Corvairs sold more than 200,000 in each of its first six model years. Chevrolet claimed that the rear-engine design offered packaging and economy advantages, providing the car with a lower silhouette, flat passenger compartment floor, no need for power-assisted steering or brakes and improvements in ride quality, traction, and braking balance. The design also attracted customers of other makes, primarily imports. The Corvair stood out, with engineering different from other American offerings. It used GM's Z-body, with design and engineering that advanced the rear-engine, rear-wheel drive layout most recently brought back into the market by cars including the Tatra 77, Tucker Torpedo, Fiat 500, Porsche 356, Volkswagen Beetle, Renault Dauphine, Subaru 360, and NSU Prinz—and employed by the concurrent and short-lived Hino Contessa.