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For a broad acceptance of electric vehicles, the trade-off between all electric range and battery cost respectively weight represents the most important challenge. The all electric range obtained under real world conditions most often deviates significantly from the nominal value which is measured under idealized conditions. Under extreme conditions - slow traffic and demanding requirements for cabin heating or cooling - the electrical range might become less a question of spatial distance but even more of total operation time. Whereas with conventional powertrain, high flexibility of the total driving range can be obtained without sacrificing cost, with a pure battery vehicle this results in extreme high cost and weight of the energy storage. Therefore the difference between the typical daily driving range (e.g. in Germany 80-90% is below 50 km) and the minimum total range requested by most customers for acceptance of battery vehicles (200- 250 km), becomes essential.

Significant weight reduction on the powertrain can only be achieved by the combined use of lightweight materials with specific design approaches. The component with the highest contribution to the engine weight is the crankcase. As the central component with many integrated functions, new crankcase concepts require comprehensive development in view of the mechanical and acoustic behavior. After basic concept development and FE-analysis a test engine was built to evaluate the forward-looking light-weight concepts under realistic conditions. Especially the comparison of modern cylinder running surfaces was a topic of extensive material investigation and engine durability tests. Both Aluminum and Magnesium were investigated as material for the crankcase of the test engine. Beside the functional aspects the production cost of lightweight concepts is the decisive issue for their implementation in volume production.

During the past years advances in fuel efficiency of car engines did not result in the expected reduction in overall fuel consumption of new car generations. One reason is the increasing vehicle weight. In an overall–weight analysis of an automobile the engine and as part of it, the crankcase represents a single component with a high weight reduction potential. This paper discusses weight reduction strategies using lightweight materials and modern design approaches. The application of lightweight materials for new crankcase concepts implies comprehensive design considerations to achieve weight reductions as close as possible to the potential of the selected material. A specific approach for inline and V–engine crankcase concepts is discussed in detail. Engine weight reduction can also be achieved through substituting large and therefore heavy engines with small high performance engines.

The principal engine used in passenger cars is, and in the foreseeable future will be, the SI Engine. This paper summarizes AVL's experience in developing SI Engines for these vehicles. Special attention is given to the new targets of SI Engine development and the resulting design strategies during the concept phase of new engine families. The new modular concept of engine families includes a broad range of different engine designs like three to five cylinder inline and six to ten cylinder V-block engines, direct injection or fully variable valve actuation. It is shown that the design of central engine components, for example, that of the cylinder head, can be adapted for the different SI valve-train concepts by simply switching specific modular components.