Mazda is cutting the advertised horsepower figure for its crucial new rotary-engine-powered RX-8 sports car in the United States, according to WardsAuto.com. A Mazda spokesman told WardsAuto.com that the new, four-door RX-8, powered by the company's signature engine that uses trochoid-shaped rotors instead of conventional pistons, makes slightly less power than originally billed - the higher-power version of the rotary produces 238 hp rather than the 247 hp Mazda originally specified while the lower-power rotary, sold with automatic transmission, develops 197 hp instead of the 207 hp Mazda first indicated.