Crankcase/Crankshaft

Crankcase

The proven closed-deck design of the aluminum-alloy crankcase is used. In this design, the housing and coolant ducts around the cylinders form a closed system. This creates a very rigid engine assembly, minimises cylinder delays, and results in low oil consumption as well as a reduction in the amount of combustion gases that make it past the piston rings into the crankcase (blow-by gases). The lightweight, rigid engines therefore ensure lower fuel consumption and a long service life.







The alloy used for the crankcase is the familiar and proven hypereutectic light metal alloy AlSi17Cu4Mg, in which silicon crystals form. In order to create a wear-resistant surface on the cylinder lining, these silicon crystals are exposed through multiple special honing processes. A fully aluminum bedplate is used in order to reduce weight. The forged crankshaft has five bearings and a very rigid design to reduce vibrations in the engine block.

The cylinder head and camshaft housing have been integrated into a one-piece aluminum cylinder head on the V8 engines. At the same time, the arrangement of the intake port and injector has been optimally designed for direct fuel injection. The water jacket ensures that the cooling system has sufficient reserves even in the cylinder head, which is subject to substantial thermal loads. The one-piece design also reduces the weight slightly.


Crankshaft







A lighter crankshaft is used in the Panamera S as a lightweight design measure aimed at reducing weight. This is adapted to suit load demands specific to naturally aspirated engines. The diameter of the connecting rods is reduced compared with the previous V8 crank drive used in the Cayenne and the crankshaft has a larger counterweight radius. As a result, the crank drive is 5 lbs. (2.3 kg) lighter than the previous V8 crank drive. The crankshaft in the Panamera Turbo is also weight-optimized. The crankshaft has a larger counter-weight radius than the previous V8 crank drive.

Crankshaft Bearings

In order to reduce the weight of the naturally aspirated engine in the Panamera S, the diameter of the connecting-rod bearing pins was reduced from 54 mm to 52 mm. Since the connecting rods in the naturally aspirated engine were also weight-optimized, it was also possible to reduce the weight of the balancing weights on the crankshaft. A larger counter-weight radius means that the further out the weight is attached, the lighter this can be.