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Alcohols (both ethanol and methanol) have been recognized as alternative fuels to replace dwindling gasoline supplies. In previous studies, the alcohols have shown a potential for lowering the emissions of regulated species (hydrocarbons, carbon monoxide, oxides of nitrogen.) In order to assess three-way catalyst performance on alcohol fuels, three 1978 Ford Pintos have been retrofitted to run on neat methanol, fuel. Over 30,000 vehicle miles have been assumulated during an 18-month period. Driveability, fuel economy and emission histories (CVS-78) have been obtained. Regulated emissions levels of all vehicles were below 1983 United States Federal standards throughout 10,000 miles of operation on each vehicle. Aldehyde emissions were a factor of three higher for methanol operation than gasoline. The energy economies for highway and urban driving cycles on the two fuels were comparable. Catalytic system efficiency for both fuels were evaluated.

Residual-effected HCCI is investigated using a single-cylinder research engine equipped with fully-flexible variable valve actuation. Dilution limits are explored with various valve profiles in order to gain insight into the best way to use exhaust residual to achieve and control HCCI. The tests repeatedly point out the importance of delayed combustion phasing to reduce thermal losses and maximize efficiency. Combustion phasing is not significantly affected by charge in-cylinder residence time, but is strongly influenced by both the level of exhaust residual and by valve strategies that aim to affect homogeneity. Further dilution with air shows little promise for reaching lower loads, but does suggest that operation near the lean limit can maximize efficiency while minimizing NO and CO emissions.