tork roll

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dick2256
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tork roll

Post by dick2256 »

My corvair motor sets on top of my boat,(pretty high)
I want to move my battery to the front some and also to the side to counter some of the tork roll.
standing in back of the boat the prop turns counter clockwise so my roll would be to the left
if I am thinking right, so I would need to move the battery to the right side of the boat.
Is this right? I have a mental about this for some reason. :dontknow:

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Re: tork roll

Post by DDPWRD »

You have good reason to be worried it could turn bad real quick. My recommendation would be to lower the engine that would change every thing for the better. That small 4 banger shouldnt have torq roll that bad.
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Deano
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Re: tork roll

Post by Deano »

That is backwards. As was pointed out, lowering the center of gravity will likely help more, but;

To counter the torque roll, you want the excess weight positioned a little to the port (left) side of center.

Now with that said, a little may very well go a long way depending on how wide the beam is or isn't.
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Re: tork roll

Post by glades cat »

Good ideas, but remember, torque effect occurs only when the engine/prop is accelerating or decelerating. Off-setting the battery, or any weight, only accounts for the acceleration portion. When you take your foot off the gas or shut-down, the biased weight may work against you, especially when combined with a swinging slow turn.
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Re: tork roll

Post by PeaRiverOpossum »

Torque roll is in the opposite direction of the prop. Sounds backwards I know. Think about it like this. The roll is the boats resistance to the prop rotation. Or imagine the boat and prop rotating in the same direction. In order to stop the rotation of the boat you must torque or turn the hull in the opposite direction of the prop. Clear as mud?

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Re: tork roll

Post by dick2256 »

DDPWRD wrote:You have good reason to be worried it could turn bad real quick. My recommendation would be to lower the engine that would change every thing for the better. That small 4 banger shouldnt have torq roll that bad.
corvairs are not 4 bangers they are inline 6 cylinder
I used to run it on a 14" jonboat with a 44" bottom and only tipped in 2 times in several years

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Re: tork roll

Post by broncobill »

Corvair motor is an Opposed 6 cylinder not inline. 44" of bottom sure isn't much in the water.
Last edited by broncobill on Fri Nov 29, 2013 1:23 pm, edited 1 time in total.

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Re: tork roll

Post by GMAC 76 »

x2....the corvair is an opposed 6cyl engine...just like an aircraft engine...with 6 separate steel cyls or barrels (3 on each side) and a head common to 3 cyls on each side...I ran one for many years and can not imagine much torque roll from that little engine unless the boat is really narrow and the engine really mounted high

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Re: tork roll

Post by dick2256 »

broncobill wrote:Corvair motor is an Opposed 6 cylinder not inline. 44" of bottom sure isn't much in the water.
yes I used the wrong word they are opposed not inline
sorry about that

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Re: tork roll

Post by Whitebear »

Right, Corvair is either 4 or 6 cylinder opposed. With torque roll to the CW direction since you said it turns CCW, then put your battery to the CCW side. You can drop the engine quite a bit if you can find a 3 or 4 blade prop for it. If you are going to re-prop the boat, I would get the prop selected before you relocate the engine so you can calculate where to move the engine to.

Keep on ind when you relocate the engine, you "may" want to relocate the rudders assuming they are in the optimal position to begin with. Since its a mild HP setup, that may make less difference than it might on bigger hp. Just something to keep in mind.
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Re: tork roll

Post by dick2256 »

Whitebear wrote:Right, Corvair is either 4 or 6 cylinder opposed. With torque roll to the CW direction since you said it turns CCW, then put your battery to the CCW side. You can drop the engine quite a bit if you can find a 3 or 4 blade prop for it. If you are going to re-prop the boat, I would get the prop selected before you relocate the engine so you can calculate where to move the engine to.

Keep on ind when you relocate the engine, you "may" want to relocate the rudders assuming they are in the optimal position to begin with. Since its a mild HP setup, that may make less difference than it might on bigger hp. Just something to keep in mind.
I think I need to hire a young secretary to do my typing and thinking for me.
facing the rear of the boat when you are outside of it my prop turns clockwise, most others turn counterclockwise. So having said that I need to put the battery some to the right side.
I am running on a 12'long-6'-6" wide bottom with 17" sides.so I should be ok anyway.
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Re: tork roll

Post by DDPWRD »

dick2256 wrote:
DDPWRD wrote:You have good reason to be worried it could turn bad real quick. My recommendation would be to lower the engine that would change every thing for the better. That small 4 banger shouldnt have torq roll that bad.
corvairs are not 4 bangers they are inline 6 cylinder
I used to run it on a 14" jonboat with a 44" bottom and only tipped in 2 times in several years
We both are wrong they are opposed six cylinders I forgot im thinkin VW
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Re: tork roll

Post by DDPWRD »

Sorry dick didnt mean to include you in that last post.
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Re: tork roll

Post by DDPWRD »

dick2256 wrote:
Whitebear wrote:Right, Corvair is either 4 or 6 cylinder opposed. With torque roll to the CW direction since you said it turns CCW, then put your battery to the CCW side. You can drop the engine quite a bit if you can find a 3 or 4 blade prop for it. If you are going to re-prop the boat, I would get the prop selected before you relocate the engine so you can calculate where to move the engine to.

Keep on ind when you relocate the engine, you "may" want to relocate the rudders assuming they are in the optimal position to begin with. Since its a mild HP setup, that may make less difference than it might on bigger hp. Just something to keep in mind.
I think I need to hire a young secretary to do my typing and thinking for me.
facing the rear of the boat when you are outside of it my prop turns clockwise, most others turn counterclockwise. So having said that I need to put the battery some to the right side.
I am running on a 12'long-6'-6" wide bottom with 17" sides.so I should be ok anyway.
It looks real far back and kinda high. Any better close up picks?
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Re: tork roll

Post by dick2256 »

DDPWRD wrote:
dick2256 wrote:
Whitebear wrote:Right, Corvair is either 4 or 6 cylinder opposed. With torque roll to the CW direction since you said it turns CCW, then put your battery to the CCW side. You can drop the engine quite a bit if you can find a 3 or 4 blade prop for it. If you are going to re-prop the boat, I would get the prop selected before you relocate the engine so you can calculate where to move the engine to.

Keep on ind when you relocate the engine, you "may" want to relocate the rudders assuming they are in the optimal position to begin with. Since its a mild HP setup, that may make less difference than it might on bigger hp. Just something to keep in mind.
I think I need to hire a young secretary to do my typing and thinking for me.
facing the rear of the boat when you are outside of it my prop turns clockwise, most others turn counterclockwise. So having said that I need to put the battery some to the right side.
I am running on a 12'long-6'-6" wide bottom with 17" sides.so I should be ok anyway.
It looks real far back and kinda high. Any better close up picks?
will try to find a better picture
the prop is a beer can length from the back of the boat and top of the motor is 56"s from the bottom of the boat.

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Re: tork roll

Post by dick2256 »

not much help but maybe a better picture of my setup
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Re: tork roll

Post by dodobird »

is that ur exhaust at ur neck? or back
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Re: tork roll

Post by dick2256 »

dick2256 wrote:not much help but maybe a better picture of my setup
yes that is the exhaust but it isn't near as close to the driver as it looks and that is all change since
that picture it has a stock muffler on it now

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Re: tork roll

Post by dick2256 »

try this picture it should be a lot clearer
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Re: tork roll

Post by JAMES »

dick2256 wrote:try this picture it should be a lot clearer
one hell of a lift kit on it :lol:
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Re: tork roll

Post by dick2256 »

JAMES wrote:
dick2256 wrote:try this picture it should be a lot clearer
one hell of a lift kit on it :lol:
that was banks/maxwell plan back in the 70s James not really that bad on a 5' or wider boat

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Re: tork roll

Post by air-roberts »

it looks like to me from pic that the prop turns to r c/w so the right side of boat should torq up so put your weight on right side (when telling r or l of vessel picture being it in back looking forward sitting in seat you rudder stick is in the left stand in back of boat and see which way prop turns etc)
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Re: tork roll

Post by dick2256 »

air-roberts wrote:it looks like to me from pic that the prop turns to r c/w so the right side of boat should torq up so put your weight on right side (when telling r or l of vessel picture being it in back looking forward sitting in seat you rudder stick is in the left stand in back of boat and see which way prop turns etc)
that is correct several years ago I submarined it twice when running on a 44" bottom boat
and both times the right side came up and the left side went under and took the water

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:)
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Re: tork roll

Post by :) »

Is that a reduction unit on the back of the motor? The blue thing?
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Re: tork roll

Post by dick2256 »

:) wrote:Is that a reduction unit on the back of the motor? The blue thing?
I think what you are looking is a waterproof prop cover

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