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Mph lost goin to b max drive from xr drive

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Mph lost goin to b max drive from xr drive

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Old 04-03-2015, 10:53 AM
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Default Mph lost goin to b max drive from xr drive

Right now I have xr drives with 2 inch imco shorties and my 42 fountain is running mid to low 90s. I'm swapping over to b max uppers with imco 2 inch shorties. How much mph if any will I loose swapping to bmax
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Old 04-03-2015, 10:57 AM
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I would think none. It's the same gear set.
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Old 04-03-2015, 11:23 AM
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Xr 1.5 bmax 1.36 but goin to smaller props due to gear ratio change
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Old 04-03-2015, 12:51 PM
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Originally Posted by indysupra
I would think none. It's the same gear set.
upper gear is much bigger 5" if I m correct so the b max will eat more hp then the xr and the ratio change could also hurth a little bit .but its much better not to worry to blow a drive !
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Old 04-03-2015, 03:06 PM
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2-4mph from what I hear....
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Old 04-03-2015, 03:15 PM
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Originally Posted by slippy0217
Xr 1.5 bmax 1.36 but goin to smaller props due to gear ratio change
it may just be a lateral move. Going to the smaller prop on a taller ratio is going to benefit from having a more efficient prop in the water. What you lose in parasitic loss you may gain back in less prop slip. (I have nothing to back any of this up . . . . just trying to be an optimistic fellow boater lol)
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Old 04-03-2015, 03:45 PM
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Originally Posted by glassdave
it may just be a lateral move. Going to the smaller prop on a taller ratio is going to benefit from having a more efficient prop in the water. What you lose in parasitic loss you may gain back in less prop slip. (I have nothing to back any of this up . . . . just trying to be an optimistic fellow boater lol)
I agree with that theory, Slippy what pitch prop were you running with the 1.50 ratio?
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Old 04-03-2015, 03:54 PM
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slippy what year Fountain?
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Old 04-03-2015, 06:40 PM
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Going from a 1.5 to a 1.36 normally requires about 3" less pitch. I would go down 4" switching to the BMax.
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Old 04-03-2015, 06:43 PM
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Really doesn't matter the strength increase is worth the money!
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