Identify cylinder heads by using the engine casting number and family. Casting numbers are typically stamped to one of the sides of the cylinder head. The engine family determines the design and layout of the cylinder head. Each cylinder within the cylinder head is numbered and identified individually.
The VIN number of a vehicle is sometimes used in the process of identifying a specific cylinder head. However, this practice is less common. Use of the casting number or engine family are more reliable preferred methods, according to American Cylinder Head. Some heavy-duty diesel engines, such as those intended for locomotives, large trucks, marine and industrial purposes, are designed with a cylinder head for each individual cylinder, but the cylinder heads are still identified within a family of engines.