cylinder heads are also classified according to the arrangement of valves. General classifications are “F” Head, “I” Head, “L” head, and “T” Head. In “L” head designs, both the inlet & exhaust valves are on one side of the engine and a single camshaft operates them.

However, the “I” head engines have the valves in the head which operate through push-rods and rocker arms. The “T” head engines have the inlet valves on one side and the exhaust valves on the other side which requires two camshafts. The “F” types have the inlet valve in the head and exhaust valve in the cylinder block and employ one camshaft.