[TMS] MAHLE Proposes Extra-Supercharged Compact Engine

Oct 30, 2007
Motohiko Hamada, Nikkei Automotive Technology
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MAHLE of Germany exhibited an engine that employs numerous new technologies at the 40th Tokyo Motor Show (open to the public from Oct 27 to Nov 11, 2007).

The company does not intend to commercialize the engine, but exhibited it in order to break into the engine development consulting business in Japan. The company mounted a lot of parts it manufactured on the engine to appeal that it is capable of creating actual products. The company emphasized the difference from the competitors such as AVL and Ricard.

The company thinks a 1.2-L (or equivalent) 3-cylindar supercharged engine will be a standard power unit for passenger cars weighing less than 1.6t in the future. Compared with the currently-standard 2.5-L engine, the emission will be reduced by 50%, resulting in the reduction of fuel consumption by more than 20%.

The power unit is a double-layer supercharged engine developed by MAHLE Powertrain in Northampton of England. It generates a power of 120kW per liter. It attained a high-specific power using MAHLE's products.

The forged piston, cam axis, direct-injection waterless intercooler, cooled EGR (emission gas recirculation) system, which reduces fuel consumption during full throttle, injection valve cooling system, intake/exhaust valve timing variable structure and cooled light valve are made by the company. The company acquired Cothworth of England and now can produce large aluminum moldings, including cylinder blocks and cylinder heads.

To minimize the fuel consumption, the friction loss was also reduced. The engine employs a DLC (Diamond-Like Carbon) coated piston, a NIKASIL (Ni-Si) coated cylinder sliding surface and a PVD (Physical Vapor Deposition) coated piston ring.