Gasoline Engine Economy-A European Viewpoint

This paper gives background data on gasoline utilisation and the present status of fuel consumption procedures in Europe. The relationships between octane number requirement, compression ratio, and fuel consumption from current British cars of 1.0 to 4.0-litre capacity have been analysed. Published data are compared with results from dynamometer tests of engines and vehicles over a range of compression ratios.

Various vehicle operating cycles have been used to show the consistently adverse effect on fuel consumption of lowering compression ratio, regardless of operating conditions. Gear ratio effects were also examined, and consumption trends were found to be dependent on the operating cycle.

An amalgamation of all results gives an economy relationship for European cars similar to that shown for American automobiles - 1.4% more fuel used per unit drop in octane number.