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Valve gear (Ver.2): Notes

The valve gear consists of the fully variable valve lift timing (Valvetronic) and the variable camshaft timing control (double VANOS), which enables a free choice of closing time for the intake valve. Valve lift timing only takes place on the intake side; camshaft control takes place on the intake and exhaust side.

Throttle-free load control is only possible if the following variables can be controlled:

Result: The opening period of the intake valve is variable.

Fig 1: Identifying Valve Gear Related Components
G09910348Courtesy of BMW OF NORTH AMERICA, INC.
Index Explanation
1 Torsion spring
2 Eccentric shaft
3 Exhaust camshaft
4 Exhaust VANOS adjustment unit
5 Exhaust roller cam follower
6 Exhaust hydraulic valve clearance compensating element
7 Valve spring, exhaust valve
8 Exhaust valve
9 Valvetronic servomotor
10 Intake valve
11 Valve spring, intake valve
12 Intake hydraulic valve clearance compensating element
13 Intake roller cam follower
14 Intermediate lever
15 Intake camshaft
16 Intake VANOS unit