Federal-Mogul Unveils Lighter Piston for Downsized Engines

Federal-Mogul Corp. begins production later this year on a new aluminum piston design it says is stronger and as much as 20% lighter than previous-generation designs.

Called Elastoval II, the piston will debut in an unidentified European passenger car this autumn. Federal-Mogul says several other vehicle manufacturers are validating the new design.

The walls of the Elastoval II piston are as thin as 2.5 mm compared with 4 mm for previous architectures. Other weight-saving features include shorter piston pin bosses and asymmetric skirt widths.

Yet the new piston is designed to withstand the 37% higher specific power output (up to 130 kW/liter) likely as carmakers downsize and turbocharge engines, according to Federal-Mogul. The company also notes that the Elastoval II was developed to handle peak combustion pressures as high as 160Bar compared with today's 100Bar.

To handle such pressures while reducing weight, the internal surfaces of the Elastoval II piston include crown reinforcing ribs and complex-curve side panels. Federal-Mogul says it was able to reduce skirt width to 50% of bore diameter on the thrust face and 45% on the non-thrust face without compromising noise or scuff performance.