The ultimate statement of Audi performance has always been its RS family, with the RS4 wagon traditionally attracting the most attention for its high performance practicality. These limited edition Audis offer cargo space with supercar performance and handling.
Based on the current B8 Audi A4 platorm, this is the third generation RS4 and European deliveries are scheduled for late summer 2012. Unlike the previous B6-based RS4, which was available in sedan and wagon formats, the new car returns to RS family tradition and will only be built on the Avant platform.
While BMW has stated it will be switching from its high-revving V8 engine to a more economical and tractable six-cylinder turbo engine in the next M3, Audi RS is again using the same naturally aspirated V8 engine that powers the RS5 Coupe and was seen in the previous B6 RS4 as well as the R8.
The hand-built 4,163cc unit, with its distinctive red cylinder covers, produces 450hp at 8250rpm and maximum torque of 320 lb-ft from 4000 to 6000rpm. This will power the RS4 Avant from 0-62mph in 4.7sec on to a governed top speed of 155mph – this can be increased to 174mph if required…
Official estimates claim potentially fuel consumption of up to 21.4mpg on the combined cycle test.
It appears that the option of a manual transmission has been dropped in favor of the standard seven-speed S tronic transmission. The dual-clutch gearbox allows drivers to shift automatically or change gears manually using the lever or paddles on the steering wheel. There is also a Launch Control available to impress the neighbors!
Like every Audi RS model, the RS4 Avant features quattro permanent all-wheel drive, which has an advanced crown-gear center differential. The compact unit varies power distribution between the front and rear axles, with the option of up to 70% going to the front, or as much as 85% to the rear. The default 40:60 ratio of the rear-biased configuration favors agile handling.
The sport differential from the S4 quattro and RS5, which actively distributes power between the rear wheels, is available as an option.
The self-locking crown-gear center diff works with a torque vectoring system, which acts on all four wheels. If the load on the inside wheel is reduced in a corner, the torque vectoring system brakes it slightly before it skids. The electronic stability program (ESP) also offers a Sport mode and can be fully deactivated.
The chassis has a five-link set-up at the front and a self-tracking trapezoidal-link rear assembly, much of which is crafted from aluminum to reduce unsprung weight.
The new speed-dependent power steering is anelectromechanical system with a direct steering ratio for precise road feel. It helps the driver stay on course by making slight corrections when braking on surfaces with different levels of grip.
Polished 19”, ten-spoke forged wheels with 265/35 R19 tires fill the fenders, and the RS suspension is 20mm lower than a standard A4 Avant. For a more extreme stance, two different 20” wheels with 265/30 tires can be specified as an option.
Mounted behind the wheels are internally vented wave disc brakes with gloss black calipers.
The eight-piston front calipers operate 365mm rotors – which are both drilled and have a wave-like outer contour. They are connected to aluminum hubs with pins to isolate heat build up. The wave shape of the rotors shaves roughly 6 lb off the unsprung weight.
For the front axle, Audi offers the option of 380mm carbon fiber ceramic rotors and six-piston calipers in anthracite grey.
The Audi drive select driving dynamics system is standard. The driver can switch between comfort, auto and dynamic mode to determine the characteristics of the steering, S tronic transmission and throttle response.
Audi drive select can even vary the exhaust system note, double-declutching when downshifting in dynamic mode. If the car is equipped with an Audi navigation system, a driver-programmable ‘individual’ mode is also available.
In addition to the sport differential, another component available for Audi drive select is dynamic steering. It varies its steering ratio by nearly 100% depending on speed, and will automatically countersteer at the cornering limit for even more precise and stable handling.
Dynamic Ride Control (DRC) will be available as another option. The system connects diagonally opposed pairs of shock absorbers by way of oil lines and a central valve, and promotes stability and composure at speed. The three damping modes it offers will also be controllable via the Audi drive select system.