The engine serial number shows the manufacturing plant signified by a letter (F for Flint, T for Tonawanda, etc.), the month of manufacture, the day of manufacture, and the transmission and engine type represented by a two or three letter code. A typical engine serial number would be F1005FA. The F represents the manufacturing plant (Flint), the 10 signifies the month of manufacture (October), 05 signifies the day of manufacture and FA signifies the engine and transmission type. Beginning with 1968 cars, a VIN is stamped on the cylinder block next to the engine serial number. The VIN (up to 1971) is the same as the car serial number stamped on the instrument panel except that it does not include the four numbers representing body style. In 1972, the VIN changed somewhat. A typical VIN for the 1972 Chevrolet might be: 1Q87F2F000001 identifying this particular car as the first (000001) 1972 Chevrolet to roll off the Flint assembly line. It includes the manufacturer's identity number (number 1 representing Chevrolet products), a series code letter (B representing Impala), a two digit body style number (87 representing 2 dr. Sport Coupe), an engine code letter (letters listed below), a one digit vehicle year number (2 representing 1972), an assembly plant letter (F signifying Flint), and a unit number signifying order of production. According to the VIN, this car had a 307 cu. in. engine with 2-barrel carburetor represented by the engine code letter F.
This basic format is utilized through the 1978 vehicle year, although specific letter/number designations may change from year to year.
INLINE 6-CYLINDER ENGINES
On 6-cylinder engines, the serial number is found on a pad at the front right-hand side of the cylinder block, just to the rear of the distributor.
On all V8 engines the serial number is found on a pad at the front right-hand side of the cylinder block, just below the cylinder head.