Which comes first: Straightening the tub or structural rust repair? Options

[doug_b_928]

I've been disassembling my car and getting a better sense of what happened to it before my ownership. I think the car was hit on the left rear corner. It doesn't appear that it crumpled much at all. In fact, the left taillight assembly was re-used (the black plastic on the end is missing a 1 cm piece and there's a crack in the middle of the black plastic on the back). There's also a really bad bondo repair about the diameter of an average hand by the tailight. So I don't think much crumple-type of damage was done. But, that hit must have somehow twisted the chassis by either pushing the left rear down and/or pushing the right rear up. There is a big difference in height left to right when looking at the rear end (like 1 -1.5"). The suspension ear on the right is 4mm higher than the one on the left. The latter might even be within factory spec, no? Also, the distance between the trunk channels on the rear fenders is within spec for the front half, but the back half progressively narrows to being 1.5cm too narrow.

The longs, rockers, firewall and hell hole are shot and the door gaps by the door handles are too big (8-9mm). So, I'm wondering, (aside from the option of scrapping it), do I get the chassis straightened before metal surgery, or after surgery on the main structural parts? I could see the former tearing the car apart, and the latter creating imperfections in the newly repaired work.

[doug_b_928]

Thanks, SirAndy. I guess if the chassis is held on a frame bench by the pinch welds it probably won't pull apart. As promised, here are the pics to help with diagnosis:

Here is the back view of the car. The floor is sloped so look at the car relative to the bench. The difference is fairly dramatic.



The car sustained damage on the left rear corner. Here's a pic of the bad bondo repair:



But the damage appears not to have been too bad in terms of crumpling. Here's a pic of the left rear corner:



Here's the left rear from underneath (note that the bracket is no longer welded to the fender, but does not appear to have been crumpled).



Here's what appears to have been a patch put in the left rear corner.



Although the back view looks like it's about 1.5" out left to right, and they had nearly twice as many suspension shims on the right than the left side, from the trunk crossmember to the firewall the car seems to be out only about 1/4" (higher on the right side). At the firewall it's less than 1/4", but at the suspension ears it's about 1/4". I have the car resting on bars on the bench, in the pics below you can see that it's resting on the bar on the left side and it is not quite resting on the bar on the right side.





I have two supports for the rear section and have it set a bit higher on the right than the left to try to support it, so I'm not sure how much that is affecting the measurements, if at all. When I had the supports set higher to try to close the door gaps, the gaps did close at the top of the door/rear fender, but the firewall was even further away from the bar. I wasn't comfortable with that so I lowered the supports, which opens up the door gaps 2mm wider than without the support.

You're probably thinking that the f measurement (windshield flange to targa bar is too big. According to my measurements, if anything they're a bit too small (633mm on the left and 635mm on the right compared to a spec of 638mm). Below are some pics of this measurement. The first one is showing the left side so the measurement is to the targa bar:



The second pic is of the right side so the measurement is to the windshield flange (unless I'm measuring this wrong--please have a look and see if I'm understanding the "flange" correctly.



So, if I'm measuring correctly, that appears to be good (and the roof lines up and works as it should). But here are the door gaps:



















So, bearing in mind my lack of education in this realm, it seems to me that the right rear needs to be pulled down 1/4". The very back piece (after the trunk crossmember) even more. But it still doesn't make sense to me what is happening with the door gaps. At the fronts they look pretty good, same for top front. But by the door handles they're way too big. It's also interesting that the fenders are wider than the doors. I've assumed that's some kind of shim setting with the doors because it's the same on both sides, but please let me know if it means something more nefarious.

Thoughts?

[SirAndy]

Thoughts?

Here:
http://www.914world.com/bbs2/index.php?showtopic=52631

And more pix here:
http://www.914world.com/bbs2/index.php?showtopic=92489

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