Petrol Injection: Some Further Developments

Abstract

In this paper is described recent developments of a shuttle metering injection system, and details of the construction and operation of high-speed six- and eight-cylinder units are included. Accuracy in mixture control performance is stressed as an essential requirement of any injection system, and a description of a control giving automatic operation from cold starting and through the warm-up stages is given. An account is given of some aspects of the application of the system to a high performance six-cylinder engine, and includes details of air flow measuring technique, and manifold design and development for this class of engine. A description is included of the effect of mixture strength on fuel consumption and power output, where economy in the engine of a racing car is required, and combustion chamber and exhaust temperature variations with mixture strength are shown on graphs. It is concluded that on the engine referred to, injection can offer the advantage of an improved torque curve, or if needed, a worth-while gain of up to 10 per cent in economy over the carburettor at the same output.