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Gasoline engine downsizing is already established as a proven technology to reduce automotive fleet CO₂ emissions. Further real-world benefits are possible through more aggressive downsizing; however, there is a trade-off between maintaining a high compression ratio for good part load fuel consumption and maintaining optimal combustion phasing at higher loads. There are many different technologies, which could be applied to gasoline-downsized engines in order to improve efficiency. One is to adopt a Miller/Atkinson cycle, which uses variable valve timing to reduce throttling losses in part load operation and reduce effective compression ratio to optimize combustion phasing at higher loads. MAHLE Intake CamInCam® is a technology enabler for Miller/Atkinson cycle operation. It uses asymmetric intake valve timing control to effectively provide a method of running increased intake cam duration allowing Late Intake Valve Closing cycle strategies to be adopted.

Emissions legislation, fleet CO₂ targets and customer demands are driving the requirements for reducing fuel consumption. This is being achieved in the gasoline market in the near term through the adoption of engine downsizing. In order to reduce fuel consumption further and in the wider real-world operating region complimentary technologies are being investigated and applied to an extreme downsized engine. In this paper future gasoline engine technologies are applied and experimentally assessed in terms of fuel consumption improvement whilst the impact of subsequent loadings on the thermal management system have been simulated, both over drive cycle and using real-world drive data.