Petrol Injection in Germany

Abstract

An account is given of the development of the petrol-injection system in Germany, a subdivision having been made according to piston aero-engine, two-stroke automobile engine and four-stroke automobile engine. The increase in performance achieved in the piston aero-engine by the injection system is described. Experiments carried out during the past 10 years on the two-stroke engine have shown that the demands made on the injection equipment in regard to injection accuracy and working life can be met forthwith, but that the injection system makes demands on scavenging which differ from those of the carburettor. The attraction of petrol injection in the four-stroke automobile engine is represented chiefly by the gain in performance, the wider controllable speed range and the faultless acceleration over the entire speed range irrespective of the driving conditions. As a rule, the authors' company supply for all these engines the fuel-injection systems known in connection with Diesel injection, making allowance for the slight variations called for and irrespective of whether direct injection or manifold injection is used. Manifold injection points to ways and means of effecting economy in the injection method (pump and nozzle). The control problem is the most difficult problem in petrol injection, no matter whether direct injection or manifold injection is used, and it calls for intensive development. The success of petrol injection is decisively governed by a faultlessly functioning mixture control.