Body mount shims 1971

[Vincent F.]

This idiot I bought my car from put rubber body mounts on,so obviously I installed the correct alluminum mounts.not happy with pass door closing any tips on correct way to shim the body

[Geoff C.]

Jeopardy: "What are shims used for" *NM*

[John O.]

add shims at mounts till it's lined up right *NM*

[Dick W.]

Re: Body mount shims 1971

Describe the fit as it is now. They someone can make the suggestions as to where to install shims

[Chuck S.]

Re: Body mount shims 1971

Generally, the frame is the component that is dimensionally different requiring shims to fit the body floor flat and level.

During assembly, shim quantities were marked on the frame with wax crayon at each body mount location. There will probably be one location with zero shims, and all other body mount locations have shims added to keep the body floor flat and level relative to that point. Short of raising the body enough to read the original crayon marks on the frame (if they are even readable), there is no good way of duplicating the original number of shims. Of course, if the hack restorer you bought your car from did a body-off restoration, and PAINTED THE FRAME without duplicating the shim marks, then you are SOL...revert to Plan B.

One other option is to estimate the number of shims required at each location. In practice this isn't a bad plan, because over the years members have found that bodies settle causing the optimum number of shims to vary from the original setup. Years ago, someone posted a procedure for estimating shim numbers that sounded good...I've never had to do it myself. This and much more has been written about shimming over the years. I recommend a search of the archives using "body shims"...BE SURE to select "ALL terms" instead of the default "ANY terms".

[Vincent F.]

Re: Body mount shims 1971

Thanks Chuck,the shim procedure is more important than most would think,to many or to little in some areas could cause stress crack,tight door jams ect,car cant be shimmed on jack stands either when you set on wheels it all changes.I think you should set car on wheels,shim body,check door and gaps,then tighten bolts,you agree?

[Chuck S.]

Re: Body mount shims 1971

If I told you how to shim a body, the blind would be leading the blind.

Many guys before you have done this, and they were aided by some smart, experienced body guys that may not be on here today...I would do the research.

[Jim T.]

Re: Body mount shims 1971

Vincent C3 Corvettes left the factory at St Louis and Bowling Green starting with the 73 model year and ending with the 82 model year with rubber body mounts. Rubber body mounts were used before 1968 in the C2 Corvettes. Someone that owned your 71 most likely changed from the original 68-72 aluminum mounts to the 73-82 rubber mounts because of what had been written in automobile magazines after the 73 models were built about the benefits of having the rubber mounts. There is a difference with some of the body mounts for the 73-75 convertibles and the 73-82 coupes.

[Vincent F.]

Re: Body mount shims 1971

THanks Jim,I think if you use rubber mounts on 68-72 cars you will develop more stress cracking.In 73 they started using different hardnera in fiber glass to make it more flexible,hence rubber mounts could be used.Earlier fiberglass is to brittle for rubber mounts.I maybe off base here,I read it somewhere

[Michael W.]

Re: Body mount shims 1971

I think this comes as a great surprise to many of us. Could you quote the source please?

[Stephen L.]

Re: Body mount shims 1971

Why are rubber mounts ok fom 63-67 then taboo from 68-72 and ok again after that?????? If early glass was brittle didn't that cover 63-67 too????