Chevy head casting numbers identify the type of engine, displacement in cubic inches, year of manufacture and the size of the combustion chamber and valve heads. The head casting number provides valuable information about the engine configuration.
Chevrolet have manufactured a wide range of engines over the years with many variations, so accurately identifying an engine can be difficult. Although it is not possible to directly decode the casting number, online databases provide specific information based on the number.
The head casting usually has the number located under the valve housings, and the number is six to eight digits long and accompanied by a four digit date code.