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So I just installed these UMI Adjustable rear upper control arms and forgot to check which direction extends or retracts while they were on the bench. If I'm laying on my back under the car looking up with my feet at the bumper , which way do I turn the turnbuckle to extend the control arm to add length ???? ..Any help is appreciated.
 

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You are going to have to pull them back off then take one side and adjust it to match the factory control arm. Then install just that one and dial in your pinion angle from there and then make the other one match, after that you are going to know what to do with them.
 

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I adjusted them to match the stock which are approximately 10.25 inches while on the bench prior to install. I just wanted to get an idea of which way to turn them to retract (make shorter). Just trying to simplify adjusting them.
 

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It's going to simplify adjusting them by taking the other one off. Pull the other one and adjust the single one to get the pinon angle right, then all you have to do is make the other one match and put it on. If you really want to try to dial in 2 adjustable uppers and the same time it's going to suck cause one will always be fighting the other and will give weird end results. What are you aiming to change here being that you already have them set to the stock positions? What is it that you want to change?
 

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Did Instructions come with them ?

Looking at the pics of them I would think that that the End Attached to the Rearend Housing Upper Ears
is where you Lengthen or Shorten them
and since that is where they are Longest plus there is a Nut Welded onto that part of the Arm

I would suggest you call/Email Ramey at UMI Perf for advise !
 
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I posted in your other thread. Hopefully one of the mods will combine the threads.

So I just installed these UMI Adjustable rear upper control arms and forgot to check which direction extends or retracts while they were on the bench. If I'm laying on my back under the car looking up with my feet at the bumper , which way do I turn the turnbuckle to extend the control arm to add length ???? ..Any help is appreciated.
 

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They are a normal turnbuckle - one end has left hand threads, the other has right hand threads.

You loosen the lock nuts, then turn the turnbuckle. It causes the whole arm to get longer or shorter. You then tighten up the lock nuts again.

Did Instructions come with them ?

Looking at the pics of them I would think that that the End Attached to the Rearend Housing Upper Ears
is where you Lengthen or Shorten them
and since that is where they are Longest plus there is a Nut Welded onto that part of the Arm

I would suggest you call/Email Ramey at UMI Perf for advise !
 

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I installed these on my car. Rame is probably right by installing one and then getting your pinion angle. Not knowing this, I installed both and they did fight each other but eventually I got it dialed in.

I just measured at the threads and seen which way they adjusted. you know, trial and error. Wasn't that tough to figure out.

Steve is correct, left and right hand threads.
 

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I installed these on my car. Rame is probably right by installing one and then getting your pinion angle. Not knowing this, I installed both and they did fight each other but eventually I got it dialed in.

I just measured at the threads and seen which way they adjusted. you know, trial and error. Wasn't that tough to figure out.

Steve is correct, left and right hand threads.
I also learned this trick after the fact, I had the same problem myself. Did you check the center? Because you should. You can put the rear in a bind either left or right and cause premature tire wear, or it can keep the bushings in a bind and cause premature failure on them too (I think the car would crab walk it you had it that bad though). Unless it's extreme it will take a while before you notice so it's worth checking when changing anything from stock.
 

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You can't just put one upper arm in and leave the other out and adjust the pinion angle and then put the other in. Not only will it move the pinion angle up and down, it will move the rear end from side to side without the other one installed and you'll wind up off center. And when you put the other arm in, you'll get back to center if you use the same length, but the pumpkin may move up/down as well which will change the pinion angle and you'll have to start over.

You actually do want the uppers to push against each other - that will help center the rear end and simply move the top of the pumpkin backwards and forwards. With only one upper arm installed, it will move side to side as well without the other arm to keep it centered.

The easy button is that when you install them, make sure they are both the same length. Actual length doesn't really matter, but starting with factory length on each is easiest. Then just check to make sure your rear end is centered (it should be pretty close if nothing else is bent/off.) If the rear end is not centered, you lengthen one and shorten the other to get it centered (and if it goes more off center, shorten the one you just lengthened and lengthen the one you just shortened.) You should not have to do much of this to get it centered. Measure from the frame, not the body, because the body may not be centered on the frame.

Once you get the rear end centered, you can then adjust the pinion angle by lengthening or shortening both arms by the same number of turns in or out. That should keep the rear centered, but it is best to check center again once you get the pinion angle you want just to make sure.
 

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You can't just put one upper arm in and leave the other out and adjust the pinion angle and then put the other in. Not only will it move the pinion angle up and down, it will move the rear end from side to side without the other one installed and you'll wind up off center. And when you put the other arm in, you'll get back to center if you use the same length, but the pumpkin may move up/down as well which will change the pinion angle and you'll have to start over.

You actually do want the uppers to push against each other - that will help center the rear end and simply move the top of the pumpkin backwards and forwards. With only one upper arm installed, it will move side to side as well without the other arm to keep it centered.

The easy button is that when you install them, make sure they are both the same length. Actual length doesn't really matter, but starting with factory length on each is easiest. Then just check to make sure your rear end is centered (it should be pretty close if nothing else is bent/off.) If the rear end is not centered, you lengthen one and shorten the other to get it centered (and if it goes more off center, shorten the one you just lengthened and lengthen the one you just shortened.) You should not have to do much of this to get it centered. Measure from the frame, not the body, because the body may not be centered on the frame.

Once you get the rear end centered, you can then adjust the pinion angle by lengthening or shortening both arms by the same number of turns in or out. That should keep the rear centered, but it is best to check center again once you get the pinion angle you want just to make sure.
I guess I probably did it correctly then. I remember measuring the crap out of everything making sure the diff was centered and square with the frame. And I did follow the UMI instructions.

The one thing I had to do was to make sure the driveshaft fit back in to the differential yoke correctly. My bushings and factory control arms were so beat and used up, I actually had to pry the driveshaft out before I dropped the rear end out.
 
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