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Suzuki DF150 prop question
I've got a 2006 War Eagle Tomahawk 962 (pad hull) with a 2006 Suzuki DF150. I'm currently running a 4 blade 14.5" diameter 28 pitch prop at 6000 RPM'S and 50 mph. From what I've read, I should be hitting mid to upper 50's with this setup. I've also been told a 28 pitch is too large of pitch for the 150, but haven't been told exactly what to run. I have friends with the same motor on similar boats running 57-60 mph with a 22 pitch prop. Should I go up in diameter, down in pitch amd with a 3 blade for more speed? I just don't feel like my boat/motor is living up to it's full potential. Any help is appreciated.
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Moderator
Your gear ratio is the reason you need all of that pitch. Your friends are not running that ratio with props and speed mentioned.
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My friends have the exact same motor (Suzuki DF150) that is on similar boats. If it's the same motor wouldnt they have the exact same gear ratio, and they are running 21 and 22 pitch props.
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Moderator
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My question wasn't should I try one of my friends 21-22 pitch props. My current prop is a 28 pitch 4 blade and 14.5" diameter. If I wanted to go with a 3 blade 16" what pitch would I need and would it increasing speed any. The props they are running wont work because they are 14.5" diameter and I overrev using them.
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Moderator
I'm trying to help you, But you are not listening... You have a 2.5:1 gears and 6000 rpm max motor... You are showing 24% slip now... You may benefit from more diameter and or lowing the motor. To go 55 mph, You would need a 26P prop at 6000 rpms and 10% slip.
Please read links and learn how to use the prop slip calc.... The object is to turn the most pitch you can to the max rpms with the correct motor height, trim, and lift for the load that your hull needs.
http://www.go-fast.com/prop_slip.htm
http://www.go-fast.com/Prop_Slip_Calculator.htm
PS... Your friends would need to spin the 22P to 7200-7700 rpms to see 57-60 mph with the same ratio as you.... It don't add up! Not possible.
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Moderator
Dont believe everything you hear or read on the internet.
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So you think I'd be okay to get a 3 blade 16" diameter 26 pitch?
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Moderator
I'd try lowering your motor some first.... That amount of slip is bad. Unless your tach is wrong and reading high... And is actually turning 5200 rpms.
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Moderator
Check your tach for accuracy and measure your motor height...
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I will check the pad to prop height. What range should it be in? Also when idling my tach is at 750-800 which from what I've read is normal. The motor is on the second hole from the top now.
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My pad to prop height it 4.5"
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I have a built in 8" setback on my boat too if that helps.
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Moderator
4.5 should not be slipping 24% with a 4 blade. Has the prop ever been damaged or repaired? Idle rpms is not a good way to check top end rpms.
How much does your hull weigh? I looked it up at 19.33 ft long and 1,200 lbs....
Do you have a super heavy load? Power poles etc? How much do you weigh?
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Moderator
I think a Yamaha 27T1 VX-Max would be perfect. I don't know if it would fit or what it would take to fit. Solas makes a copy (Scorpion)as well as PowerTech (VMX) that I'm sure would fit. I don't think they are quite as good and may run stiff in pitch.
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I would say a moderate load. I have dual power poles, two deck seats, rods holders,24v Ulterra, and me (200 lbs).
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Moderator
55 mph might be a stretch for your rig/load
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Member
War Eagle may be a pad hull - but isn't built to be a runner. It's built to run duck sloughs and turn on a dime with change back. Too many BIG turning strakes on the bottom to be a truly fast hull. It is faster than most through shallow rivers and creeks because it's extremely nimble and won't slide in turns like most aluminum rigs.
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I just ordered a Power Tech RKR3 in 26 pitch. Their trade in program is pretty good so even if they pitch doesn't work I can trade it in for $50.