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Old 08-01-2008, 08:05 AM
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Default prop slip

I've seen the Bam site for figuring prop slip...
my question is how do you reduce it??
thanx
mike
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Old 08-01-2008, 09:02 AM
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what set up are you running now? give us a little info: and we can give some input, every boat is different and so are props, tell us more.
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Old 08-01-2008, 01:00 PM
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Changing props or changing drive height is the most common way to reduce slip.
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Old 08-01-2008, 01:02 PM
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Ok....
'03 280 silencer 496 ho
bravo 1 x with 1.50
labbed 26 bravo 1
w.o.t 4900rpm
speed is 64-65 mph? - I may need to recheck- will do this weekend

thankx,
mike
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Old 08-07-2008, 10:06 AM
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yep...confirmed speed was 64 mph, 4900rpm, bravo 1 labbed, 1.5 xr drive, 496 ho
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Old 08-07-2008, 04:46 PM
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Originally Posted by verbi69
yep...confirmed speed was 64 mph, 4900rpm, bravo 1 labbed, 1.5 xr drive, 496 ho
Bravo I props are not true pitched. I have been told that typically for a 26 pitch that you should use a pitch number of 25.3. Doing that your slip factor is 18%. I believe anything over 15% is considered high. I am assuming that you are using a gps speedometer. Anything other than gps is a best guess. This is the formula that I used.

4900 (rpms) X 25.3 (pitch) divided by 1.5 (ratio) divided by 1056 (factor) = 78.264 X 82% (slip) = 64.176 mph.
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Old 08-07-2008, 05:52 PM
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I just spent an entire day testing props I was able to borrow......5 blade maximus got me as low as 10.9% at 4,000 and at WOT it was 11.X (can't remember)!!!!!



Looks like I'm buying anopther set of props!!! (My bravos came in at almost 19%!!!!!)
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Old 08-08-2008, 07:45 AM
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Holly....how long do I need to keep scratching my head???
And yes with the gps speed...
Thankx guys....
mike
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Old 08-08-2008, 07:46 AM
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So with too high a pitch what is the next step?????
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Old 08-08-2008, 10:42 AM
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Originally Posted by verbi69
So with too high a pitch what is the next step?????
Take your prop to a prop shop and tell them what you want to achieve.
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