1930-01-01

Powerplant Economics - Piston Displacement versus Horsepower per Dollar 300004

AN ENDEAVOR is made herein by the author to prove by argument and charts based on data that the greatest result per dollar of car cost is obtained by the greatest piston displacement obtainable per dollar expended rather than by the greatest horsepower per dollar.
Maximum result per dollar is a major principle of economics, but horsepower per dollar and piston displacement per dollar are controversial economic fundamentals. The latter is declared to be the accepted principle in the low-price car field, and the author asserts that it should be accepted in the high-price field.
Price class controls the cost of the powerplant, and ingenuity of the engineering and manufacturing departments will control piston displacement. The trends in the different price classes as regards car weight, piston displacement, ratio of weight to piston displacement, and potential and actual performance in the items of economy, durability, acceleration and speed, are shown by charts and discussed.
Adverse effects resulting from the endeavor to increase horsepower per dollar by higher engine-speed are considered and contrasted with effects obtained by a program of seeking maximum piston displacement per dollar.
Rational economics is stated to be incorporated in the latter program because, unlike the program of horsepower per dollar, it does not exclude progress through cooperation of the manufacturing departments with the engineering department to obtain the maximum result per dollar. Possible manufacturing economies to be obtained through such cooperation, in ways outlined, may amount to enough to cover a reasonable increase in piston displacement and, in addition, result in a cleaning up of the engine design.

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