For 4, 6, or 8-cylinder engines with a stock inductive or MSD ignition that can handle up to 1.5 amps (except #121-8957 for 1.5+ amps), these switches can perform a variety of functions, from turning on a bulb or solenoid to engaging an MSD Timing Computer at a certain RPM.
#121-8950
This switch has two activation wires: one to ground a circuit, the other to open a circuit. Simply plug in an RPM module, and wire the switch to the circuit you want to control. When the engine reaches your set RPM, the circuit activates and stays on until the RPM falls below the set amount.
#121-8957
This magneto switch is for activating circuits that require more than 1.5 amps. A 12-volt source is required.
#121-8956
This window switch has two RPM adjustments: one to activate a circuit, the other to deactivate the same circuit, which is great for shutting down nitrous before the engine's rev limit is reached.
#121-89561
This window switch shares the same features as #121-8956 except that it's for DIS ignitions.Note: Required RPM modules are sold separately