Technically Speaking...

Introduction to Corvette Restoration

A big part of the Corvette and the history of these fantastic cars is the restoration of the earlier models such as the C1, C2 and the C3. The C4's are also become a collectable and are being restored back to the way the first appeared from the factory.

Thanks to Corvette enthusiast and an organization called the National Corvette Restoration Society or NCRS many of these great cars are now back to looking like they just rolled off the assembly line and in some case even better, which is not always a good thing, but more on that later.

 

When someone decides that they want to restore an older Corvette or purchase one the first item of business is to see exactly what you have as far as original equipment. In many instances what appears to be a correct car can be completely incorrect. A common phrase in the Corvette hobby is "this is a NUMBERS MATCHING car". What does that really mean? Well to some it means everything and to others not so much as we will see.

 

All cars have an identification number or what is known as the Vehicle Identification Number or VIN for short. This number is a unique number assigned to each vehicle and no VIN's are alike. This numbers are stamped or etched on to a plate that is then attached to the body of the car. From 1953 through 1955 the VIN plate was found on the left hand door pillar just below the courtesy lamp door switch. From 1956 through the early 1960 model year the VIN is on the door hinge pillar just below the upper hinge. This plate shows that it is a Corvette(E), 56 model year(56), built in St. Louis(S) and it was the 1,307th Corvette to come off the line(001307). Shortly after the 1960 production began, this plate was relocated to the steering column inside the engine compartment and remained there through the end of the 1962 production year. In 1963 with the introduction of the new Stingray, this plate was attached to the instrument panel support brace below the glove compartment. It stayed in this location for the entire production of the C2 generation. In 1968 to comply with federal law, the vehicle number was required to be visible from the outside. So in 1968 and from then on the plate was attached to the A-Pillar (windshield post) or to the dash board where both locations would be visible from the outside. This number was also stamped on to the Corvette frame in a few different locations. Finding that the VIN plate and the frame stamp match, does not indicate a matching numbers car. There is a matter of the engine, carburetor, distributor, generator, alternator and starter. All of these parts just mentioned came off the line with their own numbers. Although these numbers were the same for each car, it was different in each year.

 

The vehicle number did not indicate the engine type except in the 1955 model year. And that was indicated by the first letter in the Vin would be a V and that indicated that the car was equipped with the new 265 V8 engine option. Not until 1972 did they go back to indicating the engine type in the VIN and it was the fifth digit in the VIN. If it was a K it indicated a 350 ci 200 hp, L was a 350 ci 255 hp and a W was for the 454 ci 270 hp engine.

 

Corvette engines from 1953 through 1996 had an important number stamped on them. The 1953 - 1955 six- cylinder engines had this number on a machined pad near the distributor opening. The 1953 engine had the prefix LAY preceded by a six digit serial number. For 1954 - 1956 a seven digit serial number followed by an "F" for Flint, Michigan where the engine was built and two numbers indicating the year of build. So it would look something like this, xxxxxxxF56. In 1957 this stamped number started with a letter indicating the build plant "F" was for Flint through 1966 and it was changed to "V" for Flint after 1966. Next came three or four digits designating the date the engine was assembled. The final two characters were called the suffix numbers even though these were not numbers at all, but alpha characters. Later these two suffix numbers were increased to three characters. This number is located on a machined pad on the block just a head of the right side cylinder head. This carried through 1991. From 1992 - 1996 this location changed to the rear of the engine block, usually on the driver's side, but sometimes on the passenger's side.

 

The first time that you could actually match a factory installed engine in a specific body came in 1960. Along with the manufacturing location code, month and year of assembly and engine code, the six digit serial number from the VIN was also stamped into the machined area of the block. Now with the sequential build number/serial number on the block there was a true way to verify that you were getting the original engine (hopefully) that was installed at the factory. Looking at this numbers we know the engine was assembled in Flint (F)on March 9th (0309)and it is a 327 ci rated at 250 hp(RC) out of a 1962 Corvette. Because the demand for the early model Corvette's (C1 & C2) is so great, you need to be aware that just because the numbers on the block match the VIN and the engine code is correct does not always mean everything is right with the car. People have been known to re-stamp the engine block. Many times the original engine has been rebuilt and during the rebuild the head surface of the blocked was decked and in this process the number pad is machined clean and the numbers no longer exist. This is when someone tries to re-stamp the all important numbers. If the numbers have been machined off the block there is another area to look at to see if the engine may be a legitimate engine. This is a casting on the block itself called the engine date code. These engine date codes are identified by a letter for the month starting with "A" and ending with "L". January is indicated with the Letter "A" and December with the letter "L". Following the letters will be a one or two digit code indicating the day of the month and finally a single digit indicating the year. It would appear something like this B16, or February 1, 1966

Courtesy of Greatamericansportscar.com.