- If you are connecting a tachometer to an MSD Ignition, or your application is equipped with electronic fuel injection then you may need to use this Tach/Fuel Injection Adapter to ensure correct operation. This Adapter will correct the operation of most tachometers and fuel injection pump relays that do not work directly off of the MSD Ignition’s 12 volt square wave tach output terminal.
If, after installing an MSD Ignition Control, your tachometer, fuel pump relay or electronic fuel injection (in foreign vehicles) doesn’t operate correctly, your application may require a Tach Adapter. This is due to the trigger signal not being strong enough to trigger both the MSD and the factory’s components.There are a few Tach Adapters available and for more information see pages 152 and 153. Each Adapter is simple to wire in and will have your MSD and vehicle firing away in no time! If you are using the magnetic pick-up input (green and violet wires) to trigger your MSD Ignition, you will need the PN 8920 Tach Adapter. The PN 8920 will correct the operation of most voltage-triggered tachometers that do not work directly off the tach output terminal of the MSD Control. This Adapter should also be used on current-triggered tachs (hooked in series with the ignition switch).