MITSUBISHI Electronic Ignition Systems - Rotary Engine: Description

The Mitsubishi electronic ignition system used on the Mazda RX7 rotary engine is unique in that it has 2 sets of spark plugs (leading and trailing) with one set in the front rotor housing and one in the rear rotor housing. See Figure. There are also 2 ignition coils, 2 pick-up coils in the distributor, and 2 coil-to-distributor high tension wires.

There are 2 separate ignitors, mounted on a common base, one for leading side and one for the trailing side. Other system components include a battery, ignition switch, ignition control switches (water temperature, altitude, etc.), and various relays.

All models are equipped with an ignition control system and centrifugal advance mechanisms. All models have vacuum control units on both trailing and leading sides, except automatic transmission models which have no trailing vacuum control unit.