Cam transmission
The engine is equipped with four overhead camshafts - two per cylinder head. A gear wheel mounted on the crankshaft drives the so-called primary chain, which is toothed. A self-adjusting hydraulic chain tensioner ensures that the primary chain has the correct tension. The chain is controlled with the help of three chain control guides.
Scheme 979
The distribution chain drive the distribution pinion of the front and rear bank's timing chains. A timing chain runs from the distribution pinion up to the respective cylinder head. Each timing chain has two guides and a self-adjusting hydraulic tensioner.
Scheme 980
The exhaust camshaft has a silent pinion while the intake camshaft has a hydraulic cam phasing mechanism (CVCP). The camshafts actuate rocker arms with roller bearings (aka roller finger followers) that are shaped like a ball cup at one end. This ball cup meets the ball-shaped upper part of the hydraulic valve clearance balancer. The other end of the rocker arm actuates the valve stem. The hydraulic valve clearance balancers keep the clearance between the rocker arm/roller bearing at zero. The valve clearance balancers thus do not participate in the movement of the valve mechanism.
Scheme 981
The valves are steel with chromium-plated spindles. The exhaust valves are sodium cooled.
