Why Mazda Built The Three-Rotor 20B Engine (And Used It Just Once) 365daily.net January 14, 2026 We look at why Mazda introduced the three-rotor 20B Wankel rotary engine, and why it only ever saw service in the Cosmo coupe of the late 1980s. Â Continue Reading Previous: How&How reimagines Trellis as a ‘living blueprint’ for generational healthNext: Porsche Wants to Use a Drone to Show Drivers the Perfect Racing Line