Cylinder Head Assembly: Description and Operation

Featuring 24 valves (4 per cylinder), twin camshafts and crossflow scavenging, the cylinder head is designed for an extremely high engine efficiency. The head is split into an upper and a lower half to facilitate and ensure correct assembly.

Liquid sealing compound (liquid gasket) is used to seal the joint between the halves. The joint is assembled by means of 48 bolts and four guide pins, forming a rigid construction with a low noise level.

Since the head joint is in the same plane as the camshaft axes, the camshafts are supported in both halves without the use of a separate bearing cap assembly. The valves, valve springs and tappets are supported in the lower half, while the upper half functions as a combined valve and camshaft cover. The oil channels cast in the underside of the upper half ensure adequate lubrication of the camshafts and hydraulic tappets. The camshafts are supported in seven bearing positions machined in each of the halves. (The head is replaced as a complete unit comprising both halves.)