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Downsizing, down speeding and hybridization are becoming a standard in the automotive industry. This paper was initiated to answer Automobili Lamborghini R&D's question: what does downsizing mean In technical literature downsizing is often referred to as reducing displacement and, sometimes, cylinders. Through a methodological approach, analysis and experimental activities Automobili Lamborghini, with FEV's support, shows that downsizing in terms of engine friction reduction means only reduction of displacement. Using the Aventador V12 6.5 liter engine as a baseline, two 4.3 liter engines were designed, a V8 and a V12. The engine friction losses of these two engines were calculated all over the engine speed range and during the NEDC cycle utilizing a simulation tool and verified through FEV's “Strip-Method” database. This approach gives us the holistic understanding on engine components design and which technologies should be introduced for the next Lamborghini engine generation.

Downsizing in combination with turbocharging currently represents the main technology trend for meeting CO2 emissions with gasoline engines. Besides the well-known advantages of downsizing the compression ratio has to be reduced in order to mitigate knock at higher engine loads along with increased turbocharging demand to compensate for the reduction in power. Another disadvantage occurs at part load with increasing boost pressure levels causing the part load efficiencies to deteriorate. The application of a variable compression ratio (VCR) system can help to mitigate these disadvantages. The 2-stage VCR system with variable kinetic lengths entails variable powertrain components which can be used instead of the conventional components and thus only require minor modifications for existing engine architectures. The presented variable length connecting rod system has been continuously developed over the past years.

The loads on the plain bearings of modern combustion engines increase continuously. Reasons for this development are increasing engine speeds on gasoline engines, growing cylinder peak pressures at diesel engines and both combined with the steady trend toward light weight concepts. The still significantly increasing power output of modern engines has to be combined with actions reducing the engine friction losses, as for example smaller bearing dimensions or lower engine oil viscosities. At the same time the comfort, lifetime and engine service interval targets are aggravating boundary conditions. This development leads to the point, where former approaches toward plain bearing layout reach their systematic limitations - a first indication are bearing failures, which occur even though all conventional layout criteria's are fulfilled. Further effects need to be considered to simulate the behavior of the plain bearing under the boundary conditions of a fired combustion engine.