I have the aim and the NCRS judging guide. They are both very good information books but I need more. I have the part numbers for the attaching hardware i.e. nuts, bolts, screws but that does not describe the actual dimension, head, length, diameter and plating of the item. Is there somewhere I can go for this needed info?

 

GM had cross references to the engineering drawings on those parts. It probably still exists somewhere. If you specify what fasteners you need to know about, maybe you can get the info here. If you have a lot of parts, you need to find a P/N cross reference.

 

I started a thread some time ago on a similar subject. Here is the link to the thread:

http://forums.corvetteforum.com/c3-g...ave-a-p-n.html

 

Hi TCG,
The best single source for fastener dimensions that I've found is the CORVETTE PARTS BOOK that was published by Motorbooks International. It doesn't have everything but it does have a lot.
Next, I'd recommend the CORVETTE CHASSIS RESTORATION GUIDE by Joseph Tripoli. It has a few pages of chassis fasteners showing size, head-mark, and location.
Another good source is the Paragon Catalogue. It lists the sizes of many of the fasteners they sell. They also have a wall chart that has head-mark and size info on the fasteners they sell.
You have to be a bit of a detective since the info isn't in just one place.
And then you mention FINISHES... many more questions, various answers and opinions.
Regards,
Alan

 

The GM Corvette Illustrated Parts Catalgoue usually lists screw and bolt sizes.

 

I have a parts & illustration catalog for '53-'74 Corvettes published in 1974. It shows the bolt part number and the size (like 1/4-20 x 1"). If the illustration in the parts catalog, AIM or service manual is clear enough you can see what the head type is. You can also determine the hardness of the fastener by the markings on the head in most cases. The only thing left is the finish which you may be able to tell by sight (black oxide, cad, chrome, etc).

I agree with others that finding the actual spec reference for the fastener would be difficult.

 

Paragon offers a laminated poster that shows actual pics of the fasteners and their application for corvettes. Give them a call and you might be able to get one.

 

Actually, very little hardware is included in the Corvette Chassis and Body Parts Catalog. If you look at the illustrated pages (sometimes refered to as the green pages) in a Corvette Chassis and Body Parts Catalog it will tell you what group to find a part in. Hardware will be shown with a Group number starting with 8.9, such as; "Bolt (5/16"-18 x 3/4")....8.900", or "Lockwasher (3/8")...8.931". If you try to find Group 8.931 in your Chassis and Body Parts Catalog, you'll see it isn't there. That's because parts starting with Group No. 8.900 are found in a separate Catalog, the GM Standard Parts Catalog. The green pages of the Chassis and Body Parts Catalog will give you a size, but no other information on hardware

The Standard Parts Catalog lists all hardware used by GM, including the thread size, overall and thread length, GM part number, material grade, the finish (cad, zinc, black oxide, stainless, etc.), how many to a package, etc. Unfortunetly, hardware is arranged in a Group by type (8.900 being all bolts, starting with: Bolts, hexagon head (English), then Bolts, hexagon head (Metric), next Bolt, hex w/flat washer (first in English and then the Metric chart) and so on.....Group 8.900 is followed by 8.903, then 8.906, etc.). To find a bolt, nut, washer, etc., you have to know it's Group number or find the it's Group by matching it to it's description. Once you find it's Group, you go through the chart (which lists the part by size, smallest to largest) and look for the part you want. There is no index to tell you what Group to go to to find a particular part number.

As an example, if you want the acorn nuts that hold the seat hinge covers on 79-82 seats, the illustration in the green pages of the Chassis and Body Parts Catalog tells you "NUT, Acorn (3/16")....8.921. But a quick look through the Parts Catalog and you will see that 8.921 is not there. This acorn nut is in the Standard Parts Catalog. To find it in the Standard Parts Catalog, you must go to Group 8.921 and then go down the list of different sized acorn nuts, until you find 3/16", which is part number 9437976. If you didn't know the Group No., you would have to know that GM called this nut an; acorn type stamped nut, to find it's group.

GM has not printed the Standard Parts Catalogs (or any other paper catalogs) in about 20 years. If you can find a Standard Parts Catalog, you'll find that they are very useful. Besides hardware, they include labels, electrical connectors, grease fittings, wire ties, snap rings, assorted clips, light bulbs, and many other small parts. Unfortunetly, being at lease 20 years old, many of the parts found in them have since been discountinued, and others have had their part number changed.

There is no single source for hardware sizes, markings or finishes. The Paragon chart (and their catalogs) are a good place to start, but don't have every answer. The NCRS Judging Manuals are good too, but many of the ones for earlier years, don't have the wealth of information found in the newer editions, for more recent year Corvettes.

That's just part of the fun of the hobby, the hunt for information and details.