Cylinder head s are an amazing piece of engine design. Intricately machined to very strict dimensions and made of very materials, the cylinder head has to perform its function in the toughest driving conditions and intense heat.

In an internal combustion engine, the cylinder head sits above the cylinders (no surprises there) and makes up part of the combustion chamber as well as housing the location of the valves and spark plugs.

In the overhead valve engine or flathead engine, the valve components are contained within the block. The cylinder head block is simply bolted to the cylinder bank with a head gasket in between. In the overhead cam engine, the top half of the cylinder head contains the camshaft and valve components.

The cylinder head needs to be precisely manufactured, as it is the key to the performance of the engine. The shape of the combustion chamber, inlet passages and ports determine how efficient the engine will be and how good the compression ratio will be. Straight engines only require one cylinder head. A V engine usually has two cylinder heads. A Boxer engine also has two cylinder heads.

We hope that helps answer the question ‘What is What is a Cylinder Head?’!

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