How many SHIMS are normal at the frame-horn to Radiator Support location?

[Scott S.]

I realize it varies from car to car, but approximately how many shims are commonly found where the radiator support attaches to the frame-horns? It's looking like I need about 3/4" worth of shims on each side, or 12 shims at 1/16" each.

That seems like a LOT...


1967 AIM: UPC 11-13-A5, Item 32, GM 3755670

[Joe R.]

Re: How many SHIMS are normal at the frame-horn to Radiator Support location?

Scott,

There are usually two shims spot welded to the frame at each end. I have never seen that many shims used on any mid-year frame. Usually the earlier frames (63-64) have as many as four shims but the later (65-67) only one or two.
Did you notice or catalog the shims when you pulled the body?
Remember that 1 thru 3 are level and at the same plane on 64-67 frames and you should work from that assumption if you started with a new frame or body that was never shimmed to the frame you are using.
By adding just a couple of shims to the #3 and #4 position you will drastically effect the number of shims needed at the radiator support.

Make sure you are doing all this shimming WITH the doors attached especially if it is a convertible.

Procedure should be as follows:

1. Shim body to the #1,#2,#3 as a box. I start with 4 shims at each position.
2. Shim #4 until the door gap is good at the rear of the doors. This is assuming that the door is fitting properly in the front.
3. Check the radiator support and shim as necessary.

The above procedure should only be used if the body is not original to the frame or the frame is being changed. If the body is original to the frame you should have cataloged the number of shims at each body position before pulling the body.

Just remember that GM assumed the body was flat as it was built on a very rigid trolley and the frame needed the shims to mate with a perfectly flat body.

There is a great article in Volume 38, Number 1 of "The Corvette Restorer" on page 10 by Jeff Blakeslee. Building a dolly as Jeff explains should be basic to any restoration project.

If this all sounds confusing, get out your 64-65-67 Corvette Shop Manual Supplement and give me a call one evening.

JR

[Wayne W.]

Re: How many SHIMS are normal at the frame-horn to Radiator Support location?

4 is commom. Seldom do you see many more than that.

[Scott M.]

Re: How many SHIMS are normal at the frame-horn to Radiator Support location?

I have four shims tack welded to my '67.