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help on centering the rear?

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Old Mar 2, 2011 | 09:03 PM
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Default help on centering the rear?

I just recently did some suspension mods and added new wheels to the car. These are the mods...

UMI Adjustable Lower Control Arms
UMI Subframe Connectors (bolt in)

I have a UMI Adjustable Panhard Bar. Dont remember the exact part# but its 1 of these just like the one in the link....
http://www.umiperformance.com/catalo...kpbqs5270tdtl1

After installing the LCA's & SFC's, the rear doesnt look centered at all. Now yea, im going by visual appearance not actuall measurements but even visually. You can tell that the passengerside is further in the wheel well then the driverside. Ive tried adjusting it with the panhard bar but im honestly only seeing the driverside wheel move in/out when im doing that. Im not seeing any movement from the passengerside. Idk why i started with the passengerside LCA/SFC install but i did. It wasnt till i read the directions that told me to start with the driverside. If i removed the LCA on the driverside, would it help shift the rear to the passengerside and helping it move more outward?

Would this affect ride quality? I feel like my rides gotten worse, and feels like its coming from the passengerside. Like it takes bumps worse then the driverside. Also hearing a knocking noise but thats probably due to the bolts loosening up a little. Im going to add some locktite to the bolts this coming weekend and work on getting the rear more centered.

How do i go about fixing this issue, without going to a shop for an alignment?

I wanna do other suspension mods 1st before i do that. I dont want to go for an alignment now and then go again later because i added more suspension mods.
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Old Mar 3, 2011 | 06:52 AM
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Hello,

When you installed the lower control arms did you make sure they were set to factory length? We preset them here during assembly however they can move during shipping a little or sometimes customers like to screw them in and out and play with them

The rear ends do not sit centered from the factory so if your control arms are set to factory length the rear end would be in the same place as you started. Starting on the passenger side rather than drivers won't matter. But since you have adjustable control arms you can center the rear end, take your measurements from a frame spot and not the rear bumper or fender.

As for the noise, when you install the SFC's it will take a lot for torque to tighten the front control arm bolt since the SFC wraps around it. Because of this design you need to compress the SFC mount and control arm mount before it tightens against the bushing. Tighten the front control arm bolts extra tight and your clunking noise should be gone.

I hope that helps,
Ryan
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Old Mar 3, 2011 | 06:58 AM
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any good alignment shop should be able to adjust it all.
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Old Mar 3, 2011 | 07:05 AM
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The rear is one solid piece. If your adjusting the panhard it should move the whole thing. Have the rear hanging in the air and then adjust it. set the car down and see how it looks. It doesnt make sense at all why your only seeing the one side move in or out.
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Old Mar 3, 2011 | 07:10 AM
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Originally Posted by Badazz 97 TA
.... It doesnt make sense at all why your only seeing the one side move in or out.

Not only doesn't it make sense, it's physically impossible. You lengthen/shorten the PHB, the entire rear axle assembly moves laterally, with respect to the chassis.
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Old Mar 3, 2011 | 07:43 PM
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Originally Posted by Badazz 97 TA
The rear is one solid piece. If your adjusting the panhard it should move the whole thing. Have the rear hanging in the air and then adjust it. set the car down and see how it looks. It doesnt make sense at all why your only seeing the one side move in or out.
or set the rear on jack stands
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Old Mar 3, 2011 | 08:28 PM
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Originally Posted by UMI Performance
Hello,

When you installed the lower control arms did you make sure they were set to factory length? We preset them here during assembly however they can move during shipping a little or sometimes customers like to screw them in and out and play with them

The rear ends do not sit centered from the factory so if your control arms are set to factory length the rear end would be in the same place as you started. Starting on the passenger side rather than drivers won't matter. But since you have adjustable control arms you can center the rear end, take your measurements from a frame spot and not the rear bumper or fender.

As for the noise, when you install the SFC's it will take a lot for torque to tighten the front control arm bolt since the SFC wraps around it. Because of this design you need to compress the SFC mount and control arm mount before it tightens against the bushing. Tighten the front control arm bolts extra tight and your clunking noise should be gone.

I hope that helps,
Ryan
Thanks for the reply Ryan. I think i may have moved the settings on 1 of the LCA a little because i did have to adjust the passengerside some to line up with the hole for the bolt. I dont remember having to do that on the driverside. I did have other issues on the passenger side as well, the LCA did not fit right in place. The part where LCA goes inside of, i had to bend it out just a little to get the LCA to finally go in there because it wouldnt just slide right in there. Maybe i lifted the car up wrong from there before or the previous owner did. Idk but that was the only issue i had.

Ill go back this weekend and re-tighten everything down. Take the car out for a quick spin, see if the problem continues.
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Old Mar 3, 2011 | 08:29 PM
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And to the other's who posted, i guess maybe im just not seeing it move when it really is.
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Old Mar 4, 2011 | 07:33 AM
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Originally Posted by 19xtreme99
or set the rear on jack stands
what?? obviously you dont want them on the rear itself otherwise its gonna be impossible to shift it were he needs it. Jackstands should be on the frame with the rear hanging.
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Old Mar 4, 2011 | 05:30 PM
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Originally Posted by Badazz 97 TA
what?? obviously you dont want them on the rear itself otherwise its gonna be impossible to shift it were he needs it. Jackstands should be on the frame with the rear hanging.
NO, the rear should NOT be hanging, as the rear moves in an arc as it rises and falls, therefore if it's hanging, you won't get an accurate measurement. The rear CAN be on jackstands, because as you adjust the phb, it will move the body in relation to the axle.
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Old Mar 4, 2011 | 07:49 PM
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Originally Posted by leadfoot4
NO, the rear should NOT be hanging, as the rear moves in an arc as it rises and falls, therefore if it's hanging, you won't get an accurate measurement. The rear CAN be on jackstands, because as you adjust the phb, it will move the body in relation to the axle.
are you assuming its an on car adjustable phb? cuz i know i wouldnt be able to do that with my single adjustable phb. in the end i really dont care
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Old Mar 4, 2011 | 08:20 PM
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^ After looking at my order history from Byunspeed.com. I found out that i ordered my PHB from them and its the "on car adjustable" phb by UMI.
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Old Mar 5, 2011 | 07:00 AM
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Originally Posted by Badazz 97 TA
are you assuming its an on car adjustable phb? cuz i know i wouldnt be able to do that with my single adjustable phb. in the end i really dont care
Either way, the car HAS to have the suspension loaded, whether it be on the ground, a drive-on lift, ramps, jack stands, whatever, in order to get an accurate measurement....
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Old Mar 5, 2011 | 07:41 AM
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well no duh, i didnt say in order to get a measurement. I was just saying how to adjust it in order to get the bolt holes to line up after you make an adjustment. i didnt know if he had a on car or single adjustable phb or not so i assumed the latter. read my first post again.
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Old Mar 5, 2011 | 07:51 AM
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Originally Posted by Badguy7
Thanks for the reply Ryan. I think i may have moved the settings on 1 of the LCA a little because i did have to adjust the passengerside some to line up with the hole for the bolt.
That is most likely your problem. When putting the lower control arms on one will go in fine and the other you'll have to push the rearend to line up the hole. You don't adjust the LCA longer or shorter to accomadate the rearend.
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Old Mar 5, 2011 | 05:23 PM
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^^ Ahh ok, so how do i go about fixing that then?

Remove it, line it up back to stock length (using the stock lca to make the measurement) and push on the rear to get it to line up?
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Old Mar 5, 2011 | 05:56 PM
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i would take them off, make sure each are close to factory measurements and stat over. that way you start with a clean slate..no 1 thats somewhat shorter. i hope it makes sense.
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Old Mar 5, 2011 | 07:49 PM
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^ Yea i get you, i need to put some locktite on the bolts anyways. Ill probably just do the passengerside (as far as removing the lca and adjusting it to stock length) since its the one im hearing the clunk/noise from.

I adjusted the rear, probably not centered exactly but it looks alot better then before. Each side looks to be fairly close, ill do some measurements on it tomorrow to be exact. It got dark on me.
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Old Mar 13, 2011 | 06:09 PM
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Default tape & string

I just taped a piece of string on the quarter panel (centered to the rim) with a washer for weight and jacked up the car till the car just starts to lift, place jack stands under the rear for safty ((barely touching)) rear and adjust the pan bar till it measures even on each side. Easy as **** to do!
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Old Mar 13, 2011 | 08:35 PM
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I used a plumb line against the quarter panel and measured it from the top of the rim. Each side is within a 1/16 of each other.
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