Ultra boost for economy: Realizing a 60% downsized engine concept

The paper discusses Ultra Boost for Economy, a collaborative project part-funded by the Technology Strategy Board, the UK's innovation agency. 'Ultraboost' combines industry- and academia-wide expertise to demonstrate that it is possible to reduce engine capacity by 60% and still achieve the torque curve of a large naturally-aspirated engine, while encompassing the attributes necessary to employ such a concept in premium vehicles.In addition to achieving the torque curve of the Jaguar Land Rover 5.0 litre V8 engine, the main project target was to show that such a downsized engine could in itself provide a viable route to a 35% reduction in vehicle tailpipe CO2, with the target drive cycle being the New European Drive Cycle. In order to do this vehicle modelling was employed to set part load operating points representative of a target vehicle and to provide weighting factors for these points. The engine was sized by using the fuel consumption improvement targets while a series of specification steps, designed to ensure that the required full-load performance and driveability could be achieved, was followed. The intake port in particular was the subject of much effort, and data is presented showing its performance versus a current state-of-the-art production design.The use of a test-cell-based charging system, while the engine-mounted charging system was being developed and characterized in parallel, is discussed. This approach allowed development of the base engine and combustion system without the complicating effects of the charging system performance coming into play. Finally, data is presented comparing the performance of the engine in this guise with that when the engine-driven turbocharger was used, showing that the peak torque and power targets have already been met.