Audi Extend Quattro Range
MARCHING forward with the logo “Vorsprung durch Technik” (a leap Ahead through technology) Audi has now extended its quattro four-wheel drive range with new versions of the 200 turbo model, the 90 and the Coupe. All will be available on the British market, including the short wheelbase 300 bhp Quattro Sport for which 10 firm orders have been placed at between £50,000 and £60,000 apiece in left-hand-drive form.
The Audi range has now been simplified, if that is the right word, by making the 80 models the four-cylinder versions, the similar 90 models the five-cylinder range, while the 100 and 200 models are the executive class five-cylinder range. The Audi 90 quattro, therefore, is virtually a direct replacement for the former 80 quattro while the four-wheel drive Coupe and 200 models are innovations. A lower-case “q” is used for all except the turbocharged Coupe models which brought the name Quattro to prominence.
The 200 quattro becomes the flagship of Audi’s range, a £20,000-plus 4-wd machine with a 182 bhp turbocharged engine. When the 200 turbo was introduced earlier this year it was greatly admired for its comfort, spaciousness and quietness, but there were reservations about putting all that power through the steered wheels. Even in the monsoon conditions that met as in Austria B the new model’s launch the 200 quattro never put a wheel wrong, accelerating hard on flooded roads, and out of corners, without any feeling of instability in the steering system.
Some fundamental changes were needed to drive the rear wheels, and Audi are rightly proud of a suspension system that meets all the demands made on it without impinging on boot space, and the 80-litre fuel tank is retained.
The differential (which can be locked) is flexibly mounted on the suspension cross-member and on an additional forward cross-member, and the suspension geometry involves what Audi call a four-joint traPezoidal arm system. The lower trapezoidal arms, made of pressed steel, have widely spaced pivot points which accommodate braking moment as well as lateral and longitudinal forces, while the top link is adjustable and provides lateral location only. The forged hub carriers, the same as those used at the front, house double taper roller bearings. ABS braking is standard equipment,
tit°,111h it is cancelled either or both ttr. differential locks are engaged and can Pt !witched off by the driver if, for instance, he !’s geing along in fresh snow. There is an innovation here, in a brake pressure limiting y e which responds to lateral acceleration. s reduces the braking force at the rear wheels if the car is braked in a corner, when the inside wheel would be the first to bring the ABS system into operation prematurely’
and the braking distance is therefore reduced. Another development which could revolutionise turbocharger technology is to encase the turbine in a water jacket which is pan of the car’s cooling system, thus reducing the temperature of the oil system from 180 to 130 degrees Centigrade. Dr Ferdinand Pitch, director of research and development, claims that this will increase the average life of a turbocharger unit from 120,000 kilometres to 250,000 keen (155,000 miles). The life of a turbocharger unit is seriously impaired if the engine is switched off immediately after running at high speed, say at a motorway filling station. “Normally the engine should tick over for .about a minute, but this is not always the case” says Dr Pitch. In thc development stage with KKK, Audi had to add a little cooling fan be the water around the turbo unit was vaporising, but they have not patented the system and other manufacturers will be free to carry out their sewn developments. Pitch, who in his time at Porsche designed and developed the 917 model, is clearly still performance orientated. “This will be particularly valuable in rallies. If the car has a small accident it will prevent damage to the turbo before it can continue. . . we tell our drivers to keep the engine running if possible.” Due to the extra complexity of the Quattro Sport’s engine installation, however, it will be well into next season before the water-cmled turbo will be seen in
rallies. In the engine department a knock sensor has been added to the specification enabling Audi to raise the compression to 8.8:1, thus improving low-speed response. In the case of the new Audi 90 and the revised Coupe models the bore size has been increased slightly to 81 mm, and the capacity goes up to 2,226 cc. A number of other
modifications include raising the compression ratio of the normally aspirated engines to 10:1, fitting hydraulic tappets for the first time, modifying the torsional vibration damper on the crankshaft, and modifying the Bosch K-Jetronic injection system with an additional air feed to the injectors, electronic idle speed stabilisation and an overrun cutoff.
In real terms the engines are a little more powerful — up to 136 bhp for the top 5-cylinder models — quieter and more economical too. Both the Coupe and 90 models have the more aerodyamic front-end treatment recently introduced on the revised 80 model, reducing the Coupe’s drag figure to 0.36, and the 90 saloons have slightly higher boot lids than the 80s, increasing the luggage space.
The line-up for Britain is a little different for the Coupes, VAG (United Kingdom) Limited planning to import the 1.8-litre 4-cylinder, the 115 bhp 2-litre 5-cylinder as the (;T model and the 136 bhp version only in Quattro form, this one arrived in January.