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View Poll Results: Turning in or out
I know turning out gives more bow lift 1 9.09%
I know turning in gives more bow lift 0 0%
I think turning out gives more bow lift and I just wanted to be involved in this thread 0 0%
I think turning in gives more bow lift and I just wanted to be involved in this thread 1 9.09%
This option is for stupid people 9 81.82%
Voters: 11. You may not vote on this poll

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Old 09-11-2011, 09:08 PM   #1
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Turn In or Turn Out

on a un stepped 21' monohull with 7' beam and the engines mounted at 19" centres turning which way is best?
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Old 09-11-2011, 09:29 PM   #2
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In on a cat lifts the back, so everything usually being opposite for a mono, I'd say in will give you bow lift!

Cleaner water onto the blades on their upward stroke, pulls the back down = bow lift.
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Old 09-11-2011, 10:24 PM   #3
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ta but you havent voted dude
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Old 10-11-2011, 12:07 AM   #4
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Id love to say I know turning in gives bow lift but I wouldnt bet my life on it!
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Old 10-11-2011, 06:57 AM   #5
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I know it's not what you asked, but turning out gives much better stability doesn't it? Theory being that the outer prop is always trying to turn you back level when you heel over rather than trying to make it worse if turning in.
As for bow lift, I have my theories (and I'd guess turning in gives more), but they're not based on fact or personal experience so I'll keep em to myself!

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Old 10-11-2011, 07:47 AM   #6
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FWIW I was always told that turning in pushes the water down giving stern lift and faster but less stable, turning out is more stable but slower - if I'm right you take your pick!
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Old 10-11-2011, 07:49 AM   #7
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My experience is (with old fashioned regular mono's) turn out, slower, but more stable in roll, turn in, faster, but less stable in roll. Swipes bears this out to the tune of a mph or so gain in speed turning in, though with Swipes, there doesn't seem to be a downside. Maybe we're not going quick enough to get tricky?

I think you have to just suck it and see.

JF
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Old 10-11-2011, 10:38 AM   #8
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Quote:
Originally Posted by Jon Fuller View Post
My experience is (with old fashioned regular mono's) turn out, slower, but more stable in roll, turn in, faster, but less stable in roll. Swipes bears this out to the tune of a mph or so gain in speed turning in, though with Swipes, there doesn't seem to be a downside. Maybe we're not going quick enough to get tricky?

I think you have to just suck it and see.

JF
Tend to agree with Jon, Turn in usually quicker but less stable, as pointed out by Larby turning out gives some righting force. Start turning out as its safer and when you want to go quicker swap.
Amount of bow lift is really a function of prop rake not rotation.
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Old 10-11-2011, 01:38 PM   #9
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I am turning out at the moment but in its little use i have had trouble getting the nose out, I have been offered to try some different props (thanks JF) but was just wondering if turning in may help? I'd heard that it was more unstable but wondered if that would be so much of an issue on a wider boat??
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Old 10-11-2011, 03:20 PM   #10
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Easy enough to swop the boxes over

Hydromotive QIV's have some wicked bow lift, so much that I stopped running one on my cat, scared the hell out of me a few times, had a good bit of stern lift too, picked the starboard sponson up and walked it a few times.
Would be a real nice prop on a twin rig, I'd say. its a big dia blade.
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