Mechanical Octanes for Higher Efficiency

D. F. Caris; B. J. Mitchell; A. D. McDuffie; F. A. Wyczalek

doi:10.4271/560010

HIGHER compression ratios, the main key to better passenger-car engine efficiency, can be increased by two main factors: chemical and mechanical octane numbers. Although remarkable gains have been made in the former in recent years, the limits in improvements have about been reached. Thus the current emphasis on means of improving mechanical octane numbers.

The authors tell here of important experiments and developments in ignition control, valve timing, carburetion, engine-transmission relationship, and combusion-chamber design—the five factors most important in achieving mechanical octane numbers.

Presented also are 25-year charts of trends in passenger-car weight, length, horsepower, engine speed/car speed, compression ratio, acceleration time, fuel economy, and efficiency.

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Mechanical Octanes for Higher Efficiency 560010

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