Atypical Fuel Volatility Effects on Driveability, Emissions, and Fuel Economy of Stratified Charge and Conventionally Powered Vehicles

The effects of fuels having atypical distillation characteristics on the driveability, fuel economy, and emissions of vehicles equipped with a variety of power plants were studied. The power plants included conventional, stratified charge, port fuel injected, and lean-burn engines. The atypical distillation fuels reflect the effect of removing varying amounts of mid-range or front-end blending components from a typical commercial gasoline.

An index system was developed which allows a comparison of fuel effects across a fleet of vehicles differing substantially in terms of driveability, fuel economy, and emissions. Using this index system, the fleet average results show that emissions and fuel economy as well as driveability are depreciated with the extreme atypical fuels and that improved driveability can result in improved emissions and fuel economy.