This piece is designed for cars that don't have a tach feed that can be used for Shift lights, Rpm inputs, High Performance ignition systems, Apexi Super AFC's, and other devices that need a tachometer input. This piece wires into the leads that run to the coilpack, and give a clean tach output signal. Four wires to connect/solder. Manufacturers info: MSD distributorless ignition tachometer adapters allow you to install an aftermarket tachometer on vehicles with no distributor and multiple coil packs. These compact tach drivers measure only 1.5"x 3.5"x 2" and are potted with a polyurethane compound for vibration and water protection so it can easily be mounted under the hood. It wires inline on the coils' 12 volt supply wire where it senses the current going through the wire and converts this information into a 12 volt output signal that most aftermarket tachometers use as a trigger signal. MSD distributorless ignition tachometer adapters can be used on 4, 6 or 8-cylinder engines.
