Abstract: The specification discloses a method and apparatus forlaboratory testing of carburetors to determine the mass air flow rate and mass fuel flow rate through the carburetor at any desired test point by providing, in addition to the normally required systems, an improved manifold vacuum control system for producing a predetermined air flow at a given manifold vacuum, and an improved hood pressure control system which enables carburetor testing to take place at test points which correspond to different altitudes in which the carburetor may be used. In addition, by providing that these systems be computer controlled, the three-mode controllers normally associated with producing air flow and controlling hood pressure are replaced by a computer which provides output control signals corresponding to that which would be provided by three-mode controllers where the values of rate, reset and proportion are continuously and automatically changed to the optimum value for each test point.

Abstract: The specification discloses an improved method and apparatus for determining the time angle of a diesel engine which, in contrast to the present day method, is one which is fast, accurate, and can be readily used on a production line basis. There is disclosed a method and apparatus which, by the utilization of pulses of fixed angular frequency produced by an encoder, and counted between the moment the pressure in the injector line of the cylinder, whose timing angle you are measuring, reaches a predetermined pressure and the moment the piston in the same cylinder reaches top dead center, a number of pulses representing the timing angle of the engine is obtained, which can easily be converted into a reading of the timing angle.