<NSU RO80

Introduction

Development of the RO80 began in 1961 under the watchful eye of Chief stylist was Claus Luthe, with the car being officially shown six years later at the 1967 Frankfurt Auto Show. The twin-rotor four-stroke motor was developed by German Dr. Felix Wankel. Considerably lighter and smaller than conventional piston engines, it was also famous for its turbine-smooth operation.

Running on low-quality fuel, and with general dimensions of a two-litre sedan, the shapely RO80 demonstrated it was capable of speeds exceeding 112 miles per hour and of accelerating from 0 to 60 miles per hour in 12½ seconds - in spite of an inevitable power loss through the torque converter.

The power-curve had been cleverly matched with the torque converter and with the gear ratios to provide liveliness of a high order, and engine characteristics at anything over 1,000 rpm were akin to a turbine.

The engine length was only 21½ inches and a long wheelbase of 9 ft. 4½ in., combined to provide generous internal space, although the fuel tank behind the rear seat somewhat nullified the advantage.

Weighing only 265 lb., the Wankel engine was only two-thirds the weight of a comparable piston unit, and about half the size. To foster faith in the unconventional power-plant, NSU guaranteed its life for 18 months or 18,000 miles, which was at the time a considerable improvement over normal warranty periods.

There were two coils, two spark plugs to each combustion chamber, and two double-choke compound Solex carburetters. Fuel consumption under give-and-take conditions was around 25 mpg (Imp.). The engine was water-cooled with a thermostat in the system as well as a viscous drive cooling fan.

In spite of a 63/37 (front-rear) weight distribution, the Ro80 handled extremely well, and displayed no vicious change from under to oversteer when the throttle was closed, and the servo-assisted four wheel disc brake system worked admirably. Front suspension was by McPherson strut and coil springs, and at the rear by semi-trailing wishbones and coil springs.

With a semi-automatic gearbox with torque converter, front-wheel drive, all-independent suspension, four wheel disc brakes with dual safety circuits, impressive aerodynamics design(Cd 0.36) and a modern shape (looking more like a car of the 80's) the RO80 was well ahead of its time.

Development Notes

The NSU Ro80 was originally to have a two rotor engine with 2 x 300 cc capacity, however this was increased in size for the production of the vehicle to 2 x 497 cc. Though weight distribution was 63/37 front/rear the car handled very well. The Chief stylist was Claus Luthe. About 33,900 were produced, with a three rotor successor being readied for release in 1969, but about this time NSU was swallowed by Volkwagen / Audi. Political intrigue, financial pressures and conservatism at VW snuffed out rotary development.