Sports cars are fast and fun. Truth be told, they're also usually a purely selfish indulgence. Their powerful engines are often gas-guzzlers, less than friendly to the environment. And they're typically two-seaters, making them of little use to friends and/or family who may be longing to come along for the ride. Mazda has created a kinder, more generous sort of sports car. The Concept RX-8, the company's thinly veiled future flagship vehicle, seats four and boasts an engine that's both powerful and fuel-efficient.

Powering the RX-8 is a 1.3-liter 250-horsepower rotary engine. Mazda has had 40 years of experience producing rotaries and is the only manufacturer in the world that offers a pure rotational internal combustion engine. The RX-8's engine -- dubbed the Renesis -- is a new type of rotary, similar to the one that was offered in Mazda's RX-7 (last sold here in 1995), but with a few significant improvements. It makes almost as much power as the RX-7's turbocharged engine (with power levels up to 250 horsepower at 8,500 rpm), but is 30 percent lighter and more compact. Unlike previous rotaries, which used side exhaust ports and peripheral intake ports, the naturally aspirated Renesis has intake and exhaust ports in the side housings; this configuration eliminates overlap between the opening of the intake and exhaust ports, improving combustion efficiency and permitting the engine enhanced fuel economy and reduced emissions. And compared to the RX-7's rotary, the engine's intake ports open sooner, and its exhaust ports open later, resulting in a longer power stroke and improved heat efficiency. Backing the Renesis is a six-speed automanual transmission.

The fact that the Renesis is not as tall as other rotaries brings with it significant advantages when it comes to the RX-8's overall layout. At about the same height as the transmission, the engine's bantam stature allows it to be mounted near the center of the body -- 60 millimeters closer to the center than in an RX-7 -- helping the car to achieve 50/50 front/rear weight distribution. Additionally, its compactness plays a part in enabling the RX-8 to offer sedan-size cabin space without compromising its low-slung sports-car lines. "The use of a compact rotary engine allows for the low hood, short overhangs and overall sports car look, while providing interior room on par with a sport sedan," says Kei Kado, Mazda's senior managing director in charge of R&D and Quality Assurance. The engine's weight, size, low center of gravity and positioning also work to enhance the car's maneuverability and performance.

Scrutinize the RX-8's doors, and you'll see that the car offers something new in this area, as well. The sedan boasts an unusual freestyle door system, with no center pillar; doors are front- and rear-hinged, making rear-seat ingress and egress faster and easier.

The RX-8 features a double-wishbone suspension at all four corners. The upper and lower arms in both the front and rear are considerably longer than those on the RX-7, allowing for consistent grip regardless of changes in roll and camber, and providing a smooth roll center and top-notch cornering performance. Additionally, the car's rear suspension springs are positioned lower than usual, giving the car more trunk space than your typical sports car.

Buyers deserve the opportunity to own the ingenious RX-8, and Mazda seems determined to make this concept car a reality. "With its four-door freestyle door system, four-passenger comfort and Renesis rotary engine, the Mazda RX-8 is the next big thing in sports cars," says Mazda President Mark Fields. "I wouldn't be surprised if you see this car -- or something very close -- on some of the world's most scenic, fun-to-drive highways in the not-so-distant future."