A device is disclosed for sensing the speed of an EMD 567/645/710 two-cycle diesel engine having a crankcase, electronic fuel injectors and an electronic control system for controlling the electronic fuel injectors. The device includes a spline shaft sized for insertion into the crankcase of the engine so that the spline shaft rotates with the engine, a gear operably secured to the spline shaft to rotate with the spline shaft and sized to rotate with the engine in a 1:1 ratio, and at least one electronic sensor located adjacent the gear to sense rotation of the gear. The at least one electronic sensor is connectable to the electronic control system to provide electronic signals to the electronic control system for determining when to inject fuel with the electronic fuel injectors. Also disclosed is a method for retrofitting the engine and a kit for retrofitting the engine.