have tried 6.... i think it works in my application because i can fully trim out without blowing out, also get the holeshot benefit of a 4 blade. IMHO it comes down to how u prefer touse your boat.
 

QBhoy

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Mar 10, 2016
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I get my best results with a revolution 4, surprisingly including top speed, even bested the enertia on my boat. I haven't tried as many props as you but have tried 6.... i think it works in my application because i can fully trim out without blowing out, also get the holeshot benefit of a 4 blade. IMHO it comes down to how u prefer touse your boat.
Totally get that Scott. I should have mentioned about the Rev 4. That’s the exception to my personal rule...haha. It’s a hell of a prop that. But is just a tempest plus with an extra blade. If you’ve a normal boat that does well with a Rev 4...generally it will be even better mid and top end with the tempest 3 version.
As for losing grip...I get that a 4 blade would be good for this....but must admit I’ve never found either the tempest or the enertia to lose grip of the water. Maybe I’m not being hard enough on turns...but I likely wouldn’t be brave enough to turn the boat hard, anything over half throttle or so perhaps.
 

Sea Rider

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Sep 20, 2008
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Aside testing at close turns at speed must test under choppy, windy, wavy water conditions...

Happy Boating
 

achris

More fish than mountain goat
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May 19, 2004
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27,468
... there is not much of an excuse for a 4 blade prop. None that can outweigh the Benefits of the great range of 3 blades available these days ...
I can give you one, and it's why I'll always recommended a 4 blade in this location. Seagrass. 3 blades pick it up like a bad infection. 4 blade props tend to shed it much better.
 

QBhoy

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Mar 10, 2016
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I can give you one, and it's why I'll always recommended a 4 blade in this location. Seagrass. 3 blades pick it up like a bad infection. 4 blade props tend to shed it much better.
Sounds like a different craft all together is required then 😂
 

Faztbullet

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Mar 2, 2008
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15,931
Then this thing would make would either mince it or braid it into rope!!!
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