Prop Rotation Vs. Bow or transom lift!!
#1
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Prop Rotation Vs. Bow or transom lift!!
Does props turning in to each other create transom lift or bow lift???? And do props turning out create bow lift or transom lift!!!!! I know that round ear props give bow lift and cleaver style props give transom lift but what about rotation???
#6
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If you are talking about most V bottoms I would have to agree with Scarab 105.
When turning the props in (top of the props toward each other) the stern tends to be lifted. This is evident when the stern starts to feel light at speed. Usually there is an increase in top end speed but some boats are very much out of control.
Some boats perform well with the drives turning in. The best thing to do is to try turning both in and out and see how the boat feels. You may find that different boating conditions may dictate whether you turn the props in or out for the day.
Just don't forget the boat moves in the opposite direction when the prop rotation is reversed from it's original set-up.
If you want to change the prop rotation and you have Alpha drives or outboards you have to move the lower unit from one drive to the other, with the Bravo drive you can just put the shfter in the opposite direction.
Matt
When turning the props in (top of the props toward each other) the stern tends to be lifted. This is evident when the stern starts to feel light at speed. Usually there is an increase in top end speed but some boats are very much out of control.
Some boats perform well with the drives turning in. The best thing to do is to try turning both in and out and see how the boat feels. You may find that different boating conditions may dictate whether you turn the props in or out for the day.
Just don't forget the boat moves in the opposite direction when the prop rotation is reversed from it's original set-up.
If you want to change the prop rotation and you have Alpha drives or outboards you have to move the lower unit from one drive to the other, with the Bravo drive you can just put the shfter in the opposite direction.
Matt
#7
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I concurr that turnginin on my v bottom creates stern lift
I switched on a stock 272 formula to turning in one day. the boat scared me. i thought i was driving a hi-low at 50mph. boat was turning on it's bow, all squirely I switched back that day.
surfacing type drive configs seem to like turning in to gain some top end, but in my case. it was unsettling with my deep bravos.
ramb
I switched on a stock 272 formula to turning in one day. the boat scared me. i thought i was driving a hi-low at 50mph. boat was turning on it's bow, all squirely I switched back that day.
surfacing type drive configs seem to like turning in to gain some top end, but in my case. it was unsettling with my deep bravos.
ramb
#8
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On vee's, inside rotation ( port: CW, starboard
CCW as viewed from the stern) ='s bow lift.
Once the blades pass the skeg, and get into
the "deeper" water, and start the upswing, they're
"digging in", which gives the drives more leverage.
And yes, handling is poorer around the
docks when turning in.
Like Matt has said, you should try it and see
what works best.
It's a simple test if you have Bravo's.
jt
CCW as viewed from the stern) ='s bow lift.
Once the blades pass the skeg, and get into
the "deeper" water, and start the upswing, they're
"digging in", which gives the drives more leverage.
And yes, handling is poorer around the
docks when turning in.
Like Matt has said, you should try it and see
what works best.
It's a simple test if you have Bravo's.
jt
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My experience matches jt29s description. Turning in created significant bow lift on my boat. It causes the wheels to want to walk down the vee created by the hull, out causes the wheels to want to walk up the vee created by the hull. Mine is safer and faster turning in. It was tending to bow steer spinning out at WOT.
BT
BT