Figure 9 The path of the rotor in the Wankel engine

1. Intake.
Fuel/air mixture is drawn into combustion chamber by revolving rotor through intake port (upper left). No valves or valve operating mechanism needed.		 Intake and Compression 2. Compression.
As rotor continues revolving, it reduces space in chamber containing fuel and air. This compresses mixture.
3. Ignition.
Fuel/air mixture now fully compressed. Leading spark plug fires. A split-second later, following plug fires to assure complete combustion.		 Ignition and Exhaust 4. Exhaust.
Exploding mixture drives rotor, providing power. Rotor then expels gases through exhaust port.

Figure 9 The path of the rotor in the Wankel engine