Compression ratio, gasoline

Eor a considerable period, >90% of the new cars in Brazil operated on E96 fuel, or a mixture of 96% ethanol and 4% water (82). The engines have high compression ratios (ca 12 1) to utilize the high knock resistance of ethanol and deUver optimum fuel economy. In 1989 more than one-third of Brazil s 10 million automobiles operated on 96% ethanol/4% water fuel. The remainder ran on gasoline blends containing up to 20% ethanol (5). 

The diesel engine operates with a much higher compression ratio (CR) than does a gasoline engine, and therefore is manufactured with structurally... 

The best efficiency attainable from a gasoline engine of specified power rating depends heavily on four parameters compression ratio, air/fuel ratio, spark timing, and the fraction of the mechanical energy developed in the cylinder or cylinders devot-... 

Jerome O. Nriagu. The Rise and Fall of Leaded Gasoline. The Science of the Total Environment. 92 (1990) 13-28. An authoritative history of leaded gasoline. The source for airplane octane lead industry pays Kehoe s salary one of few environmentally unsafe products forced out of market place one of top 10 chemicals in U.S. Esso slogan compression ratio and valve seat recession Kettering about automobile at crossroads, Europe versus U.S. 90 percent all U.S. gas and 80 percent worldwide autos after 20 years of TEL TEL drove U.S. transport lead removed from Ethyl trade name and Ethyl s control of publications and environment to be monitored by voluntary self-regulation, not legislation. 

The thermodynamic cycle for hydrogen is much closer to the ideal Otto cycle than for either a gasoline or a diesel engine. In addition, the compression ratio can be higher. 

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