1963 Trailing Arm Alignment Kit w Shims

[Lawrence E.]

Hello

How do you install the shims for a 63 without drilling a hole and using the cotter pins ensuring the shims do not fall out? Do you need to cut down the shims and or use epoxy?

thank you, Lawrence

[Harry S.]

Re: 1963 Trailing Arm Alignment Kit w Shims

Is this what you are using? This style was used till May or June 1963 then it changed. If not tightened properly they can fall out.

[Duke W.]

Re: 1963 Trailing Arm Alignment Kit w Shims

If installed properly they won't fall out. The shim pack should be a slight interference fit, and the last one installed, a thick one, should require light tapping with a small hammer to drive home.

Then push the shim packs down until the narrow ends hit the bottom of the frame window and torque the trailing arm nut to spec.

Duke

[Lawrence E.]

Re: 1963 Trailing Arm Alignment Kit w Shims

Thanks Duke -- this info is very helpful ...

I do have a couple follow up questions if you don't mind ?

Could you elaborate just a bit ... when you say "slight interference fit" ... meaning they may seem like they won't fit but they can be manipulated to fit ? Also, I provided a pic of the kit below I just purchased ... There are 3 sets of cotter pins .. for a "correct 63", should I use any of the cotter pins?

[Lawrence E.]

Re: 1963 Trailing Arm Alignment Kit w Shims

Sorry, I missed your post Harry

Here is a pic of the kit below I just purchased ... There are 3 sets of cotter pins .. for a "correct 63", should I use any of the cotter pins? And will those shims pass NCRS?

[Michael W.]

Re: 1963 Trailing Arm Alignment Kit w Shims

Those shims are not correct for a'63,slotted shims and cotter pins are for later cars. Your shims should like the ones in Harry's pic if it was built in that date range.

[Lawrence E.]

Re: 1963 Trailing Arm Alignment Kit w Shims

UGGGGGGGGGGGGGG

Who sells correct shims?

[Leif A.]

Re: 1963 Trailing Arm Alignment Kit w Shims

Lawrence,
Here is a link to LIC with the correct shims. One pair of the cotter pin(smaller ones) are used to go thru the long bolt once the nut is torqued...see hole in end of bolt.

https://www.parts123.com/parts123/yb.dll?parta~dyndetail~Z5Z5Z50000370a~Z5Z5Z5AAGMQ~P59.00~~~~S57V0ON9AU64201117870a~Z5Z5Z5~Z5Z5Z50000370a

[Joe L.]

Re: 1963 Trailing Arm Alignment Kit w Shims

UGGGGGGGGGGGGGG

Who sells correct shims?

Lawrence-----

Just so you understand, the shims you have will be 100% functional for your application even though they are not 100% NCRS-correct. You would use them without the cotter pins and install as Duke described. Cotter pin retention was not used until L1969-E1970. If you had purchased shims from GM since about 1971 the style you have is the style you would have gotten.

If you want NCRS correct shims for the 1963-only application, I would expect that Long Island Corvette, among others, would have them.

[Joe R.]

Re: 1963 Trailing Arm Alignment Kit w Shims

Lawrence,

Do yourself a favor and find a shop that will align your 63 and has done Corvettes in the past with a good reputation. You cannot align your Corvette at home in your garage. It would be just guess and luck.
The shim kit you have will work just fine when used by a competent technician.
Find one!

JR

PS. So you will loose a couple of points in judging. Usually loosing a couple of points won't break the bank. Maybe!

[Duke W.]

Re: 1963 Trailing Arm Alignment Kit w Shims

"Could you elaborate just a bit ... when you say "slight interference fit" ... meaning they may seem like they won't fit but they can be manipulated to fit ? Also, I provided a pic of the kit below I just purchased ... There are 3 sets of cotter pins .. for a "correct 63", should I use any of the cotter pins?"


Interference fit means you can't slide the last shim in with your fingers. It must be tapped slightly with a hammer to drive home as I said previously.

Until late '63 the slotted shims as pictured in post #2 were used and the trailing arm bolt/nut were plain, not set up for a cotter pin. The '63 AIM sheet shows the late configuration with the captured shims, and bolt/nut for a cotter pin.


It's possible to set rear toe in your garage, but it's a lengthy tedious process that would take more time than I have to explain, but if you shoot me an email I will send back my phone number if you want me to explain on the phone.

You need a collection of shims as shown in post #2. I think OE shims were available in thicknesses of 1/32, 1/16, and 1/8 and maybe 1/4". These type of shims are easy to replace, so a competent alignment shop with modern four wheel equipment should be able to do the job. It's more difficult with the later captured shims because the spring load must be supported to unload the trailing arm prior to the bolt being removed.

The tech sets the toe of each wheel at 1/32". Then he installs shims to fill the gap on both sides using at least one 1/32" shim on both inside and outside. Then he checks that the toe is still in spec, and proceeds with removing a thick shim, installing one more 1/32" shim on the outside, then tap in the thicker shim. Toe should now be between 1/32 and 5/64" per wheel.

If his equipment reads toe in degrees the toe in inches must be converted to degrees using the fact that a small angle, in radians, time radius (which is tire radius) is equal to toe. You should understand this. If the alignment tech doesn't, go someplace else and find a tech that does.

Here's the computation for one wheel assuming a 27" diameter tire.

Toe in radians = 1/32/13.5 = .0023148

Using the 2 pi radians = 360 degree conversion factor.

Toe in deg. = .0023148 (360/6.2832) = .1326 deg.

Both rear wheels should be as close to this as is possible to obtain.

Duke

[Richard G.]

Re: 1963 Trailing Arm Alignment Kit w Shims

Also note there is no hole, or other provisions for a cotter, on the pivot bolt in 63.