Body Drop/Fitting Question

[Roger D.]

Folks:

The full restoration of my '72 small block coupe is coming closer to completion. We dropped the body onto the chassis on Sunday afternoon and we feel like the shims are correctly placed. We have not yet tightened any of the body mounting bolts.

Question for anyone who has experience in doing this task: The doors fit perfectly prior to setting the body on the chassis (i.e., while on the body dolly. After sitting the body down on the chassis, the passenger side door still has the same gap spacing between itself and the body at the front, however, the gap spacing between the door and the body at the rear has narrowed more than my liking.
Is it possible that the gaps will adjust themselves once the body bolts are tightened down ? Or is it more likely there is a shim thickness issue? From our measurements the body sits perfectly straight on the chassis just sitting there on top of it.

Any thoughts?

Thanks in advance!

Regards,
Roger

[Richard M.]

Re: Body Drop/Fitting Question

Roger,

Have major changes occurred to the chassis and/or body and did you record original shim counts at each mount location? If you acquired the car all apart and had no shim count data, typically it's then all trial and error, but I usually start with 2 to 3 shims per mount as a starting point.

Either way, I would tighten all of them first before any shim changes. This will give you a better idea of final gaps and may worsen both doors gaps or it may correct some unsatisfactory gaps.

If your Pass side rear gap is still tight, I would remove shim(s) at the #4 mount, if enough are there to remove. If not you may have to add shim(s) at the #3 mount as well as the #2 mount.

Whenever I do this I put masking tape at door edges and body openings where I think rubbing may occur. Also carefully watch the door ends where they get close to the latch pillar and latch assemblies. Often times when things are too tight paint can get scratched in hard to see places.

Rich

[Patrick H.]

Re: Body Drop/Fitting Question

Was body work done with the car fitted to the frame, or fitted to the body dolly? If the body dolly, then because the frame and dolly are not the same you end up with a different fitting (twist), and get the issue you note with door gaps.

AssUming you counted shims initially and the door gaps are different now, it may improve when you tighten it down. But, don't be afraid to use shims to get it right, as there were days the factory did not.

[Roger D.]

Re: Body Drop/Fitting Question

Roger,

Have major changes occurred to the chassis and/or body and did you record original shim counts at each mount location? If you acquired the car all apart and had no shim count data, typically it's then all trial and error, but I usually start with 2 to 3 shims per mount as a starting point.

Either way, I would tighten all of them first before any shim changes. This will give you a better idea of final gaps and may worsen both doors gaps or it may correct some unsatisfactory gaps.

If your Pass side rear gap is still tight, I would remove shim(s) at the #4 mount, if enough are there to remove. If not you may have to add shim(s) at the #3 mount as well as the #2 mount.

Whenever I do this I put masking tape at door edges and body openings where I think rubbing may occur. Also carefully watch the door ends where they get close to the latch pillar and latch assemblies. Often times when things are too tight paint can get scratched in hard to see places.

Rich

Hi Rich:

The original shims were disintegrated due to rust so it was not possible to measure them. On the shim changes you mention I assume that you are talking about the shims on the passenger side right?

I figured before we tackled it again this coming weekend, that I'd try to get some ideas first. I figured the first step would be to tighten down what we have and see if anything changes.

Is it wrong to assume that since the body appears to be sitting perfectly straight on the chassis at moment that the shims we placed are theoretically correct?

Thanks for your thoughts and help.

Regards,
Roger

[Roger D.]

Re: Body Drop/Fitting Question

Was body work done with the car fitted to the frame, or fitted to the body dolly? If the body dolly, then because the frame and dolly are not the same you end up with a different fitting (twist), and get the issue you note with door gaps.

AssUming you counted shims initially and the door gaps are different now, it may improve when you tighten it down. But, don't be afraid to use shims to get it right, as there were days the factory did not.

Hello Patrick:

Yes, everything was done separately with the body on the dolly. However the body only required the usual cosmetic fixes like stress cracks fixed and other minor fiberglass cracks here and there. As I mentioned to Rich, the shims were pretty much rusted away so there was no measuring them during disassembly. Hopefully tightening the body bolts will improve the situation.

Regards,
Roger

[Richard R.]

Re: Body Drop/Fitting Question

Roger,

I dropped the body on my 69 convertible earlier this year. I fiddled with the shims while on a lift with the wheels off and had the doors perfect, but then put the wheels on it and dropped it on the ground and it changed enough to go back to my initial settings which were what it was when I took it apart. I ended up changing shims about 6 times until it was right. made the final adjustments with the door hinges to even out the gaps and keep it within spec. Each time I tightened the body mounts before assessing what to do next. it makes a difference. I did it enough times that I got pretty good at it, along with help from my buddy to do the lifting. We used blocks of wood and a bar to get enough leverage to raise the body off of the frame while I adjusted the shims.
And certainly as Rich M says, protect the edges from rubs.

Rich

[Richard M.]

Re: Body Drop/Fitting Question

Roger, As mentioned, trial and error prevails and things change during tightening. Rich R's note about the weight on the wheels is a very important one also, as even a coupe can move a bit.

One thing I've done at the #3 mounts when adding shims. I've slotted them for ease of installation.

Rich

[Patrick H.]

Re: Body Drop/Fitting Question

As I mentioned to Rich, the shims were pretty much rusted away so there was no measuring them during disassembly. Hopefully tightening the body bolts will improve the situation.

Regards,
Roger

Roger,

The best technique at that point is to put the body right back on the frame and use new shims to get it right before you start the body work. But, too late for that.

As has been said, you will probably have to do some trial-and-error with shims to get it to fit correctly. Just be mentally prepared for some body up-and-down.

[Roger D.]

Re: Body Drop/Fitting Question

Thanks everyone for the suggestions. Will be getting back to the task in about an hour. One thing I'm missing though is what clues tell you what shim changes to make? Is it all just a guessing game or is there a rhyme or reason as to what shim adjustment goes where?

Regards,
Roger

[Patrick H.]

Re: Body Drop/Fitting Question

Thanks everyone for the suggestions. Will be getting back to the task in about an hour. One thing I'm missing though is what clues tell you what shim changes to make? Is it all just a guessing game or is there a rhyme or reason as to what shim adjustment goes where?

Regards,
Roger

Use the gaps as a way to figure out how many to put where. As you tighten it the first time, see if gaps get bigger or smaller, and tightening bolt X makes gap Y expand, that type of thing.

[Roger D.]

Re: Body Drop/Fitting Question

Use the gaps as a way to figure out how many to put where. As you tighten it the first time, see if gaps get bigger or smaller, and tightening bolt X makes gap Y expand, that type of thing.

Thanks Patrick. Will let ya'll know how it comes out. Heading over to the garage now.....

Roger

[Roger D.]

Re: Body Drop/Fitting Question

Folks:

After a long weekend (and your right Patrick... a lot of body up, body down, body up, etc. ) the chassis is bolted down for the final time and all gaps are perfect! Thanks for everyone's suggestions support! Now just a bunch of detail work remaining to finish. Here's a few pic's of the soon to be complete total restore that you guys have answered soooo many questions on so far. We couldn't have done it without ya'll!

Thanks.

Regards,
Roger

[Eric E.]

Re: Body Drop/Fitting Question

Looks great. Nice work.
its amazes me the steps that go into a good body drop when the original assembly was so fast.

[Roger D.]

Re: Body Drop/Fitting Question

Looks great. Nice work.
its amazes me the steps that go into a good body drop when the original assembly was so fast.

Hi Eric, thanks for the kind words. It's been a long time coming. Started the restore 4 years ago this August and worked until my wife got sick in 2015. I missed that whole year taking care of her. Picked back up on it after she passed in December '15. After that we (my brother and I) worked on it nearly weekend up to now. Hopefully, it will be completed in a month or so.

Regards,
Roger

[Eric E.]

Re: Body Drop/Fitting Question

Sorry to read of your loss Roger. Sounds like your 72 was a good focus for you when many cant find themselves. A lot of labor of love.