Spark Advance Vacuum Modulator (SAVM)

This modulator is a dual diaphragm regulating valve which controls vacuum to the distributor advance. When both manifold vacuum and ported vacuum are below the calibration point, the distributor vacuum advance receives manifold vacuum. When manifold vacuum increases, but ported vacuum is less than the calibration, the distributor vacuum advance receives vacuum. When both manifold and ported vacuum are above the calibration point, the distributor vacuum advance receives ported vacuum.

NOTE: Refer to the number stamped on the base of the switch or valve for calibrated switching or activation temperatures.