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Reducing slip?

Old 05-30-2011, 09:07 PM
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Default Reducing slip?

I want to reduce my slip numbers. Any ideas?
33' no step hull, twin 525's. bravo XR with ITS.

28" labbed, 81 MPH at 5300+- RPM.
30" labbed 83 at 5200 RPM.
32" labbed 81 at 4950 RPM.
All numbers in calm waters. Boat will go faster when its in chop or rough seas, and RPM's go up a bit, but the slip numbers are high no mater what props I use.
Any ideas? I had the boat at 85, but any other props then Bravos might work?
thx
P
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Old 05-31-2011, 01:31 AM
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First of all when calculating slip for Bravo props, you need reduce the stamped pitch by one inch when you plug in the numbers.

The 28 is at 10%
The 30 is at 13%
The 32 is at 16%

The 32 is a little high, but the 28 and 30 are fine for a straight V bottom.
Reducing slip increases the bite of the prop and thus stresses the drive more also.
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Old 05-31-2011, 01:39 AM
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Originally Posted by Griff
First of all when calculating slip for Bravo props, you need reduce the stamped pitch by one inch when you plug in the numbers.

The 28 is at 10%
The 30 is at 13%
The 32 is at 16%

The 32 is a little high, but the 28 and 30 are fine for a straight V bottom.
Reducing slip increases the bite of the prop and thus stresses the drive more also.
Griff, I've heard that you want to be able to just hit the rev limiter. Thoughts?
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Old 05-31-2011, 01:43 AM
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Who the heck cares about slip...which prop is fastest..and working best on your boat.

As soon as I stopped concentrating on slip...and started paying attention to which props were the fastest...and made the boat handle the best...my boat started getting a lot faster.

Chris

Last edited by CB-BLR; 05-31-2011 at 01:48 AM.
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Old 05-31-2011, 11:41 AM
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Originally Posted by Keytime
Griff, I've heard that you want to be able to just hit the rev limiter. Thoughts?
If you bump it a little on a cool day with light load of fuel, then that is fine. You just don't want to be hitting it all the time at WOT under normal summer boating conditions.
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Old 05-31-2011, 11:42 AM
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Originally Posted by CB-BLR
Who the heck cares about slip...which prop is fastest..and working best on your boat.

As soon as I stopped concentrating on slip...and started paying attention to which props were the fastest...and made the boat handle the best...my boat started getting a lot faster.

Chris
X2
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Old 05-31-2011, 11:52 AM
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Originally Posted by Griff
Reducing slip increases the bite of the prop and thus stresses the drive more also.
Not entirely true. Slip is vibration. The more slip, the more vibration on your drive.
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Old 05-31-2011, 11:50 PM
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Originally Posted by CB-BLR
Who the heck cares about slip...which prop is fastest..and working best on your boat.

As soon as I stopped concentrating on slip...and started paying attention to which props were the fastest...and made the boat handle the best...my boat started getting a lot faster.

Chris
Test, test, test.
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Old 06-01-2011, 09:07 AM
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Originally Posted by Boomer35
Not entirely true. Slip is vibration. The more slip, the more vibration on your drive.
Think about this for a minute....so you are saying that with your boat sitting on the trailer...with the prop spinning in the air...which would be 100% slip of your prop...your drive would have the most vibration?

Your statement doesn't make sense.

Chris
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Old 06-01-2011, 09:27 AM
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Originally Posted by CB-BLR
with your boat sitting on the trailer...with the prop spinning in the air...which would be 100% slip of your prop...your drive would have the most vibration?

Try it and find out but I think there would be alot of vibration with that scenario but it is not really an accurate representation of "slip", and that would be under completely different conditions that normal "slip" which he is refering to.
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