Sports cars are losing their image as mildly amusing poseurs and moving closer to the punch and duty of lightly detuned race cars. Mazda's completely redesigned and thoroughly exhilarating RX-7 is typical of that evolution. It is a car one pulls on like Nomex coveralls. Legs thread through a marginally narrower tunnel toward pedals that are bare metal, dimpled and drilled to provide maximum feel for sensitive soles. Even with two persons aboard, the snug seating and a broad center console give the driver a sense of being surrounded by a monocoque cocoon; of being alone and quite at home on the center line of heady turbocharged thrust. By no coincidence at all, showroom-fresh RX-7s--with little modification beyond safety and speed tweaks--are running this season's Bridgestone Supercar Championship, a seven-race national series that boldly attempts to restore weekend racing to its stock and relatively inexpensive roots. The RX-7 certainly deserves a place among the Porsche 911s and Corvettes of that series. This car accelerates quicker than a Ferrari Testarossa, and its top end is faster than the Nissan 300ZX Turbo. Yet those are only numbers and fractional separations. A thoroughbred race car, no matter the maneuver, must offer unremitting balance throughout its performance range. Suspensions must be built to track flat and with a minimum of computerized gimmickry, so that tires set broad patches against the road and grip like Velcro. Power must be an explosion and an instantaneous winner over weight; braking should be capable of taming triple-digit speeds without frying pads and flat-spotting tires, and steering must be a quick, precise extension of the driver's thought process. Above all, as with surfboards or stallions, there should be an unbreakable, confident bond between vehicle and driver. Such integrity of ride is certainly a most tangible asset of the RX-7. That ride comes in two versions. The base RX-7 is a touring version with slightly softer shocks and bushings and less aggressive tires. An additional $2,000 buys the stiffer R1--badged as such and wearing saucy front and rear spoilers. It comes with dual oil coolers, more competitive tires and shocks that on even rippled surfaces present a serious threat to anyone with older crowns on their molars. Purists, of course, insist that the RX-7 is not a sports car. It has a Wankel rotary engine, therefore innards that go around instead of up and down. No wire wheels. The RX-7 has a hard lid and some sprawling room behind the seats, and this kind of layout should make it a Grand Touring car. Those mustachioed precisians might like to note, however, that when bolted to a pair of sequential turbochargers, the rotary mechanicals of the RX-7extract a hefty 225 horsepower from a relatively puny 1.3-liter engine. The RX-7's power-to-weight ratio is superior to that of sports cars costing twice as much. It streaks through the quarter-mile pylons at 100 m.p.h. in 14 seconds. The estimated top speed is 158 m.p.h. So sports car or GT? Ketch or yawl? Ground or shredded sirloin for your steak tartare? It should matter to no one but the person indulging the preference. Visually, the RX-7 has the lean, free-flowing look of thin metal stretched around stiffeners, the trademark of any monocoque design where frame and body are one. This unibody construction seems to allow gentler curves and finer sculpturing that in the RX-7 smacks of C Group racers or some gun metal gray concept from Mercedes or Porsche. It is a low, beautifully proportioned car with five-spoke aluminum wheels, Le Mans side mirrors, a soft shape and a stance with a single snarl: I exist to bring a little humility to the life of everything else on the road. If it weren't for the vulgarity of pop-up headlights--an '80s habit that happily is diminishing--the shap of the RX-7 would be world class, day or night. This is, however, a vehicle of rather singular dimension. Although perfectly mannered, the RX-7 is restless as a commuter car. Unless your commute be Paris-Lyons. There is space for only two people, two overnight cases, two tennis rackets, two microwave dinners and precious little else in trunk that is only 6 cubic feet--less than half the boot room of a Ford Tempo. The air bag is on the driver's side only. And at a base price of $31,300, the RX-7 is fiscal eons removed from its introductory years, when it was a bargain at $8,000. Of course, the 1978 car was only 100 horsepower, and its then unrefined rotary engine went into automatic drool when passing a gas station. This 1993 car has quenched that thirst. The RX-7 has gone aerospace through a weight reduction program extending even to a whiskery dip stick and an 18-pound aluminum hood. This leaner Mazda is 600 pounds lighter than Chevrolet's Corvette and 700 pounds under Nissan's 300ZX. And now there are 255 horses pulling this featherweight. The interior--with leather-faced seats on the R1--curves and flows as well as the exterior. The steering wheel is a mite smaller than most and gives the leather doughnut feel of a Formula car. Instruments are analog and chrome-rimmed beneath an oversized cowl--another touch of the track. It has been established that performance and handling of the RX-7--save for slight lumps in acceleration apparently caused by hyperactive turbocharging--are simply as good as they get. It hurtles in any gear, even with automatic transmission. It has limits way beyond those of even excellent amateur drivers. And it will show the average motorist what this intangible zip of driving, this magic mating between pilot and machine on a winding road, is really all about. Add to all this the results of recent comparison testing by Car & Driver magazine. The RX-7 placed second by a very small margin behind the incomparable Nissan 300ZX Turbo. More significantly, the RX-7scored highest in braking, handling and ergonomics, finishing ahead of the stiff-upper Lotus Elan and the muscular, hairy-chested Corvette. It rated a perfect 10 in the category of fun driving. If the RX-7 does not become an Rx for success, blame the economy. Or maybe some lingering suspicion of rotary engines. But not the car as a performance package. 1993 Mazda RX-7 The Good Racer's edge in looks and performance. High on mechanical purity, low on gadgets. Fuel guzzling has evaporated. Snug, nimble, highly personal transportation. The Bad No longer a budget sports car. Acceleration snag from excitable turbos. The Ugly Not a bit of it. Cost Base: $31,300. As tested: $34,790 (includes performance handling package, leather-faced seats, a larm, cruise control, antilock brakes, driver's side air bag, five-speaker Bose sound system with CD, power sunroof, etc.). Engine 2-rotor, inline rotary engine with sequential, twin, intercooled turbochargers developing 225 horsepower. Type Rear-drive, front-engine, two-seater sports/GTcar. Performance 0-60 m.p.h., as tested, with 5-speed manual, 6 seconds. Top speed, manufacturer's estimate, 158 m.p.h. Fuel economy, EPA, city-highway, 17 and 25 m.p.g. Curb Weight 2,870 pounds.