Prop suggestions....
03-01-2011, 11:05 AM
#11
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03-01-2011, 09:21 PM
#12
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Say your motor peaks torque at 4600 and peaks in horsepower at 5600. Where do you try to prop your rpms to?
Thanks,
Allen
Last edited by 29scarab10; 03-02-2011 at 12:30 PM.
03-01-2011, 10:51 PM
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I've always tried to prop close to peak HP. But you need to be sure your valvetrain is up to the task. Propping too close to peak torque is hard on the drives, and can make for ill handling. I have a friend who ran 700hp 540's thru TRS drives for many years with no failures. He spun the motors around 5900. I think that was the key to keeping them drives together. Some guys cringe at the idea of anything over 5k rpm. A properly setup hydraulic roller can turn 5600-5700 all day. Solid rollers even higher.
03-02-2011, 07:54 AM
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I've always tried to prop close to peak HP. But you need to be sure your valvetrain is up to the task. Propping too close to peak torque is hard on the drives, and can make for ill handling. I have a friend who ran 700hp 540's thru TRS drives for many years with no failures. He spun the motors around 5900. I think that was the key to keeping them drives together. Some guys cringe at the idea of anything over 5k rpm. A properly setup hydraulic roller can turn 5600-5700 all day. Solid rollers even higher.
Mike can't wait to see the new set up and go for a ride
03-02-2011, 10:17 AM
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I've always tried to prop close to peak HP. But you need to be sure your valvetrain is up to the task. Propping too close to peak torque is hard on the drives, and can make for ill handling. I have a friend who ran 700hp 540's thru TRS drives for many years with no failures. He spun the motors around 5900. I think that was the key to keeping them drives together. Some guys cringe at the idea of anything over 5k rpm. A properly setup hydraulic roller can turn 5600-5700 all day. Solid rollers even higher.
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03-02-2011, 12:48 PM
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Allen, Joe is right here. Generally speaking, your peak hp will be 1000-1200 rpm over your peak torque. If your peak hp is around 56-5700 rpm, you would'nt want to spin the prop much higher rpm than that. Guessing that you have bravo drives, rpm does'nt hurt the drives, it's putting a big load on them that kills em. They'll last alot longer spinning the props at 57-5800 rpm, than at 4900-5000 rpm at wot. You'll just lose some mid range cruise speed. The bigger the prop, the better the cruise, but you'll sacrifice speed on the top. I'm guessing that you would need something in the 26-27 pitch area.
I typed that wrong. Motor peaks torque at 4600 and makes peak horsepower at 5600.
Thanks,
Allen
03-02-2011, 05:37 PM
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Allen, I believe that's what you said the first time, you were correct, and that sounds about right. 56-5700 you'd want wot.
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03-03-2011, 09:44 PM
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Mike, there's a pr. of 5 blade 28's Hydromotive P5X's in the swap section. Might be just what you'll be lookin for. Check em out.
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03-04-2011, 11:47 AM
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Had a similar set up on our last 35... 1 step, standoff boxes, 585 hp per side, 1.5 gears, max hp at 5600 rpm... no shorties, though..
29 Quad IVs 65MPH @4500rpm, 76@5000, Hit rev.lim.(5600) 85mph
29 P-5's 72 @4500, WOT@ 5200 87.4mph
31 5bl(CNC) 76@4500, WOT@ 5200 90mph
Throttle up
Hope this helps, we ended up with the Throttle Up 5 blades, but a labbed pair of Hydro P-5's was very close in overall performance.
Carder
29 Quad IVs 65MPH @4500rpm, 76@5000, Hit rev.lim.(5600) 85mph
29 P-5's 72 @4500, WOT@ 5200 87.4mph
31 5bl(CNC) 76@4500, WOT@ 5200 90mph
Throttle up
Hope this helps, we ended up with the Throttle Up 5 blades, but a labbed pair of Hydro P-5's was very close in overall performance.
Carder
Last edited by Carder; 03-04-2011 at 11:52 AM.
