Wankels

Wankels, in common usage, refer to Wankel engines, a family of rotary internal combustion engines named after German engineer Felix Wankel. Instead of pistons, the engine uses a roughly triangular rotor that orbits in a specially shaped housing, creating three rotating chambers whose volumes change as the rotor moves. Combustion occurs in these chambers, producing a continuous rotary motion with fewer moving parts than a piston engine.

Development and adoption: Felix Wankel and engineers at NSU Motorenwerke developed the concept in the 1950s. NSU introduced the first production car with a Wankel engine, the Ro 80, in 1967. Mazda became a major developer of Wankel technology, launching the Cosmo Sport in 1967 and later the RX‑7 and RX‑8. The technology was praised for a compact package and high-revving capability but faced ongoing challenges with sealing, fuel economy, and emissions.

Characteristics: Advantages include a high power-to-weight ratio, compact footprint, and smooth operation at high rpm due to the rotary motion. Disadvantages include higher oil consumption, greater thermal management demands, and apex-seal and side-seal wear, which can affect reliability and maintenance. Precision manufacturing and careful sealing are important to sustain performance and longevity.

Legacy and current status: Wankel engines remain in use in some niche automotive applications and concept vehicles, and are studied in research settings for potential uses such as range extenders or aviation powerplants. Mazda’s mass-market use has diminished, but the rotary engine remains a notable chapter in automotive history and engine research.