Mazda RX-7 R2

157 MPHToyota Supra TurboI magine: Blasting down the desert test venue, you shift to fifth at 120 mph in the Supra Turbo. Little more than a path, the lane is lined with unyielding bush-topped dirt moguls and gnarled scrub trees. Gravel shoulders narrow the road's useful width to 17 feet, sometimes less. Crosswinds and bumps start to make the car wander as you grab sixth at 150 and flash by a car-width away from our half-course marshal in a parked vehicle. Suddenly, boom!, the Supra lurches and the engine sound falls off. Has the motor blown, dumping oil on the tires? Are you about to pirouette across the desert? Will this make CNN? Nope, it's just the Toyota Supra Turbo smacking into its speed limiter. Its computer is supposed to restrict it to 155 mph, but the car is accelerating so hard it balloons past the fuel cut-off point, before falling back and making another charge toward forbidden ground. With its sleek shape and 3.0-liter DOHC inline-six force-fed by twin-sequential turbochargers pumping out 320 horses, it's likely an unrestricted Supra would roar past 165 mph.

160 MPHMazda RX-7 R2Twenty-five years ago, some automotive prognosticators tapped the rotary engine to displace piston powerplants. This unique engine, powered by two triangular rotors spinning inside an oval housing, is smaller, lighter, and, with a few exceptions, more durable than a comparably powerful piston engine. But its emissions were, at first, more difficult to cleanse, and it got a bad reputation for being thirsty. Today, only the Mazda RX-7 employs a rotary engine, but it shines gloriously. First, the RX-7's twin-turbocharged 1.3-liter rotary makes almost as much horsepower as the Z28's naturally aspirated 5.7-liter V-8. Also, the svelte rotary helps the RX-7 maintain a 950-pound lower weight and slimmer shape than the 3000GT VR-4, allowing the Mazda, despite giving away 65 horses, to beat the flagship Mitsubishi in virtually every performance parameter, including top speed. The R2's stiff suspension, however, interacted with our bumpy test road to make the RX-7 uncomfortably darty at its 160-mph peak velocity.