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kab
01-04-2002, 03:39 PM
Whats the formula for figuring your prop slip again? Sorry for asking again. Just had my new DCB out at havasu ran 84 at 4800 rpm with a 30 bravo 1 prop. Still trying to get break in hours on it.

spectras only
01-04-2002, 03:53 PM
http://www.boatpropellers.com/propcalc.html
[This message has been edited by spectras only (edited January 04, 2002).]

spectras only
01-04-2002, 04:36 PM
This is another one; www.boatramp.com (http://www.boatramp.com)

MIKEHTMSR24
01-04-2002, 06:57 PM
pitch x rpm
--------------
1056 x gear ratio
30 x 4800
------------- = 90.91 mph less slip
1056 x 1.5
90.91 - 84 / 90.91 = 7.6 % slip
If gear ratio is 1.36
Slip is 16.22%

Reaper1
01-04-2002, 09:03 PM
kab, what kind of power are you running in your DCB? Just curious and bored on a Friday night.

sofa king smooth
01-05-2002, 09:28 AM
I have a 28ft conquest deck. Bravo xr imco stand off box and a 2inch shorter lower unit.My motor made 757 on the dyno.Irun a 30 pitch bravo slightly dinged and at 5600rpms gps reads 91mph.Does this sound right or should I be getting more.What is my slip.I run 1.5 gears.

sofaking
01-05-2002, 10:39 AM
your stealing my name joe

sofaking
01-05-2002, 10:41 AM
you should be hustler anyway you pimp

sofa king smooth
01-05-2002, 11:18 AM
wade i was hopping you were not on this board so i wouldn't get snagged.The name just to funny had to steal it.By the way you the man.

Chet 17
01-05-2002, 06:27 PM
Yo Smoothy, the formula reads 14.2% at the numbers you gave,
Now if it were at 10% it should be 95.5 mph
And at 12% it would be 93.3 mph
Now if you can get those R's up your in a new whole ballpark....
Hope it helps
Late
Chet

kab
01-07-2002, 06:56 AM
Reaper1-I have a DCB Mach 26 open bow with a 502 efi w/whipplecharger on it. So far I am very pleased with it. I believe it is set up with around 4-6 pounds boost.