kny3twalker

iTrader: (31)

Well I spent memorial day weekend installing a new moser 12 bolt build by scott at Driveline Solutions. Now the rear is so crooked that when I tried to drive the car, my steering wheel alignment is off by almost 30 degrees. The rear is visually not perpendicular to the car. I have an adjustable panhard bar and adjustable lower control arms, and while I cannot imagine this would cause any issues, I believe I did switch the orientation of the panhard bar when reinstalling it during the build. Currently the rear is set further towards the rear on the passenger side than on the driver's side. Does anyone have any measurements that woudl help me center my rear? Also does anyone know where I should begin to take measurements to line up the rear? Also are there shops which will do rear alignments for modified F-bodies? Any other advice would help as well. And the search is down!

02Z28LS1

iTrader: (2)

haha, just kidding

anyway, (someone please correct me if i'm wrong with any of the below), but all you should need to do is center the wheels in the rear wheel well....measure from the outermost part of the rim itself (not the tire)....take 4 individual measurements......1 on each side from the outermost lip of the rim towards the front of the car to the bottom-most inside edge of the wheel well, then 1 on each side going the other direction, from the outermost edge of the rim (on the other side of the rim from the first measurement) going towards the rear of the car to the bottom-most inside corner of the wheel well.

when both of those measurements are equal on each side (by adjusting the LCA's), the rear end is centered in that direction.

then, once that is done, you will need to also use a drop-line from the highest point of the wheel well, then measure each side from where that line drops to the outermost edge of the rim. when those two sides are equal (by adjusting the PHR), you have a centered rear end.

of course, these measurements may be off a little if there has ever been any body damage in the rear of the car, but if you're currently able to tell that it's not right, just by looking at it, it will still be a hell of a lot better than it is now.

revtime

iTrader: (1)

I just installed my Strange 12 bolt as well.
Here is what I did. I measured my old Lakewood non adjustable LCAs, I came up with 19 inches (if I remember correctly, don't quote me on that) I measured at the edge where the bolts go through the bushing. Now I took my double adjustable rod end LCAs and made them 191/4 inches which moved my rear back 1/4 from where the lakewoods had it.
To better center the rear for the 28 inch tires I want to run.
From your description you need to remove the LCAs and make sure they are both the same length.
The PHR will center the rear side to side, meaning if you have more tire sticking out on the driver side then you need to shorten your PHR to bring the rear more to the passenger side.
The LCAs need to be the same length on each side so the tire will be centered in the wheelwell on both sides.

This of course is assuming nothing has been damaged.

kny3twalker

iTrader: (31)

Are you sure it is completely necessary for them to be the same length cause with the 10 bolt in the car, the rear was straight. Now that I have installed the 12 bolt the rear is crooked, but I suppose it is possible that the LCAs were tempered with during the install.

The only damage to the rear of the car is those "torque dimples" that our cars get in the arch at the wheel well.

DuronClocker

iTrader: (25)

Does it look like the LCA mounting points on the rear itself are lined up with each other? Maybe they were welded wrong from the factory.

kny3twalker

iTrader: (31)

What would be the best method to go about checking whether they are straight (parallel to each other)? And what can I do if Moser welded the LCA bracket incorrectly? I do know that the LCA mount on the passenger side was slightly wider than the mount on the drivers side, and it difficult to get the emergency brake bracket over the back side of the mount.
I will be spending Saturday trying to tweak the suspension. I will check all of these possible issues.

Irocss85

iTrader: (1)

well you shouldnt have to make them unequal length. and, you cant just eyeball if there centered frt/back by looking at the wheel wells. I heard from a guy that put on 28" tires thathe figured out the wheel wells are not exactly the same on both sides. I would start with measureing the lengths to see if there the same side to side. if they are, and the rear is crooked, then you could try to get a 4 wheel alignment and make them unequal lengths to try and get the rear square. if its very different, or cant get it to line up right at all, then Id be calling moser to see what they'll do.