Offshoreonly.com - Bravo basics in gearing

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Appreciate the explanation 33. I couldn't find that anywhere.
Matt

Quote:

Originally Posted by Griff (Post 4429235)

If you added more than about 100-120hp, then the gear change from 1.65 to 1.50 will probably not be enough to reuse the props you have anyway.

It was slightly over-propped to begin with and the gear change calculated out to be a 2pitch difference. I've seen some B1 top halves go for pretty cheap and was entertaining the idea of grabbing one to see how things worked out before going big on a whole new drive. I think that I may end up jusr upgrading the drive and start swapping props to get the right fit.

Roughly and generally speaking, is a B1X drive good for about 650hp on a 27' 5Klb open bow boat, or should I just head straight to the classifieds for an XR drive? From what I've read a billit top cap and plenty of cooling goes a long ways for longevity.

Are there ggod and bad years for bravos? My current unit is a 1996 OL unit.

Quote:

Originally Posted by kilo (Post 4430074)

How do you determine what ratio you are running? I have #6's and would like to learn.

We do it a different way. Turn the prop shaft 10 turns, count the input. Divide input count by propshaft turns (10) , so 15/10 = 1.5, 13.5/10 = 1.35, etc.

Makes it a little easier when the ratios are close.

Also the weak link in a bravo is the upper. So a second upper is what is most needed for a spare to get thru the weekend anyway...