The Little Engine That Could Why Mazda's RX-8 is the sports car for nerds. By Paul Boutin Posted Tuesday, Aug. 19, 2003, at 7:07 PM ET
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 rotary engine, 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 inception. 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.
But Mazda had to pull the plug a few years after a prestigious win at LeMans in 1991, when the rotary engine proved unable to keep up with ever-tightening emissions standards in the United States and elsewhere. Piston-engine makers, said to be on their way out in the '70s, got through the '90s by incorporating computers, alloys, and plastics into their designs to gradually wring out smog-belching inefficiencies and excess weight. Mazda killed the RX-7 in 1995 and went back to building practical, if uninspiring, family vehicles with traditional engines.
Today, with retro all the rage in auto design, it isn't too surprising to see Mazda back with a new rotary-powered sports car, the RX-8. What is surprising is the serious buzz the car has already built. The WaPo dubbed it "transcendental," and influential Automobile magazine compared it to "two cars in one": a Nissan 350Z plus a 3-Series BMW, bundled into a $27,000 package. But good luck trying to buy one at that price now. A day of dealer-hopping in and around the San Francisco Bay Area found sticker prices as high as $36,000. One salesman claimed he'd heard of buyers paying $45,000 for the privilege of getting the first one off the truck.
Mazda has done for the rotary when Detroit did for its sexiest asset, the V8. The company poured money into an R & D project to fix the rotary's pollution problems without killing its performance. Mazda engineers replaced the engine's rotors with new ones made from a much lighter alloy. To reduce the amount of burnt oil, they computerized the oil injectors that keep the rotors lubricated. They programmed smarter engine-management software for the whole system. Even the production lines were computerized, allowing more precise parts to be designed.
Computer control over both the engine's construction and operation brought a long-sought breakthrough: By moving the engine's exhaust ports around—in a way that, without computer-aided design and assembly, Felix Wankel couldn't have—Mazda engineers vastly improved the flow of combusting gases swirling through the engine. The new design both increased the Wankel's efficiency and eliminated the noxious backwash of exhaust that had flowed into the incoming mix of fuel and air. The change enabled the redesigned engine not only to limbo under the latest government smog limits but also to generate a whopping 247 horsepower from a 1.3 liter engine. That's power close to Infiniti's flagship G35 coupe from a motor smaller than the one in my old Honda Civic. The redesigned engine, dubbed RENESIS by Mazda marketers (think "renaissance" plus "genesis"), wowed auto journalists enough to whup BMW, Volkswagen, and Honda handily in the vote for this year's International Engine of the Year.
OK, great engine, but what's it like to drive? Marin Mazda dealer Ed Rossi, who's been selling cars since the RX-7's heyday, let me take a bright red RX-8 for a spin on a sunny Northern California morning this week. The car looks weird in photos but surprisingly attractive in the flesh: perky, cute, and right at home next to a 350Z or Chrysler Crossfire. Under the hood, the RENESIS engine takes up half as much space as a comparable six-cylinder job. It fits behind the car's front axle, balancing the RX-8's weight evenly across front and rear tires without intruding on the driver's feet.
Freed of excess pounds and overhanging length, the tiny RENESIS responded to the motion of my right foot on the pedal as tightly as an old Singer sewing machine, revving uninhibitedly up to 9,000 rpm before I needed to shift. That's 50 percent to 100 percent more rpm than most six- or eight-cylinder engines of comparable power. And unlike most of those engines, the rotary feels eager to rev higher and higher until you back off the gas. Pulling around a slower driver, I impatiently pressed my foot down an inch and was rewarded with a satisfying zzzzzzZZZZZZING as the whirring rotors yanked the car from 23 to 56 mph without a shrug, then dropped back just as quickly when Rossi interjected that I was zinging past both the speed limit and the local police radar trap.
Is the Wankel still "the engine of the future"? Not anymore. High-tech hot-rodders now look to all-electric motors that are more energy-efficient, less harsh on the environment, and less dependent on fossil fuels to run them (though a lot of America's electrical juice still comes from burning coal). But until electric cars get up to speed, Mazda's rotary provides a nerdy alternative to the aging piston engine. It lacks the muscular rumble and tire-shredding torque of a Dodge V10, but it has an I'm-different whirr that makes the Wankel-powered RX-8 seem smarter, if not faster, than other sports coupes. And it takes up half the under-the-hood space of its competitors. Cute, peppy, compact, different: Call it the Mac OS X of engines.
Paul Boutin is a Silicon Valley-based writer who also contributes to BusinessWeek and Engadget.