Ignition Control System: Operation: CARBURETED: Notes
The Justy distributor is equipped with both vacuum and electrical advance. Electrical advance is constantly operative, and is controlled by Ignition Timing Unit (ITU). On all other models, distributors are equipped with vacuum advance only. Vacuum advance on both systems is controlled by engine vacuum. The Justy system is equipped with a dual-diaphragm advance unit. Intake manifold vacuum is applied to auxiliary side of distributor vacuum control unit during idle, low-load operation and deceleration in order to provide an advance angle.
Vacuum produced in advance port is applied to main diaphragm side in relation to opening angle of throttle valve. This main advance provides additional advance angle. See Fig 1 .