Chevy Tri Five Forum banner

1 - 8 of 8 Posts

·
Registered
Joined
·
238 Posts
Discussion Starter #1
Hi
I am putting a full floor in my 55 hardtop, my question is can I mount the floor to the frame without shims and then line the body up around the floor or will that cause issues later on? I am doing the main floor from the firewall up to the rear seat first and then will do the trunk. I am also doing outer rockers and rear quarters.
Thanks
 

·
Registered
Joined
·
1,396 Posts
There are many here who have more experience with this than I, but no one else has chimed in yet so I'll take a stab based on the one time I did it: I fully mounted the floor to the frame first (tightened all of the bolts completely) with no shims, then let the body down on to the floor and welded together This establishes the floor-to-body relationship with no shims in the equation. Since the factory completed the bodies separate and prior to being set on to the frame, shims were/are necessary to make things fit 'perfectly' given slight differences that might exist between the two. Since a separate floor pan is 'floppy' enough to conform to the frame, you can bolt down without any shims, and after you get the body welded to it - you will have effectively eliminated the need for the them.
JR
 

·
Administrator
Joined
·
64,002 Posts
Set the replacement floor, get that right and weld into position. Then complete the rear half. Continue with completing the inner/outer rockers.
Place the body back onto frame, fit doors and check to see if shims are require to make any adjustments to gaps.
 

·
Registered
Joined
·
238 Posts
Discussion Starter #4
Thanks guys
It seems to sit in there pretty well but I put bracing in the way of fitting up the doors. I will tack it in there and then remove enough bracing to fit the doors and check gaps. Amateur at this type of work so I am taking my time. About 12 years to get to this stage so far.
 

·
Registered
Joined
·
98 Posts
Year late on this but maybe it will help someone. Roll frame out and check support brackets against the frame drawing in the GM assembly manual. I used a tripod level. About half of the supports were at the right height. A couple of my support brackets were 1/4" too high and the rear of my frame had drooped 3/16". The factory had just beat the high supports down with a hammer. I cut them loose and relocated them to the correct height. Then I determined where shims were required. After you get the supports/shims situation straightened out you can use the frame as an assembly jig for the body parts. If the support brackets aren't right I don't know how that will end up. Even if you are replacing the entire floor you would be better off with a level foundation. I think that what I am trying to state is that you can't count on the factory to have gotten it right. Quality, apparently, had not been invented yet. I've wondered if the better made frames went to the Bel Airs and the poorer quality frames were mated to 210's and 150's.
 

·
Registered
Joined
·
36,013 Posts
If I were to attempt this job, I'd set the new floor on the frame with no shims and note where any high spots or gaps were. Then I'd shim to match. If there were extremes then I'd look into whether they come from the frame or the floor. Fixing the location of one or two of the frame supports is pretty easy.

There's nothing to say the floor wouldn't be the problem rather than the frame.

I don't think it's fair to say "quality hadn't been invented yet". Rather, the cost of precision welding exceeded the cost goals. It was an economic decision.
 

·
Registered
Joined
·
238 Posts
Discussion Starter #7
A bit of an old thread but still not too late. I have been a little busy on other things since I first asked my question. I have the floor tacked in and have been working on fitting golden star quarters along with their issues. I have been considering at least taking the body back off and rechecking the frame before I go any further. There are discrepancies in the line up of panels from driver to passenger side which I think may be caused by this. I originally taped all my shims to a piece cardboard and had them all in order but they all fell off and that was that. Rightly or wrongly I just fitted the floor to the chassis without shims.
One day I will get there.
01D1817E-465F-4F90-A81F-4CCCB6F28A3F.png
 
1 - 8 of 8 Posts
Top