A pocket history: 30 years of Audi Quattro

Winter testing Volkswagen's Iltis jeep in 1977, Audi chassis engineer Jörg Bensinger quickly discovered that in slippery conditions the high-riding all-wheel drive could, despite its meager 75bhp (56kW), outperform the more powerful 170bhp (127kW) two-wheel drive Audi 80 sedan that was being driven alongside it. This got him to thinking -- surely a sporty all-wheel drive sedan with superior traction and cornering behaviour would be the perfect solution.

In cooperation with Audi's director of pre-development, Walther Treser and technical director, Dr Ferdinand Piëch, a project dubbed 'Development Order 262' very quickly led to the production of a prototype vehicle, internally referred to as 'A1'. The car, itself based on the Audi 80, featured a slightly elongated wheelbase fitted with MacPherson struts front and rear (the rear being the front set-up essentially rotated through 180-degrees) and a five-cylinder turbocharged petrol engine.

Trialing the vehicle in deep snow at Turracher Höhe, Austria in January 1978, it soon became clear that the traction provided by the A1's new all-wheel drive system was a winner. In May that year, the car was given the definitive go-ahead by Volkswagen Board of Management Chairman, Toni Schmücker, after his own drive across a saturated sloping field proved how effortlessly the car delivered grip in trying conditions.

But it wasn't all smooth sailing. Driving the car around inner-city Vienna, the wife of Volkswagen Development Director, Ernst Fiala, said the car felt tense on sharp bends, telling her husband the car "hops" through tight turns. The issue was that through bends, the car's front wheels described a slightly larger arc than the rear wheels, and thusly, needed to rotate faster. Given the prototype's configuration, its axles connected rigidly, this simply wasn't possible, and Audi engineers set about focusing on two primary objectives: the all-wheel drive was to remain permanent, but it had to function without a separate transfer case and second (front) prop shaft.

From necessity, the hollow shaft was born. Franz Tengler, Audi's head of transmission design, conceiving the idea that a hollow-drilled secondary shaft in the transmission, through which power flowed in two directions driving the cage of the manually lockable centre differential. The centre diff transmitted 50 per cent of the engine's power via the prop shaft to the rear axle, which in turn had its own differential lock, while the other 50 per cent was transferred to the front axle's differential along an output shaft rotating inside the hollow secondary shaft.

Virtually wind-up-free, the lightweight and compact design was also very efficient, ideally suiting the faster pace passenger cars rather than all-terrain vehicles and trucks. Furthermore, it was relatively inexpensive, a bonus for mass-produced vehicles.

The only issue now was deciding upon a name for the new car. One suggestion was 'Carat', an acronym of the German for "Coupe All-Wheel Drive Turbo". But it was Treser who had a better idea, and at the Geneva Motor Show in March of 1980, 'quattro' (Italian for 'four') was born.

The angular coupe was an instant sales hit, and with its permanent all-wheel drive and 147kW five-cylinder turbocharged engine, soon became a favourite in rally circles. The model won two World Rally Championship drivers' and manufacturers' titles between 1982 and 1984 by which time, circuit racing teams had also adopted the permanent all-wheel drive system. The car went on to win events and championships across Europe, Australia and the United States, including an exhilarating win at Colorado's Pikes Peak Hill Climb in 1987.

That first production model enjoyed 11 years of showroom success, some 11,452 units being built, and along the way, other models joined the quattro line-up to reflect Audi's principle of offering a quattro model in each car line. From 1982, five more all-wheel drive models were added to the range (Audi coupe, Audi 80/90 and Audi 100/200).

Various improvements were also made in that time, including the important introduction of a Torsen (an abbreviation of 'torque sensing') differential in 1987, the Torsen differential replacing the original manual differential lock with a worm gear. The transmission distributed the propulsive power continuously, as required, diverting up to 75 per cent of the torque to whichever pair of wheels achieved better grip.

From the early 1990's, quattro was available across an even more diverse range of vehicles including coupes, sedans and wagons, expanding its appeal and building even more sales momentum. From 1995, Audi also began to offer quattro with its diesel-powered offerings, culminating in the latest Q7 SUV which is available with a 500bhp (386kW) 6.0-litre V12 engine.

By 2009 Audi had produced almost 3.3 million quattro models, its global range including an impressive 126 all-wheel drive variants, and in Australia with the popularity of the SUV models, Audi's share of Quattro models has grown from 25 per cent in 2004 (955 of 3702 units) to almost 50 per cent last year (5558 of 11,310 units). Later this year, the next generation quattro model, the new high-performance Audi RS-5 will make its local debut.

Unveiled at this year's Geneva Motor Show, the RS-5 coupe features the latest evolution of quattro technology - quattro drive with crown gear centre differential and torque vectoring. The self-locking centre differential in the quattro driveline, positioned at the transmission output, distributes engine torque between the two axles in defined proportions.

The all-new Audi RS-5 will be available locally from October. Pricing and specification will be released closer to the launch.