Four-valve Cylinder Head
    (top view)

The cylinder head of a 4 valve engine with its both camshafts is displayed above. The valves are operated directly via hydraulic tappets. In the middle openings are visible for the spark plugs and perhaps ignition wires or single spark ignition coils. On the top right a socket is poured in above the upper camshaft for an inductive pickup. It informs the engine management control system about the position of the camshaft. The camshaft features a corresponding wheel with four tips. Obviously this cylinder head is equipped with a Motronic with cylinder-selective injection and ignition. 06/08