CRANKSHAFTS

Crankshafts are the most stressed component in a racing engine. The crankshaft must transform the energy from the combustion into usable shaft power. A connecting rod is attached to crankshaft on a bearing which has to be supplied with lubrication oil through small oil passages (in the crankshaft). The cyclical nature of the power stokes along with the reciprocating forces required to move pistons, rings, pins, connecting rods and gases up and down create harmonic oscillations that twist the crankshafts and can cause it to fail. The forces related to the oscillations and twisting are exaggerated when the engine speeds are increased in an effort to make more horsepower from any given engine displacement. The forces acting on the crankshaft increase at the square of the speed of the engine. This means that a Porsche air cooled engine operating at 6000 RPM could see tensile forces from the attached reciprocating mass of connecting rod/piston that are 1,980 times that mass. At 8500 rpm, the same engine with the same connecting rods/pistons would be generating forces of 3,971 times that mass (double). If the reciprocating mass of the connecting rod and piston are 750g then the peak forces at 6000 and 8500 rpm would be 3,200 lbs and 6,600 lbs respectively. Clearly the crankshaft needs to be specially designed to handle to this task and allow for safe and reliable operation under such massive punishment.

At Elite we work with world renown crankshaft manufacturers to produce the optimal crankshafts for our systems, driven by the geometries selected for the engine build as well as the physical attributes of the parts that will be connected to the crankshaft (pistons, connecting rods, bearings, flywheels, lay shaft gears, oil pumps etc.). Making these parts lighter will reduce the load on the crankshaft, yet at some point there is a tradeoff between the structural integrity of a part and the minimum weight that it can be manufactured at (see pistons and connecting rods). Most of the Elite Silver Systems use a crankshaft that started life as an original Porsche part which was subsequently modified by Elite to increase its ability to operate in the environment that it will be subjected to. We use radiuses that are different than the OEM, use oiling details that will allow these parts to live at the much higher speeds, and use heat treating technologies to enhance the material properties of the metal they are manufactured from.

Most of the Elite Gold and every Platinum System use specially designed and manufactured crankshafts that are specifically tuned to the rest of the engine parts in the system. Although it may be possible to use them in other applications (outside of the Elite systems) this would require engineering judgment from the end user to prevent any parts compatibility problems from arising.