Centrifugal Spark Advance Mechanism

Exploded View Of TFI Ignition System Distributor.:

The centrifugal advance mechanism varies the relationship of the reluctor (armature) to the stator assembly. The reluctor is mounted to the sleeve and plate assembly which rotates in relation to the distributor shaft. The rotation is a result of the centrifugal weights moving in response to engine RPM. The movement of the weights change the initial relationship of the reluctor to the stator assembly by rotating the sleeve and plate assembly ahead of its static position on the distributor shaft Fig. 2. This produces spark advance. The rate of movement of the weights is controlled by calibrated springs.