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Old 05-16-2012 | 12:37 PM
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Mine spinds outwards (34 baja, no steps), and am going to try them inward soon.
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Old 05-16-2012 | 04:26 PM
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Originally Posted by kragar
Why is it tricky around the docks when props are turning inward? Debating trying on my boss 302.
Reverse seems to have less effect....trimming the
drives positive helps a bit, but it's not as good as spinning out
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Old 05-16-2012 | 10:37 PM
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bigfarmer,


I Love your AVATAR pic! don't know why but it brings back old testing fly by brain pics to mind!!!!


kragar, thrust is less related to the transom when rotating inward.

JT, yes positive trim will direct the thrust below the transom....................

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Old 05-18-2012 | 12:41 AM
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Originally Posted by kragar
Why is it tricky around the docks when props are turning inward? Debating trying on my boss 302.
With props spinning outboard, when you oppose the engines to pivot, the prop-walk combines with the moment created by the thrust. I.e., you put the stbd in forward and the port in reverse, both props are spinning to starboard, which causes both props to walk to stbd, and the torque is twisting you to starboard also.

When you rotate in, the effects oppose each other. With the relatively small diameter props, with comparatively deep immersion we use, the prop walk effect is small.

I am spinning my Mercury Racing 4-blade cleavers inboard, and it pivots just fine. It probably pivots slower than it would going outboard, but who cares, I dock only once or twice per outing, and my previous boat was a single, so any additional maneuverability is just a bonus.

The boat will porpoise in the 60mph range, but you can stop it with the tabs. If I was set up to spend a lot of time running in the 60's, I'd probably consider turning them out. If you have the power, and are going to spend most of your time at higher speeds where you need the bow lift, turn them in.
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Old 05-18-2012 | 06:33 AM
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Originally Posted by tcelano
With props spinning outboard, when you oppose the engines to pivot, the prop-walk combines with the moment created by the thrust. I.e., you put the stbd in forward and the port in reverse, both props are spinning to starboard, which causes both props to walk to stbd, and the torque is twisting you to starboard also.

When you rotate in, the effects oppose each other. With the relatively small diameter props, with comparatively deep immersion we use, the prop walk effect is small.

I am spinning my Mercury Racing 4-blade cleavers inboard, and it pivots just fine. It probably pivots slower than it would going outboard, but who cares, I dock only once or twice per outing, and my previous boat was a single, so any additional maneuverability is just a bonus.

The boat will porpoise in the 60mph range, but you can stop it with the tabs. If I was set up to spend a lot of time running in the 60's, I'd probably consider turning them out. If you have the power, and are going to spend most of your time at higher speeds where you need the bow lift, turn them in.
coooooorect, mine spin inward on my flat bottom tiger, rotates slower but as you said doesn't matter (to me). it also matters if you have a side by side or a staggered set up..not impossible, just different.
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Old 06-03-2012 | 07:27 AM
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I'm going to try spinning my hydromotives in one I get my engines back in my Formula. Spinning out, my boat ran very flat so if I can gain a little bow lift by spinning in would be nice.
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