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Bow lift. VS. stern lift.

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Old 04-26-2008, 08:33 PM
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Default Bow lift. VS. stern lift.

What gives more bow lift..? if the prop is lower in the water or it's higher?
IE. if the center line of the prop shaft is higher, (like an Imco shorty) will that provide bow lift? or stern lift. ?
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P
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Old 04-26-2008, 09:39 PM
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i think some of it has to do with what way the props spin, wether they go in or out
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Old 04-26-2008, 09:53 PM
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Originally Posted by showtime83 View Post
i think some of it has to do with what way the props spin, wether they go in or out
CR.. Out.. Port>>> conter clock. Starboard.. clock.
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Old 04-26-2008, 09:55 PM
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The higher the propshaft centerline is the less bowlift... Meaning that if you install a shorty you will generally loose bowlift & create more sternlift.... Prop selection also plays a major role in bow & stern lift.... Style of blade : round ear or cleaver , Diameter , rake , ect..

Hope this helps answer your question....
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Old 04-26-2008, 09:58 PM
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As far as spinning the props in , or spinning them out.... usually spining the props in will create more bow lift than spinning out... Not sure what kind of drives you are running but if the boat has bravo's on it that is something that can easily be switched to see wich way the boat handles & runs best

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Old 04-26-2008, 11:13 PM
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THe boat is being rigged with shorties and I was hoping for bow lift. THis boat needs it. I am aware of the prop stuff, but I might have to turn them in. But.. I also now, that turning night loose some stability. I just have to experiment.
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Old 04-26-2008, 11:25 PM
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Could someone explain why the rotation of the props affects bow lift?

Michael
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Old 04-27-2008, 12:59 AM
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Quote:
Originally Posted by PARADOX View Post
THe boat is being rigged with shorties and I was hoping for bow lift. THis boat needs it. I am aware of the prop stuff, but I might have to turn them in. But.. I also now, that turning night loose some stability. I just have to experiment.
Please forgive any oversight but is this a boat that you have ran already ? & ifso are you adding the shorties to try to gain bowlift ??

What boat is it ?? & if you are going from standard lowers to shorties what is the X-dim. at now with the standards ?
& what shorties are you going with ? -1" , -2" ... ?

I don't want to be the bearer of bad news by any meens but if you are putting shorties on with the sole intentions of gaining bow lift I am not sure you are going to be very happy with the results
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Old 04-27-2008, 01:31 AM
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Quote:
Originally Posted by Michael1 View Post
Could someone explain why the rotation of the props affects bow lift?

Michael
I am sure somebody on here can explain it much more gracefully than myself but here is a simple analogy that may or may not help , or even make sense for that matter but I will give it a shot anyways... Take 2 gears & set them togather & then rotate both of them inwards (towards each other) & then notice which way they want to travel (downwards) Then take the same gears & rotate them outwards & see which way they want to walk (upwards).... Now put those gears (or props) on the transom of the boat & 1 rotation has a tendency to put pressure downwards & plant - with the other rotation having a tendency to put upward pressure on the transom causing stern lift...

Now with that in mind not all hulls will respond or the react the same & prop rotation will definitely change the handling characteristics of most boats... Twins or single engine....Even around the docks... Thats the good thing about bravo's : They make it easy to swap rotation so you can find out exactly what works best for your particular application , setup , & driving style....
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Old 04-27-2008, 07:26 AM
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Good question Paradox, I always wondered about the effects of a hi X on bow lift. Anybody have a 3/4"-1" spacer for a bravo?
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