The Influence of Fuel Characteristics on Engine Acceleration

SELECTION of a method and development of apparatus enabling precise and detailed measurement of engine acceleration is discussed in the first portion of this paper, the latter portion of which is concerned with the experimental results thereby obtained.

Previous work on the influence of engine conditions on acceleration is generally substantiated. A method is described for approximately deriving the effective air-fuel ratio delivered to the cylinders during acceleration, practical applications are suggested, and limitations are discussed.

The effect of fuel volatility on engine acceleration was studied, using six fuels: Aviation gasoline; commercial gasoline; a blend composed of equal parts of the two; and three especially prepared fuels, all of which have equal 20 and 90-per cent points but differ widely at the 50-per cent point. It is shown that the relative values of these fuels for acceleration depend upon the amount of vaporization in the manifold.