Growing up as a math and science nerd in the early '70s in a blue-collar Maine town, I had only one socially acceptable outlet for my abnormal interest in all things technical: cars. While my brother played baseball down the street, I stayed at home building a plastic model of Mazda's Japanese-built , dubbed the "engine of the future" in magazine articles of the day. As an 11-year-old, I didn't have the model-building experience to get my battery-powered model to run properly. But years later, when I looked at it again, I saw the obvious mistake I'd made wiring the thing together, and I finally got its plastic guts spinning.
Mazda seems to have had a similar experience with its real-life engine. The company began building rotary-powered cars in 1967, and its rotary-powered sports car, the RX-7, introduced in 1977, proved lighter and faster than many pricier hot rods with more complex, heavy engines. Based on a design by German inventor Felix Wankel, the engine held a pair of spinning triangular rotors, rather than the pumping pistons that have powered most automobiles since their Piston engines rely on a Rube Goldberg array of valves, levers, camshafts, belts, and pumps to feed fuel into their combustion chambers and whisk away the exhaust. The whole idea of converting the jerky up-and-down motion of a V-shaped array of pistons under the hood into a smooth spin at the rear wheels seemed wrong from the start. By contrast, my Wankel model had only three moving parts inside the engine: two triangular rotors spinning gracefully about a central driveshaft. The design was said to be simple, reliable, and powerful for its size. You can demonstrate the basic principle for yourself by taking a ring from your finger and placing it over a pencil. Hold the pencil in front of you between your hands and twirl it. The ring will orbit the pencil, tracing a spirographlike circle in the air. The Wankel design works like that in reverse: The orbiting rotor spins the driveshaft at its center.
