🔧 Mazda Wankel Rotary Engine (12A / 13B)
The Wankel rotary engine was invented by Felix Wankel and licensed to NSU, but it was Mazda who successfully commercialised it for mass production. The 10A debuted in the Cosmo 110S in 1967; the 12A replaced it in 1970; the 13B (with twin rotor housings enlarged to 1,308cc) powered the RX-7 SA22, RX-7 FB, and ultimately the RX-7 FD with twin turbochargers producing 255 hp. The RX-8 used the RENESIS 13B-MSP without turbocharging but with side-exhaust ports. Every Mazda rotary shares the same eccentric shaft geometry, apex seal concept, and peripheral porting philosophy.
Engine
Technical Specifications
| Type | Wankel Twin-Rotor Rotary (12A or 13B) |
|---|---|
| Displacement | 1,146 cc (12A) / 1,308 cc (13B) |
| Horsepower | 105 hp (12A NA) / 255 hp (13B-REW turbo, RX-7 FD) |
| Apex Seals | Carbon (12A) / Ceramic-coated (13B-REW) |
| Coolant | Water-cooled rotor housings, oil-cooled rotors |
| Advantage | No valves; smooth power delivery; compact dimensions |
| Manufacturer | Mazda Motor Corporation, Hiroshima, Japan |
| Msrp | $2,000–$8,000 (rebuilt) |