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Discussion Starter #1
In terms of a sprung over rear end I have been reading up on this, alot of people have posted this about the "Sams Offroad design" bar. I guess I dont understand how this can be true with a bar that does not position the axle. Especially with the shackle at the top.... How can it lift the rear of the vehicle without having a solid mount at the frame side. Can someone please explain this, my feeble mind does not comprehend it. Thanks,

Ryan
 

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yes, it causes anti-squat. The tip of the A-shaped bar tries to move vertically when the axle tries to rotate. Think about the lobes on a camshaft - they convert rotation into lift, and a traction bar does the same thing. Then the shackle at the frame tries to lift up on the frame mount. Wherever you mount the shackle to the frame is your IC. Depending on how soft your springs are, the traction bar has more/less efect on AS value...
 

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The anti-wrap bar converts the rotation of the axle housing into a vertical force at the shackle end. Housing trying to rotate clockwise (looking at the driver's side rear tire) translates into an upward force at the shackle/crossmember end of the bar. This upward force at the shackle end has an equal and opposite reactive force that will force the tires downward, producing anti-squat.

Clear as mud?
 

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Discussion Starter #4
they convert rotation into lift, and a traction bar does the same thing. Then the shackle at the frame tries to lift up on the frame mount.

I understand this. Thank you. Now could I use this to my advantage by moving the Instant Center where I want it to be so the rear wouldnt squat under hard accel as badly? I guess I can play with the numbers but I dont want a 200% AS or something.

I guess I am asking because I was all ready to make one of these and I searched for some info/ideas on what to look out for, and found quite a few people didnt like the design. Just trying to figure out why. also found something called a "Bam Bar" on Jeeps anonymous, seems easy enough to make, but I dont want to weld to the diff. Any thoughts?

Ryan
 

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Well, I run a center limit strap with mine, and it climbs better now than before. Alot of the comp buggies have high AS and a tight center strap;) As far as being able to adjust it, I dont know that it really can be adjustable without completely rebuilding it, then I dont know ho much good it would do.
 

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As a general rule, the longer the traction bar the better it will behave.

IMO, this is one of those "don't overthink it" times. Make it long, relatively level, and as close to the center of the vehicle as you can. If not centered, passenger side is preferable to driver's side.

You'll be happy with the end result.
 

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The Bam Bar is a single bar setup and therefore does not provide any AS. Stay with the ladder bar if you are trying to gain some AS.
 

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Discussion Starter #8
Thanks I Lean.


One more idea,

Assuming I am using Spherical bearings as my flexing mount, should I make it with 3, or with two bushings at the axle and one bearing at the top of the shackle, I want to make sure it flexes enough.


Also....
BadAZYj Well, I run a center limit strap with mine, and it climbs better now than before.
you run a strap on a spring over? cool, I am thinking of doing it on my four link.. And you like how that works with the leafs huh?
I like that idea. Got any pics BadAZYj?

Thanks,

Ryan
 

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Yeah, I run a strap with a spring over and anti wrap bar. Im preety happy with it, but I plan on 4 linking and COing the rear soon. Heres a pic of my rig on Annihilator a couple weeks ago, it was muddy and required a few "bumps" but I did make it up unassisted:D If you really want Ill go take a picture of the strap, Im not sure what your asking for though.
 

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YeeP said:
Thanks I Lean.


One more idea,

Assuming I am using Spherical bearings as my flexing mount, should I make it with 3, or with two bushings at the axle and one bearing at the top of the shackle, I want to make sure it flexes enough.

I like using bushings at both the axle points, personally. However, if you use rod ends at the axle, it allows for easier adjustability later on. I make one of the bushings adjustable, to get the best of both worlds. :D
 

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Discussion Starter #11
BadAZyj- how what kind of set are you runing with the joint ends? I am thinking two leaf bushings at the axle end and a spherical bearings at the top of the shackle, with another bushing at the bottom. Im a little worried about this not being able to rotate enough. Any thoughts?

Ryan
 

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Well, Im running a 3/4 heim at the frame end, and boulder bushings at the axle end. So I have all sorts of adjustability.
 
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