Audi opens up new horizons. The A4 is a sporty car with superb presence on the road; it takes Audi forward into a new dimension on the midsize car market. The engines that power the saloon, both TDI and spark-ignition, in all cases with direct fuel injection, combine effortless power with high efficiency. The dynamic running gear and the use of many technologies taken direct from the large-car category are evidence of the brand’s lead in technical know-how. The new Audi is a new way to drive. It will reach the market at the end of November 2007, at a basic list price of about 26,000 Euros in Germany.
New high-tech options make the A4 driving experience even more fascinating: Audi drive select varies the engine, automatic transmission, steering and suspension damping characteristics to suit the driver’s preferences at any given moment. Audi dynamic steering varies its ratio according to the car’s speed and keeps the new A4 stable close to the handling limits by slight, almost instantaneous changes to the steering angle. The damping control system for the hydraulic shock absorbers varies the damping characteristic individually, to combine sporty driving enjoyment with maximum road safety.
The new Audi A4 is being introduced with a choice of five engines, their power outputs ranging from 105 kW (143 bhp) to 195 kW (265 bhp). The four-cylinder petrol engine, like the diesels, is turbocharged, and both types of engine have direct fuel injection. All the engines, with their supremely refined flow of power, make the A4 a pleasure to drive and, thanks to their high efficiency, consume distinctly less fuel than the previous versions.
Various transmissions are available: a six-speed manual gearbox, the tiptronic automatic transmission, the multitronic continuously variable transmission, and either front-wheel drive or quattro permanent all-wheel drive, which has been subjected to intensive development work that has made its performance even more dynamic.
The new Audi A4 has many fascinating sides to its character, all of them expressed by the outlines of its body. Their high-tech precision clearly demonstrates the leading position that Audi occupies in automobile design.
The new A4 has a spacious saloon body and a firm, muscular stance on the road. Its length (4703 millimetres) and width (1826 millimetres) exceed those of its core competitors, and sporty dynamics were the guiding principle in its development.
The proportions have a new balance compared with the previous model: the front body overhang has been considerably reduced and the bonnet and wheelbase are now noticeably longer. A long, coupe-style roof line emphasises the flowing silhouette. The roof meets the side sections of the body at an almost invisible zero-gap joint – just one of the many details that uphold the Audi principle of high technical precision.
The completely new outer body panels of the A4 consist of sculptured, curving surfaces framed by sharply defined outlines. The ‘dynamic line’ above the door sills rises slightly to the rear, the ‘tornado line’ below the windows slopes down. In this way the two contours add profile and dynamic balance to the sides of the car. Large wheels and boldly styled wheel arches emphasise this impression of concentrated energy.
The new A4 is a car that presents a confident personality to the outside world – an impression borne out by the broad, low, sporty ‘single-frame’ radiator grille.
The optional-extra xenon headlights are technical works of art, with powerful visual accents set by their electrodeposited chrome ‘wings’ and the standard daytime driving lights. Depending on the lighting technology used, their design differs: in the xenon plus headlights, the daytime driving lights each consist of 14 white light-emitting diodes.
The rear end of the body, which tapers strongly inwards, interprets the car’s sportiness in a most convincing way. The slim, tapered-off light units create a visual relationship with the road. The exhaust tailpipes are straight – even on diesel-engined cars a hint at the powerful character of the TDI engines. A4 models with the sporty S line exterior package differ in certain details, for instance the front air dam. The new Audi A4 can be supplied in 15 body colours – a wider choice than that offered by any of its competitors.
The new A4 is being launched with a choice of five powerful, refined engines. All of them, both petrol and diesel, use direct fuel injection, and the two four-cylinder units and the V6 TDI engines are turbocharged. With their splendid flow of power, these engines make driving the new A4 nothing less than pure pleasure. They also use less fuel than the equivalent engines in the previous model. Customers furthermore have a wide choice of high-tech transmissions: either a manual gearbox or automatic transmission can be specified. They transmit power to the front wheels or to a quattro permanent all-wheel driveline that has particularly dynamic settings.
The new 3.2 FSI, a member of Audi’s ultra-modern family of V engines, is the most powerful unit available in the new A4. From a displacement of 3197 cc, it develops 195 kW (265 bhp) and also delivers 330 Nm of torque all the way from 3000 to 5000 rpm. It accelerates the A4 3.2 FSI quattro with manual gearbox from a standstill to 100 km/h in only 6.2 seconds, and maintains this flow of power until the governed top speed of 250 km/h is reached. As an alternative from 2008 onwards, this engine can be combined with the 6-speed tiptronic automatic transmission; in either case, it delivers its power to the road via quattro permanent all-wheel drive.
The purpose of AVS is to ensure that the combustion chambers are always ideally filled; the throttle butterfly can then remain fully open in most cases, so that the engine breathes more efficiently.
The Audi A4 3.2 FSI with manual gearbox is content to consume an average of only 9.2 litres per 100 kilometres, 1.2 litres fewer than the previous car with a 188 kW (255 bhp) engine. About half of this improvement is due to the new valve actuating principle; the other half has been achieved by minimising internal friction. Oil pump volume is now smaller, with an optimised loss rating. Like the water pump, it now delivers a demand-controlled flow – another means of reducing fuel consumption.
The smaller of the two petrol engines, the compact four-cylinder 1.8 TFSI, is a highly efficient unit that develops 118 kW (160 bhp) and a torque of 250 Nm between 1500 and 4500 rpm from a displacement of 1798 cc. It accelerates the manual-gearbox A4 in 8.6 seconds to the typical main-road speed of 100 km/h, and maintains its thrust up to a top speed of 225 km/h. Yet according to the EU test cycle its consumption is only 7.1 l/100 km –1.1 litres per 100 kilometres better than the previous model. As an alternative to the manual gearbox, multitronic continuously variable transmission can be ordered, in both cases with front-wheel drive.
The 1.8 TFSI is a close relative of the 2.0 TFSI engine chosen three times in succession by a jury of international journalists as “Engine of the Year”. On this smaller version for use in the latest model line, direct petrol injection and turbocharging represent an ideal combination. Injection pressure has been increased to 150 bar, and new injectors distribute the fuel accurately to the combustion chambers. The turbocharger is exceptionally rapid in its response – at an engine speed of 2000 rpm it accelerates the engine 30 percent faster to a ten percent higher torque than the conventional 1.8T engine that powered the preceding model. For all its vigour, this four-cylinder unit runs quietly, in a most refined manner.
The three diesels for the new Audi A4 are two V6 units and a four-cylinder inline engine. Their strong performance makes them ideal representatives of a modern, powerful form of sporting character. Winning the Le Mans 24-hour race in 2006 and 2007 with the Audi R10 competition car was ample evidence of the power that can be summoned up by the TDI principle. Audi first introduced this efficient technology back in 1989, and it has remained the most efficient in the world to this very day. Since then, the brand with the four-ring emblem has not ceased to develop its technological lead.
The three-litre diesel is a new member of Audi’s V-engine family. It develops 176 kW (240 bhp) and has a peak torque of no less than 500 Nm all the way from 1500 to 3000 rpm. This large TDI unit, with its displacement of 2967 cc, makes the new A4 even more of a sports saloon. It needs only 6.1 seconds to accelerate to 100 km/h from a standing start, and has a top speed of 250 km/h, yet its average fuel consumption is a more than modest 6.9 l/100 km. The 3.0 TDI always has quattro permanent all-wheel drive.
The exhaust-driven turbocharger is also a unit from the latest design generation. A high-speed actuating motor alters the position of its guide vanes, so that high torque builds up more rapidly and spontaneously. The 3.0 TDI already complies with forthcoming Euro 5 limits. A novel exhaust gas recirculation concept with increased cooling performance is used to reduce emissions of oxides of nitrogen.
The four-cylinder TDI engine, with a displacement of 1968 cc, is a new interpretation of the strengths of the TDI concept. The piezo injectors of its common-rail fuel injection system operate at a maximum pressure of 1800 bar. Other innovative design features relate to the turbocharger, the toothed belt camshaft drive and the geometry of the pistons.
This two-litre engine develops 105 kW (143 bhp) and has the powerful peak torque of 320 Nm between 1750 and 2500 rpm – figures that explain why the new Audi A4 can accelerate from 0 to 100 km/h in 9.4 seconds and reach a top speed of 215 km/h. When combined with the six-speed manual gearbox, the 2.0 TDI is content with an average fuel consumption of 5.5 l/100 km, in which case the 65-litre fuel tank provides an action radius of more than 1,100 kilometres. The four-cylinder TDI can also be ordered with the multitronic continuously variable transmission. In both cases the front wheels are driven.
The 2.0 TDI also outperforms the Euro 5 exhaust emission limits. Thanks to improved thermodynamics, it can operate at a higher rate of exhaust gas recirculation, so that untreated emissions of oxides of nitrogen are lower. The cooler combustion process, with less oxygen present, would normally have an adverse effect on efficiency, but by careful attention to detail the development engineers have managed to transform this into an improvement in fuel consumption.
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