DETROIT – Mazda Motor Corp. continues exploring the future of its “zoom-zoom” design language with the Ryuga concept car, making its debut tomorrow at the 2007 North American International Auto Show.

The Ryuga follows the much-talked-about Nagare concept shown at the recent Los Angeles auto show and continues the auto maker’s exploration of flow as it relates to vehicle design.

Ryuga (ree-yoo-ga) means “gracious flow” in Japanese and Nagare (na-gah-reh) means “flow.”

Mazda’s Laurens van den Acker, general manager-Design Div., says the Ryuga is comparable to prêt-a-porter clothing, which is unique but ready-to-wear, while he likens the Nagare to haute couture fashion.

“Ryuga celebrates refined and controlled motion,” van den Acker says. “Nagare is a dream or an emotion that’s just beginning to take shape. The Ryuga extends that idea by adding definition.”

Unlike the Nagare, Mazda specifies powertrain and interior details for the Ryuga, indicating the show vehicle more closely resembles a production model.

A 2.5L flex-fuel engine, capable of running on a blend of gasoline and ethanol, or E85, is standard in the front-wheel-drive Ryuga and mated to a 6-speed automatic transmission.

Steer-by-wire technology also is employed. Mazda says the open-top steering wheel is highly sensitive to driver input.

The wedge-shaped coupe has wheels pushed to the corners, conveying stability and balance, the auto maker says.

Mazda’s Charge-Coupled Device cameras monitor space behind the car and in the vehicle’s blind spots.

Similar to the Nagare, the Ryuga has a windswept appearance, highlighted by carved lines in the vehicle’s sides that were inspired by the lines created by raked pebbles in Japanese dry gardens, Ryuga Chief Designer Yasushi Nakamuta says.

Also inspired by nature is the shape of the Ryuga’s headlamps, which Nakamuta says recall “morning dew dropping from bamboo leaves.”

The advanced headlamps’ light-emitting diode and fluorescent-tube technology will enable the use of the design in a near-future production model, he says.

The Ryuga’s chameleon-like body color – a mixture of yellow, red and blue – is said to represent hot lava.

Helping to convey motion are the 21-in. twisted wheel spokes, different on the Ryuga’s right and left sides. The trailing edge of the spokes have a hint of color to simulate gas-turbine blades, Nakamuta says.

Inside, the Ryuga’s 110.2-in. (280-cm) wheelbase accommodates four passengers, despite the vehicle being significantly shorter and lower than the current 4-passenger RX-8, Mazda says.

Two gullwing doors provide entry to the show vehicle. The cockpit features an experimental floating center cluster, allowing the driver to interact with the multi-function touch panel without taking his eyes off the road.

Engine and vehicle speed are presented in analog and digital formats on the same axis, Mazda says.

The Ryuga’s textured door trim continues the side-body design flow, as carved lines that start at the concept’s 5-point grille sweep rearward through interior surfaces.

Interior materials include leather; polished aluminum; and translucent plastic; creating a warm glow, the auto maker says.

cschweinsberg@wardsauto.com