Ignition Systems

Here’s a largely misunderstood part. The Vacuum Operated Electric Switch (V.O.E.S.) was standard equipment on all Evolution® engines and works in conjunction with most all late model electronic ignitions, both factory and aftermarket. It senses high and low manifold vacuum and signals the ignition to change its advance slope. Under high load, the switch signals the ignition module to electronically retard ignition timing to reduce the possibility of detonation. In low-load conditions such as cruising at light throttle, the ignition stays in the advanced mode for increased fuel economy and lower operating temperature. All controlled by the magical V.O.E.S. switch! Available with the switch activation pre-set to operate at 4, 5 or 6” of Mercury for your calibration requirements. If your pre-Twin Cam® engine doesn’t have one, it should.