The function of the fuel supply system in the spark-ignition engine is simple: to supply the correct volume of fuel at the correct pressure appropriate to the method of engine fuelling used. In the case of a carburettor, for instance, this might mean a fuel pressure of no more than 1.5-2 psi (10-15 kPa) pumping the fuel into the carburettor float chamber, from which the fuel will be sucked into the intake air stream. A simple, engine mounted, cam-actuated mechanical lift pump using an...