Audi is introducing its new sporty top models in the midsize class – the S4 and the S4 Avant. Their engine, a three-liter V6 with direct fuel injection and mechanical turbocharging, delivers a powerful 245 kW (333 hp). It accelerates the S4 to 100 km/h (62.14 mph) in just 5.1 seconds, but on average only uses 9.7 liters of fuel per 100 km (24.25 US mpg).The quattro permanent all-wheel drive system transfers its power to the road in style, which is then converted by the sport suspension into dynamic handling. Upon request, Audi can equip the new S4 and S4 Avant with innovative technologies that further increase their lead over the competition. The seven-speed S tronic changes gears with lightning speed, and the new sport differential distributes the torque as needed between the rear wheels. The new Audi S4 will be unveiled to the public for the first time at the Paris Auto Show from October 2 to 19.
The heart of the new S4 and S4 Avant is a completely redesigned engine. The 3.0 TFSI, the newest member of the Audi V-engine family, is an outstanding example of how the brand with the four rings blends performance and efficiency. The V6 generates its power from a displacement of 2,995 cc, is equipped with a supercharger, and delivers 245 kW (333 hp). The sedan sprints to100 km/h (62.14 mph) in just 5.1 seconds, and the Avant in 5.2 seconds: they both have an electronically governed top speed of 250 km/h (155.34 mph).Click here to See More Features Photos
The “T” in the 3.0’s TFSI nomenclature no longer merely stands for “turbo”, but rather for the concept of supercharging in general – extensive testing on the big V6 has proven the superiority of mechanical charging. In conjunction with direct injection it is far superior to twin turbochargers, both in terms of packaging and of starting performance and responsiveness.
The compressor is so compact that it easily fits inside the 90-degree V of the cylinder banks, in place of the intake manifold. Two four-vane rotary pistons counter-rotate inside the turbocharger at up to 23,000 rpm. Two charge-air coolers are integrated into the housing and are connected to a separate coolant circuit. An impressive array of measures keeps the noise generated by the compressor to a minimum.
The engine-driven belt that powers the mechanical charger provides full thrust right from idling speed. The 3.0 TFSI delivers its maximum 440 Nm (324.53 lb-ft) at 2,500 rpm and maintains this constantly until 4,850 rpm. In fourth gear, the vehicle accelerates from 80 to 120 km/h (49.71 to 74.56 mph) in just 4.4 seconds. Thanks to the extremely short gas paths, the sonorous, supercharged V6 responds spontaneously to the throttle, even more so than a naturally aspirated engine of the same displacement.Click there to More Car Interirors Online
Furthermore, the new 3.0 TFSI achieves exemplary fuel efficiency. On average, the sedan uses 9.7 liters of fuel per 100 km (24.25 US mpg), and the Avant 9.9 liters per 100 km (23.76 US mpg) – an improvement of 3.4 liters (26 percent) compared with its predecessor. The Audi technology of gasoline direct injection was what made this great efficiency possible in the first place. Unlike conventional concepts, it allows the compressor to be located behind the throttle valve. In view of the low density of the intake air at loads below supercharging level and when coasting, its rotors are free-running and the amount of power required to drive them is low.
Dynamism and efficiency: The new seven-speed S tronic
The V6 power in the new S4 and S4 Avant flows into a six-speed transmission, fitted as standard, which shifts quickly and precisely. As an option, Audi offers a state-of-the-art dual-clutch transmission – the seven-speed S tronic is extremely dynamic and highly efficient. The driver has the option of driving in fully automatic mode or selecting the gears with paddles on the steering wheel or directly with the shift lever – all of which provide impressively quick gearshifts. The gearshift feel is dynamic, comfortable and very precise – typically Audi.New Audi S4 Avant Interirors
The seven-speed S tronic consists of two separate transmissions and uses two multidisk clutches that control the various gears. The large K1 clutch guides the power via a solid shaft to the pinions for gears 1, 3, 5 and 7. A hollow shaft rotates around the solid shaft; it is connected to the compact K2 clutch, which is integrated within its larger counterpart and controls the pinions for gears 2, 4, 6 and reverse gear.
Customized torque distribution: The sport differential with Audi drive select
The new, active sport differential ideally complements the quattro drive system and lends it even greater fascination. When the steering wheel is turned or Exclusive Digital Cars Showcase Onlinethe car accelerated in a corner, power is redirected in a controlled manner to the outer rear wheel, literally pushing the vehicle through the corner. The system intervenes to counter any signs of understeer or oversteer. For the driver, this means reduced effort at the steering wheel and even higher lateral acceleration.
The active sport differential is a new type of rear-axle differential. A superposition gear was added to both the left and right sides of the classic differential; it rotates ten percent faster than the wheel’s drive shaft.
Both components can be connected through a multidisk clutch, which runs in an oil bath, and is operated by an electro-hydraulic actuator. In most driving situations, the clutch can divert almost the complete input torque to one wheel in this way.
Controlled by an array of sensors and a high-speed computer, the active sport differential needs less than 100 milliseconds to redirect power. Drivers can adapt their manner of driving, along with characteristics for the load changes, to three performance maps. Unlike competitors’ systems, the Audi sport differential is just as effective when the engine is driving the wheels as it is on the overrun or when the car is coasting freely.
Audi drive select: The driving dynamics system
The Audi drive select driving dynamics system is a further high-end technology featured on the new S4 and S4 Avant. It accesses the throttle response characteristics, the shift points for the seven-speed S tronic and supports the speed-dependent servotronic steering. With the press of a button, the driver can decide whether these systems should operate in “comfort,” “auto” or “dynamic” mode. If the vehicle is equipped with the MMI operating system, a fourth mode is available which the driver can program according to his own personal tastes and preferences.
Audi drive select can only be ordered in combination with one or more of three additional technologies – the sport differential, adaptive control for the shock absorbers, or dynamic steering, which is an additional high-tech solution. Its zero-play superposition gear, which is driven by an electric motor, varies the ratio by almost 100 percent depending on the speed being driven. In terms of driver safety, the dynamic steering assists the ESP stabilization program by using steering intervention to keep the new S4 and S4 Avant on track when cornering at the handling limits. In many instances, the system renders ESP intervention superfluous.
New Audi S4 & Audi S4 Avant - Buy OnlineAn athletic look: The design
Both the Audi S4 and the S4 Avant look athletic and muscular on the road. Some of the most striking modifications to the exterior design are the special aprons, the aluminum-look exterior mirrors, the 18-inch S-design light-alloy wheels, the side rocker panels, the restrained spoiler at the rear and the quadruple exhaust system. The xenon plus headlights with daytime running lights and the rear lights are further distinctive touches.
With regard to multimedia, Audi offers an attractive technology package. The communications and entertainment technologies portfolio includes the competition-beating MMI operating system, various types of radio and sound systems all the way up to the high-end solution from Bang & Olufsen, two navigation systems, an iPod interface, and a highly convenient Bluetooth car phone.
Luxurious features such as the three-zone deluxe automatic air conditioning and the dynamic cornering light system known as adaptive light round out the optional equipment.
Audi will begin delivery of its new S models in March 2009.
