These are custom built in our facility for your specific application . Easy retrofit , clearly marked wire identification and simplified plug-in connectors make it the best on the market today. Speed Rail can be used for combinations of Ignition and Knock sensor wiring and thermocouples. There are many combinations available to simplify your engine wiring. Thinking of upgrading your ignition system, this is the answer to a labor- saving retrofit and upgrade. Along with Speed rail, Kraft can supply a complete ignition system for your engine, from the power supply to the spark plugs.