New Audi RS4
New generation of quattro drive
September 5, 2005 8:01 PM
Filed Under: Audi, German
Press Release
In Detail
The Audi RS 4 – the sports car for 365 days a year
The new Audi RS 4 from quattro GmbH breaks new ground in every respect, impressively demonstrating the leading-edge engineering embodied in the "Vorsprung durch Technik" slogan. The saloon features numerous innovations, delivering top performance whether on the road or on the track. This latest model developed by Audi subsidiary quattro GmbH combines motorsport technology with a high standard of practical value for everyday use. In creating this car, Audi's development engineers have succeeded in placing a sporty all-round concept on the road which is capable of thrilling its driver in every situation, whether in everyday motoring or on the race track.
The Audi RS 4 continues the tradition of quattro GmbH in bridging the gap between motorsport and everyday motoring. It is a car which combines emotion and functional perfection, meeting all the demands made by the driver of a high-performance car in general and an Audi in particular in today's motoring world.
At Audi, the “RS” abbreviation stands for unmatched performance, technological innovation and unique driving dynamics. To quote just two examples, the 420 bhp eight-cylinder engine is Audi’s first high-revving power unit, and also features its innovative FSI technology. A further forte of this exceptional V8 is its extremely compact size. The RS 4 for the first time features the latest generation of the permanent four-wheel drive system with asymmetric/dynamic torque distribution, under normal driving circumstances transferring 40 percent of the power to the front wheels and 60 percent to the rear. It is particularly well suited to a sport car of the calibre of the RS 4.
With each and every component of the new car being checked for minimum weight, the result of the consistent weight reduction process is a power-to-weight ratio of 3.93 kg per bhp.
The RS 4 is a truly unique, intelligent vehicle concept with superior drive train qualities, offering driving dynamics unmatched by any other car in its segment.
Engine
FSI delivers even better power and performance
The engine is key to the quality of any sports car. In the new RS 4, quattro GmbH has placed its trust in a compact V8 unit featuring petrol direct injection. In the 420 bhp high-revving eight-cylinder engine, FSI technology has reached a new highpoint. In this top product of what is a still young yet already highly successful technology, the petrol is injected directly into the combustion chamber, resulting in a uniform fuel/air mixture. Thanks to the cooling effect of the directly injected fuel, Audi’s development engineers have at the same time been able to increase the engine’s compression ratio.
The result is an even more efficient combustion process and, consequently, an even higher power output. This is demonstrated most clearly in the engine's more spontaneous responsiveness. Thanks to this technically highly sophisticated injection method, optimum power output is produced in every driving situation.
FSI technology is already deployed in the world’s most successful racing car, the Audi R8, winner of the legendary Le Mans 24 Hours race no less than four times in the last five years alone (to mention just some of the car’s outstanding achievements). The figures illustrate the outstanding potential of the eight-cylinder unit. At 7,800 rpm the 4.2 litre engine delivers 420 bhp of power output. Peak torque is 430 Newtonmetres at 5,500 rpm. And no less than 90 per cent of this maximum torque is maintained consistently throughout a wide range of engine speed from 2,250 all the way to 7,600 rpm. Performance on the road is naturally equally impressive: the RS 4 accelerates to 100 km/h in 4.8 seconds and reaches 200 km/h in 16.6 seconds. At 250 km/h the vehicle's speed is smoothly limited by an electronic control system.
The principle of the high-revving engine
Audi has deployed the high-revving engine principle for the first time in the RS 4. The maximum engine speed is 8,250 rpm. The significant advantages of this principle are superior power output at high engine speeds and a smooth, eager responsiveness all across the revs range. Further fortes are the car’s outstanding
agility and fast-revving response as well as the kind of racing-style engine sound drivers of such cars expect. As a result of these qualities, the eight-cylinder power unit provides maximum thrust and performance in virtually all driving situations.
The ultra-compact V8
The V8 power unit is ultra-compact in its dimensions, fitting snugly into the engine compartment of the RS 4 without requiring any modifications to the body. The camshaft and ancillaries, with the exception of the alternator, are all driven by a chain for easy maintenance. An all-new development, features of the eight-cylinder unit powering the RS 4 include modified pistons and conrods, a new crankshaft together with its bearings, and new cylinder heads. A twin exhaust system with enlarged pipes provides even higher power output. These extensive measures enabled the 4,163 cc engine to break through the magical 100 bhp per litre barrier.
The car's power-to-weight ratio is also impressive: 3.93 kg per bhp is a figure only the most thoroughbred sports cars were able to offer just a few years ago.
It goes without saying that the V8 featuring FSI technology complies with the Euro 4 emissions standard.
Drivetrain
New generation of quattro drive
Getting all this power on to the road was of course a significant challenge. Audi's answer is – of course – its quattro permanent four-wheel drive system. A quarter of a century's experience and market leadership in the four-wheel drive car segment represent genuine benefits for Audi's customers. The RS 4 features a new generation of quattro drive with asymmetric/dynamic torque distribution.
A Torsen centre differential distributes the power to the front and rear wheels as required, thereby ensuring optimum traction. In variable road conditions the power can be immediately diverted in full to the front or rear depending on the torque. The new distribution system, which under normal road conditions transmits 40 percent of the power to the front wheels and 60 percent to the rear, makes the Audi RS 4 an even more impressively dynamic drive. Alongside traction, controllability, stability, load reversal and transitioning, aspects of agility and steering have also been substantially enhanced, underscoring the highly sporty character of the car.
The term “Torsen” comes from “torque” and “sense” which, taken together, quite literally means “sensing the development and build-up of torque”. The Torsen differential is a self-locking worm gear. Thus the locking action is only prompted under the influence of the drive train. On braking and cornering the gearbox does permit differences in engine speed, however.
The rear axle differential is fitted with additional cooling fins. This is Audi's response to the high loads to which the RS 4 may be subjected.
Ensuring very short gearshift travel, the six-speed gearbox combines compact dimensions with low weight and a high standard of shift comfort. Adapted to the power unit of the RS 4, the gearing provides excellent power yield in practice, conveying the output of the engine to the driven wheels of the car with maximum efficiency.
Related Articles
Related Photo Albums
-
New Audi RS 4 (93 photos)
Add Comment
- Spied: MINI Cooper S Diesel & Clubman S Diesel
- Ford GT Geiger HP 790 Revealed
- Schumacher fit and could win F1 races - manager
- 2010 Dodge Viper SRT10 ACR sets Lap Record at Laguna Seca, World Debut in LA
- Audi RS6 Caught in Spain Going 133mph with 870kg of Hashish
- 2011 Suzuki Swift Latest Spy Photos in Germany
- MEC Design SLS AMG Design Proposals
- Britain's Bloodhound Project Seeks 1000 MPH World Land Speed Record in 2011 [Video]
Latest F1 News
Schumacher fit and could win F1 races - manager
Nov 25, 09 11:00 PM
FIA confirms victory in N.Technology legal case
Nov 25, 09 10:23 PM
Chandhok not disappointed by Force India snub
Nov 25, 09 10:13 PM
Briatore court ruling due January 5
Nov 25, 09 10:09 PM
Kobayashi to take Toyota sponsors to Renault?
Nov 25, 09 4:00 PM
Donington can still host 2010 British GP - Gillett
Nov 24, 09 11:08 PM
Merc also open to non-driving role for Schu - report
Nov 24, 09 8:30 PM
Brawn again plays down Schumacher rumours
Nov 24, 09 8:00 PM
Canada GP deal set for official green light
Nov 24, 09 7:30 PM
Campos reports progress with 2010 car
Nov 24, 09 7:00 PM














