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Three-way conversion catalysts systems which provide control of three emission components - hydrocarbons, carbon monoxide, and oxides of nitrogen - generally require the use of closed-loop feedback control of the air/fuel metering system to provide a near stoichiometric exhaust gas composition. As an alternate fuel such as ethyl-alcohol is added to gasoline, the stoichiometric air/fuel ratio is altered. Conventional air/fuel metering systems do not compensate for this change. This paper studies the ability of the Volvo closed-loop control fuel injection system, now in use on vehicles in the United States, to maintain the stoichiometric air/fuel mixture needed for optimum emission control and to compensate for the change in fuel stoichiometry encountered in gasoline/alternate fuel mixtures. The system was found to have the ability to completely compensate for gasoline/ethyl alcohol mixtures up to 30% ethyl alcohol with no loss in emission control.

This paper summarizes the results of both the preliminary studies and the initial cycle tests of a unique type of IC engine capable of operating in the absence of an atmosphere. This engine has been designed specifically for use in the general space program, and it is intended to satisfy requirements of high power to weight ratio, reliability, compactness, and short development time. The history of the en-engine's development is discussed together with problems encountered in the study. However, primary emphasis is on the recently conducted cycle tests.