Abstract: The invention relates to an improvement in an engine fuel pump having a fill port in a plunger closed and opened during plunger strokes by a face of a relatively stationary barrel surrounding the plunger. A spill port in the plunger is closed and opened during plunger strokes by a relatively stationary collar surrounding the plunger and a linkage structure is operable by a governor or the like for adjusting the collar axially on the plunger to vary the separation of the barrel face from the collar and thereby the volume of fuel delivered per plunger stroke. The improvement of the invention comprises an oblique surface serving as the barrel face along with apparatus for adjustably setting the angular position of the plunger about its axes and thereby adjusting injection timing.