MAHLE Engine Systems and Components

Evotec 2 lightweight piston for gasoline engines

On the compression stroke of an internal combustion engine the connecting rod applies pressure to the piston at an angle, placing greater force on the "thrust" side. Past practice has been to design asymmetrical piston skirts with the larger area of the skirt on the thrust side. The purpose was to disperse the load over a greater area and reduce unit pressure.

MAHLE has reversed this design to provide a narrow thrust side, combined with a wider, elastic anti-thrust side to guide the piston. In so doing they introduce uniformly high structural strength, rigidity, and smaller contact area on the thrust side which lowers engine friction, increases load capacity, and reduces piston weight; all necessary for high pressure (turbo charged) gasoline engine performance. Piston cracking has been all but eliminated. A significant additional benefit is the reduction of noise, vibration and harshness due to the stiffer contact area on the thrust side. Audi is the first customer.