Cylinder Head Assembly: Description and Operation

Fig. 3 Cylinder head assembly:

The cast-aluminum cylinder head, Fig. 3, consists of four cylinders, each containing four valves. Both intake and exhaust valves use narrow diameter valve stems to provide minimum friction with optimum air flow. Rotators, used on all valves, are located at the bottom of the valve spring to eliminate any effect on valve train reciprocating mass.
The combustion chamber is designed to provide fast burn at high specific output. Each chamber contains a sumped piston and a centrally-located spark plug. A combustion chamber of this design maintains combustion stability and eliminates the need for external exhaust gas recirculation.
Both intake and exhaust valve ports are a Siamese design. Fuel injectors are positioned in the intake port to obtain optimum targeting.