MSD Automatic Coil Selectors

MSD automatic coil selectors are quick and easy way to switch from your primary ignition to your backup! Running two ignition systems gives you peace of mind during a long race, but how do you swap the coil wire to the back-up ignition? With MSD, that's how! They have two posts that connect to the voltage towers of the coils, while a third post connects to the distributor. When you switch to the back-up ignition, the coil selectors sense which coil is being fired and then transfer that coil's voltage to the distributor cap.