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two-air 03-26-2002 11:24 PM

drive ratio
 
I have a 99 HP-500 with a Bravo-1 drive. What is the drive ratio # (I am trying to use one of those performance analyzers and that is the only peice of data I am missing)

TomFTM 03-26-2002 11:32 PM

Most likely 1.5 ratio. What type of boat?

two-air 03-26-2002 11:53 PM

Warlock 29, what would anyone guess would be apropriate prop slip for this engine boat combo?

SteveDavid 03-27-2002 12:39 AM

Have you run the boat yet? If so, that would give you your actual slip. Subtract your actual speed from theoretical speed and that becomes your slip. That number will be dependent on prop type, X dimension and drive type (shorty, nosecone, std. bravo lower, etc) . However, because you're only using your boat for the formula, your set up remains constant.

If you haven't run it and you're just looking for a number to plug into your analysis, use a range of from 11% to 20% with the real world median probably being something <14%. Granted, that's a wide range, and as hard as it might be to believe, I think you'll find it pretty accurate after your in water test.

You have a great hull, with mountains of hard offshore experience behind her. Have a ball!

Steve

Griff 03-27-2002 12:54 AM

Its probably a 1.5 ratio. I would think your slip should be around 12-13% for the step hull and 14% w/o the step.

Reckless32 03-28-2002 01:38 AM

Typical factory performance hulls/props will see 10-12% slip factor...


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