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A new generation of gasoline engine turbochargers has been developed with a focus on high performance and excellent NVH characteristics, especially with regards to the wastegate control system. With the recent introduction of EU6 emission standards, there is a clear demand to precisely control the flow of exhaust gas through the turbine wastegate. Engine operational duty cycles measured on EU6 compatible vehicles have shown increased stresses on wastegate parts due to a higher amount of regulation strokes during operation. Recent developments in the compact design of exhaust systems together with high pressure pulsation forces acting on wastegate flaps constitute the main challenges facing turbo engineers in the effort to achieve customer durability while meeting NVH requirements. For the development of a new generation of wastegate control systems a unique load prediction model was duly developed.

As emission regulations tighten across various regions of the world there is a growing trend in the use of alternative fuels such as Ethanol being blended with gasoline. A notable case of Ethanol usage is found in South America with the widespread use of E100, which has no gasoline content and can often contain up to 10% water. Engine oil contamination by fuel is of major concern and under certain conditions can have negative effects on the durability of turbocharger components which come into contact with contaminated oil, particularly sliding bearings, but also compressor stage through crankcase ventilation system fed gas. The manner in which this effect takes hold can cause a decrease in the lubrication properties and increase in corrosiveness of the engine oil.