To access shims in rear control arm, not an option if you are aligning one of these cars, the bolts that hold the arm in are invariably hopelessly frozen. This was not a good set up from the beginning. When Chevy went to this setup in 63 it was possibly understandable. But they stayed with it for nearly 20 years. Lots of these cars on the road and lots of enthusiasts want them properly aligned. Few can do it and few of them are willing to put in the work. We don't mind putting in the work, we like to do things right. You just have to be willing to pay for the required time. If someone your looking at to align your car says we can't do the rear, we can't get the shims or whatever, what they are saying is we can't align your car.
The control arm on the bench. To get it to this point took 4 hrs. The bolt is frozen so tightly to the inner sleeve of the bushing they won't budge. We remove the shims from the outside, cut the bolt with a sawzall, cut the head off the other end and twist the arm out. Once out the bolt and bushing can be beaten or pressed out.
New bushing pressed in and seated with special tool. I don't know how you could do this properly without tool.
Here are what the variable thickness shims look like before they are installed.
Here are the shims installed during the alignment. (Note: We re-used a few old shims and added some new ones in order to get the toe in spec)
Here is the original alignment on the car before we adjusted anything. The top box is how the car was before adjustments. The bottom box is the car after adjustments. Notice the right rear camber is very positive in the top box. This was done by a previous technician in order to get the toe as close as possible. He sacrified camber for toe in order to get the car to drive better. The camber was so positive, you could visibly see the wheel leaning out at the top. If you notice the bottom right corner of the sheet, you can see that we set camber to spec, and that toe is no where close to where it should be after camber adjustments. Shims need to be moved in order to set toe properly. Descison was made after customer approval to cut the bolt out and replace the bushing in order to move shims. The arm and bushing was frozen to the bolt, not allowing movement of shims.
Here is the final alignment sheet of the car. Shims were properly installed in the rear in order to set toe once camber was set. We also aligned the front end. All measurements are now in spec. The car now drives like it should, and will no longer have any premature tire wear.
Finished product. One happy Corvette and One happy customer!
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