The Mazda RX-500 is bonkers even by concept car standards. It had a 491cc rotary engine revving to 14,000 RPM and made a whopping 247 horsepower. Welcome to Japan in 1970.
In 1991, a Day-Glo-colored Mazda beat Mercedes and Jaguar to win the 24 Hours of Le Mans, the only rotary-powered car to date achieving the feat. Come and listen to its mad shriek.