Right from the start, Audi never had the slightest doubt that quattro was perfectly suited to motorsport. Audi entered the World Rally Championship in 1981 and was exceedingly successful.
Then race cars equipped with permanent all-wheel drive dominated every circuit racing competition they entered. The successes: 1988 in the North American TransAm series with the Audi 200 turbo quattro, the first oval track car in Audi history; 1989 in the most challenging touring car series in North America, the IMSA GTO, with the Audi 90 quattro IMSA GTO; 1990 in the German Touring Car Masters (DTM) with the Audi V8 quattro DTM; and 1996 in the Super Touring Car Cup (STW) and in six other international championships with the Audi A4 quattro Supertouring.
With its success in racing, quattro technology shaped the image of the Audi brand in a more enduring fashion than any advertising campaign costing millions ever could.
The Rally quattro
The idea of a rally car was every bit as old as the concept for the production car at Audi, originating in 1977. The Audi Sport Department was established the following year and became involved in rally racing with the front-wheel drive Audi 80.
The first quattro ran as a course car in the European Championship series race in Portugal. In early 1981, the quattro cars swept over the rally scene like a force of nature. Local driver Franz Wittmann won the Janner Rally in Austria, which was not a World Championship race, in a Rally quattro with a lead of more than 20 minutes over the second-place car.
The Rally quattro used the same five-cylinder turbo as the production car; the 10-cylinder engine developed a hearty 230 kW (roughly 310 hp) from 2.1 liters of displacement and 1.6 bar of boost. Lightweight body components limited its weight to around 1,200 kilograms (2,645.55 lb), roughly 100 kilograms (220.46 lb) less than the production car. Depending on the final drive ratio, the Rally quattro accelerated from 0 to 100 km/h (0 to 62.14 mph) in around 5.2 seconds on a dry surface.
At its World Championship debut in the Monte Carlo Rally, the quattro again demonstrated its superiority. Ten kilometers into the first stage, Hannu Mikkola passed a Lancia Stratos in the snow that had started one minute before him; only an accident was able to slow the Finn. Then, in the Swedish Rally, he clinched the first win. The French driver Michèle Mouton became the first woman to win a World Championship race in San Remo, and Mikkola emerged victorious again in the RAC Rally. At the end of the Audi model’s first year in action, it was placed third in the drivers’ standings.
By 1982, the quattro was already virtually unbeatable anywhere in the world; Audi easily captured the Manufacturers’ Trophy with seven victories. Mouton won in Portugal, Greece and Brazil; only a breakdown in the penultimate race in the Ivory Coast cost her the drivers’ title. However, Mikkola became champion in 1983 after winning in Finland, Sweden, Argentina and Portugal.
Audi introduced two evolutions of the competition car in quick succession during this season. The second version with the internal designation A2 ultimately developed as much as 295 kW (a good 400 hp). The weight was reduced to less than 1,100 kilograms (2,425.08 lb), in part due to an aluminum cylinder block.
The next year, too, began with a win. The newly recruited double world champion Walter Röhrl won the Monte Carlo Rally ahead of his team colleagues Stig Blomqvist (Sweden) and Hannu Mikkola. The season ended with Audi once again dominating the manufacturers’ championship with seven victories. Blomqvist posted five of those and won the drivers’ championship ahead of Mikkola.
The Sport quattro S1
Rally racing reached new heights in the 1984 season. The competitors exploited the very liberal regulations at that time in Group B to enter mid-engine cars that were pure race cars with only a visual resemblance to production models. Audi also considered a similar concept. A prototype was developed but then put back on ice.
Audi’s new weapon was the Sport quattro with a wheelbase of just 2,224 millimeters (7.30 ft) – an attempt to make the near-series front-engine concept lighter and more maneuverable by shortening it drastically by 300 millimeters (11.81 in). The “short” quattro raced from May in parallel with the Rally quattro A2, but took time to build up some momentum. Blomqvist had to wait until the penultimate race in the Ivory Coast for the first win. Audi needed to turn up the heat.
July 1, 1985 was the date of the homologation of the final stage in its evolution, the S1. The aluminum five-cylinder engine with 20 valves officially developed 350 kW (476 hp) and 480 Nm (354.03 lb ft) of torque; with a charge-air circulation system that kept the turbo engine constantly under boost, the actual figure was probably in excess of 370 kW (over 500 hp), at around 8,000 rpm. In the middle ratio the 1,090 kilogram (2,403.04 lb) S1 shot from 0 to 100 km/h (62.14 mph) in 3.1 seconds, and to 200 km/h (124.27 mph) in 11.8 seconds.
There were various differential locks to choose from for the quattro powertrain – multi-plate, Torsen and conventional. In the last race of the season, the British RAC Rally, Walter Röhrl used a dual-clutch transmission that was actuated pneumatically – a precursor of today’s S tronic. The chassis comprised a tubular space frame paneled with sheet steel and plastic; to optimize the weight distribution the radiator, fan, battery and alternator were at the rear. Large wings generated downforce on fast sections of the course.
Röhrl meticulously fine-tuned the S1 over a period of weeks in Liguria. At the San Remo Rally in October, he won 29 of the 45 stages and crossed the finish line as the winner with a lead of 6:29 minutes.
The powder keg days of Group B were numbered, however. The final blow came in spring 1986 when several spectators and participants were killed in accidents at World Championship races in Portugal and Corsica. Audi withdrew from the series, and FISA, the world governing body, approved the changeover to the near-series Group A rules. The new mid-engine car from Ingolstadt was never raced.
The S1 Pikes Peak
Following the end of Group B, the S1 was still able to celebrate one last triumph – victory in the 1987 Pikes Peak mountain race with Walter Röhrl at the wheel.
The “International Hill Climb” on the 4,301 meter (14,110 ft) mountain in the U.S. state of Colorado takes place at dizzying heights. The starting line at 2,866 meters (9,400 ft) and the finish line is at the summit 19.99 kilometers (12.42 miles) away. At that time, the serpentine course with its 156 curves consisted mainly of sand and gravel over a solid substrate of clay. The course is six meters (19.69 ft) wide on the straights and up to 15 meters (49.21 ft) wide in the corners; there are no guardrails. The course repeatedly runs along sharp edges like the edge of a table. At a point known as the “Bottomless Pit,” there is a gaping 1,800 meter (5,900 ft) drop-off.
Audi entered the Pikes Peak race for the first time in 1984. Michèle Mouton finished second in the Sport quattro; she won the race in 1985. In 1986, local driver Bobby Unser set a new record of 11:09.22 minutes in the S1; Walter Röhrl followed him the next year. His Sport quattro S1 was a concept of bare functionality pushed to the absolute limit. The five-cylinder engine pumped out 440 kW (nearly 600 hp) and 590 Nm (435.16 lb-ft) of torque. The recirculation system kept the large turbocharger spinning. A dual-clutch transmission directed the power to a quattro powertrain with three locking differentials.
Sitting behind the 16-inch tires with the cut slicks was a small and lightweight brake system developed specifically for hill climbs. The S1 weighed only around 1,000 kilograms (2,200 lb) and featured a tubular space frame paneled with steel and plastic. Massive wings at the front and rear pressed the body against the ground, and even the flanks sported vertical stabilizers.
On race day, June 11, Röhrl started second to last, before the driver with the fastest practice time, Ari Vatanen (Peugeot). As calm and collected as ever behind the wheel, the Bavarian navigated the world’s highest highway in the record time of 10:47.85 minutes. He got the Sport quattro S1 into sixth gear four times and was clocked at 196 km/h (121.79 mph) at the fastest part of the track. Röhrl beat Vatanen by nearly seven seconds.