The Davis Technologies Digital Timing Retarder (DTR) adds a 0-5 volt referenced timing retarder to ignition systems that do not otherwise have them. This small, lightweight device provides very precise timing control to allow our line of patented traction control units to interface with most ignition systems. Various configurations allow easy “Plug-N-Play” connection to the existing wiring with minimal effort. Easily adjusted with rotary dials, and an bi-color LED make this unit simple to use. Timing retard range from 0-20 degrees on the 0-5 volt input. The DTR also includes an adjustable Step Retard from 0-20 degrees activated by a 12v ON/Off input. An analog output is also provided to allow connection to a data acquisition system so that timing changes can be logged. There are a few different variations of the DTR to allow triggering from many different sources. The DTR-3000 is triggered with a 12 volt square wave (points trigger). The DTR-3000-VR is triggered by a variable reluctance (crank trigger) input. The DTR-3000-PG is prewired for use with a MSD® Power Grid® system, and the DTR-3000-6S is specifically designed for use with the MSD® Six Shooter®.