A study of the effects of changes in gasoline composition is one area to explore in our effort to reduce tailpipe emissions from vehicles. However, affects on vehicle performances should also be considered from the perspective of practical useage.
In this paper, the influence of gasoline composition (aromatics),volatility, and MTBE blending on engine outlet and tailpipe emissions are discussed,in particular,forcusing on distillation properties which have a close relationship to driveability.
Under stable driving conditios and without a catalitic converter, the effects of gasoline volatility is small, while aromatics in gasoline affect exhaust HC and NOx emissions. MTBE has a leaning effect on the engine intake air/fuel mixture.
During a transient driving cycle, a high gasoline 50% distillation temperature causes poor driveability, as a result, HC emissions increase.