Valve gear

For engine S63 TOP, the fully variable valve stroke adjustment is used in addition to the double VANOS. The valve gear itself consists of known components. The rocker arms and intermediate levers made of shaped panels are new. More weight could thereby be saved in connection with the light construction camshaft. One tooth sleeve chain is used for each cylinder bank to drive the camshaft. Chain tensioner, tensioning rail and slide rails are common parts for both banks. The oil spray nozzles are integrated in the chain tensioner.

Valvetronic 

The Valvetronic consists of the fully variable valve lift timing control and the variable camshaft timing control, 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 placed on the intake and exhaust side. The opening time and closing time, and thereby the opening period and valve lift of the intake valve can thereby be selected freely.

The Valvetronic of the 3rd generation is already used in the engine N55.

Valve lift adjustment 

As shown in the graphic below, the Valvetronic servomotor is installed on the intake side of the cylinder head. The eccentric shaft sensor is integrated in the Valvetronic servomotor.

Fig 1: Identifying Valve Gear

Courtesy of BMW OF NORTH AMERICA, INC.

VANOS 

The following differences apply to engine S63 compared to engine S63 TOP:

• The adjustment range of the VANOS was expanded by reducing from 4 to 5 wings. (Intake 70° crankshaft, exhaust 55° crankshaft)
• The weight could be reduced from 1050 g to 650 g by using aluminum instead of steel.

Fig 2: Identifying VANOS

Courtesy of BMW OF NORTH AMERICA, INC.