Understanding The Rotary Engine

The rotary engines have been strange since their beginning and Mazda eventually got rid of them because of their bad maintenance and short life time (about 40.000 miles).

Inside the rotary engines we find a single waisted chamber shaped like the number 8, inside it there’s a triangular shaped rotor and while it’s not completely true, the rotary name comes from its oval path that the rotor follows back and forth like an orbiting satellite, spinning as it goes.

The rotor has a toothed hole as its centre engages witha  fixed gear to guide it acurately on its wonky path around the chamber. A crankshaft through the center of the rotortakes the drive to the transmission, rotating three times for every rotation of the rotor.

As the rotor passes through the chamber it opens certain ports from which it takes air and exahust gas exits as they are opened and closed,not needing valves anymore. The movement of the rotor creates and squishes between it and the wall of the chamber, and the changing volume of the spaces allows air in, space for expanding gases during combustion and exahust gas to be expelled.

This engine might be the most hard-working combustion engine ever on a car like the Mazda RX-7 and RX-8. For example in a 4 stroke piston engine, each piston generates power only once in every four strokes and two revolutions in the crankshaft. In a rotary engine, each single rotor generates power once per crankshaft revolution.The most common format is the twin-rotor, generating power once every half revolution, matching the bangs per rev of a four-cylinder piston engine.

Technically if they work kind of the same they should match rpm’s right? Wrong ! Even though they might seem simillar, the mazda rotary engines are low capacity, high power engines and they must be operated at a higher rpm than usual as the 1.3 litre petrol rotary engine turbocharged could’ve had an output of about 276 hp. Notably, this was the world’s first volume-production sequential turbocharger system.

There are so many working things that we don’t understand and we might never understand and the rotary engine used in the older Mazda RX-7 and RX-8 and other models. Also known as the Wankel engine, pioneered by NSU and embraced by Mazda, It’s technically the same as the piston engine but the alternative with no reciprocating parts.

Cars that have used rotary engines.