Engine downsizing
In the automotive industry, engine downsizing is the practice of utilizing smaller combustion engines over larger ones of the same power capacity when manufacturing vehicles. It is the result of car manufacturers attempting to provide more efficient vehicles that emit fewer emissions, often mandated by legislative standards. The term generally relates to traditional internal combustion engines powered by petrol or diesel. Many manufacturers are reducing engine displacement and the number of cylinders. By adding a forced aspiration device (turbocharger or supercharger) and direct injection technology, they provide a powerful engine with similar performance to a much larger engine , but with much improved efficiency and reduced carbon emissions. A smaller engine is also often lighter, so less overall energy is expended while driving. Reducing the number of cylinders also reduces the amount of friction in the engine, increasing the efficiency. Some observers have not been convinced by manufacturer's claims that reducing engine size provides a more efficient car. Some tests have shown that some downsize engines have lower fuel economy in everyday driving than the larger engines they replace. Recent research and progress. The University of Bath published research carried out by its Powertrain and Vehicle Research Centre  which demonstrated that it is possible to reduce engine capacity by 60% and still achieve the torque curve of a modern, large-capacity naturally-aspirated engine, while encompassing the attributes necessary to employ such a concept in premium vehicles. Reliability. In an Auto Bild investigation of a 1.0 EcoBoost Ford Focus having driven , no major issues were found surrounding the engine, with only 'minimal oil sweating between cylinder and block' being noticed. However, the turbocharged Audi 2.0 TFSI petrol engine has frequently been reported to suffer from more severe oil leakage around the cylinder seals, with up to 1 liter  of oil consumed per . Similar issues have been reported for Volkswagen Group 1.4 and 1.8 TFSI engines. According to a J.D. Power survey, downsize engines scored significantly lower in reliability than older engines.