Another thing which was a recurring problem was that the camber kept slipping out of adjustment. I would adjust the alignment, lock everything down as best as I could, and then after I drove the car a little bit, I'd look at the car in a parking lot, for example, and it would look like I could tell that the camber was excessive and the toe was out. I'd check the alignment, and sure enough, things had slipped. I thought I must not be getting the nuts on the camber bolts tight enough after adjusting it, or I wondered if the powdercoat on the frame didn't provide enough friction to keep the bolts from slipping, or I don't know what.
The worst part of all of this was that sometimes things would loosen up to the point where catching a bump in the road in a certain way would put the whole steering linkage into a "death wobble." The steering wheel would shake violently, and the only way to get it to stop would be to slow the car down to nearly a stop. This probably only happened five or six times, but if it happens even once, it doesn't feel trivial in the moment.
Anyway, after many repetitions of adjustment and trial and error, I think I finally figured out that the problem was the reproduction camber bolts I used when I put everything together.
The camber bolt is a large bolt that passes through the inboard pivot point of the lower control arm. The bolt also passes through two large washers, but it's off-center in the washers. The washers can't spin on the bolt, so if the bolt turns, the washers turn with it. The picture below shows a camber bolt with its washers on it.
The bolt installs through slotted holes in the frame, and the washers sit between rails on the frame. Because the washers are constrained between those rails, and because the washers can't spin on the bolt, the result is that rotating the bolt and washers together causes the bolt to slide inboard or outboard in the slot in the frame. The pictures below show a cartoon of the assembly, looking from the front of the car towards the rear. The rails and the slot in the frame are represented in green, the washers and camber bolt are represented in red, and the lower control arm is represented in blue.
The three cases here show the bolt centered in the slot (top), rotated to move to the outboard side of the slot (center), and rotated to move to the inboard side of the slot (bottom). These three cases result in zero camber (top), negative camber (center), and positive camber (bottom).
That's how the assembly is supposed to work, and the camber bolt in the first picture is how the bolt is supposed to look. But when I was putting everything together, I wanted to replace the original camber bolts with new ones. One of the washers on one of the original bolts, which was supposed to be welded in place, had broken loose and would spin on the bolt. Also, I was just replacing most of the hardware on the car, anyway, so I don't know, it seemed like a good idea. But, I had trouble finding reproduction camber bolts. Nobody seemed to have them. I finally found one auto parts store that had them listed in their system, but they were backordered. It took months for them to show up, and it felt like I got the last pair of bolts in their whole inventory system, maybe the last pair on Earth.
When they arrived, I could see that they were different in form from the originals, but they looked like they should be equivalent in function. They looked like the bolt shown in the photo below.
The original bolts are round for most of their length, with an offset washer welded to the end with the head of the bolt. They have a flat at the free end of the bolt, and the loose washer is clocked by that flat, which keeps it from spinning on the bolt. You can see in the photo above, though, that on these reproductions the flat runs the full length of the bolt. Neither washer is welded to the bolt, and both washers are clocked by the flat. I'm sure this allows a reduction in cost because you can make twice as many of one washer design, instead of half as many of each of two different washer designs, and also because you eliminate the need for the welding operation. Like I said, I could see by looking at it that it was different, but I thought it looked like it should be functionally identical.
But, after going around and around with adjusting the alignment and having it slip back out of alignment, I decided I wanted to replace these bolts. I had tried everything I could think of (short of tack welds) to keep them from slipping, and nothing had worked. I wanted to just get some original bolts to put in there. I had one bolt with a broken weld, and I had lost one of the nuts somewhere along the way, so I didn't want to use the originals that were on the car when I got it. I wondered if someone might be selling a pair of original camber bolts on ebay. But when I checked, I actually found someone selling brand new reproductions that match the design of the original bolts. I was kind of skeptical about them, for a variety of reasons. They were being sold by some company I'd never heard of, and when I went to that company's website, they didn't list camber bolts among the products they were selling. But, it seemed like a better option than anything else I had, so I decided to order a pair.
Long story short, I think they fixed my problem. When I tried to remove the bad bolts, the nuts seized up on them and I had to cut them off with a cut-off wheel. One last inconvenience from these pieces of junk. But, I got them out, got the new ones in, got everything lined up, torqued down, and I made some paint marks so I could easily check if they slipped after that. So far, it seems OK. And now, after the fact, I think I figured out why the first ones I installed don't work.
If you look at a cross section of the portion of the bolt that's in the slot in the frame, the original design is round, and any reaction forces from the frame pass through the center of the bolt (at left in the picture below). With the design that has the flats running the full length of the bolt, there are flats in the slot, and the reaction forces from the frame are not through the center of the bolt. In fact, they exert a moment on the bolt, trying to twist it (at right in the picture below).
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