2007 Audi Cross Cabriolet Quattro

Dynamic chassis

The dynamic chassis on the Audi Cross Cabriolet quattro combines precision and dynamism with a high level of stability. The suspension mountings, steering, wheels and brakes have been developed for top performance and numerous aluminium components are used to keep unsprung masses to a minimum. As in the Audi A5 and A4 models, the five-link front suspension makes a considerable contribution to the car’s dynamic character.

By moving the differential to the front and the clutch to the rear, the front axle is repositioned 154 millimetres further forward. Together with the relocation of the car’s battery to the boot, this optimises the load distribution between the front and rear axles.

The front axle comprises five suspension links per wheel – one supporting link and one guide link form the lower level and two guide links the upper level. The fifth link – the track rod – joins the steering box to the wheel bearing housing. All suspension links are forged aluminium parts, which guarantee low unsprung masses and extremely precise wheel location.
If sporty handling is to be combined with a high standard of ride comfort, the unsprung masses must be kept as low as possible. Audi has pursued this approach for all the rear-axle components. The upper transverse links and the track rods are
aluminium forgings. Their high rigidity ensures that toe and camber angles change very little when dynamic forces act on the wheels.

The springs act directly on the wheel carriers. The design engineers adopted this layout because it enabled them to increase the ride comfort to luxury-car level and at the same time achieve the road dynamics of a sports saloon.

Stepless – the shock absorbers

The CDC (continuous damping control) shock absorbers, similar to those that Audi already uses on the luxury Q7 SUV with air suspension, are twin-tube gasfilled hydraulic units with an additional external valve and connecting pipe. Their operation can be continuously varied.

An electromagnetically energised proportional-action valve regulates the flow of hydraulic fluid between the inner and outer damper tubes. A smaller flow crosssection makes the damping characteristic firmer, a larger one makes it softer.

The control unit applies adaptive operating characteristics within the mode the driver has chosen via Audi drive select. It adapts to match the driver’s driving style and the road conditions. Even from the comfort mode, the shock absorbers can be switched in an instant to a firm setting if desired, though not to the absolute limit. They are fitted in conjunction with sports suspension springs, which still provide a good standard of ride comfort, even off road.

The control unit selects the optimum damping force for the current driving situation, for instance firmer damping to prevent body roll and pitch when cornering fast or braking, lower damping force in off-road terrain where the surface under the wheels is hard and uneven.

Electric ride height adjustment

As a true SUV, the Audi Cross Cabriolet quattro displays impressive off-road talents. These include its innovative electric ride height adjustment, which varies ground clearance by a total of 40 millimetres at the touch of a button. It works by means of electric motors under each wheel’s spring plate that raise or lower the vehicle body. In addition to its low weight, one of this system’s winning features is its operating speed: the preselected ride height level is reached in a maximum of four seconds.

This brings obvious advantages for the driver, not only when venturing into rough off-road terrain. The height of the vehicle body can be adjusted to make getting in and out that bit easier and also – as already seen in the Q7 – the rear can be lowered separately for easier loading into the luggage compartment. For reasons of safety, handing dynamics and economy, the body moves automatically to the low setting at speeds above 80 km/h, thus both lowering the centre of gravity and reducing air resistance. The system is operated either via the MMI, a button in the luggage compartment or even from outside the vehicle using the key.

Controlled power – the ceramic brakes

The Audi Cross Cabriolet quattro is equipped with ceramic brakes on all four wheels for effective deceleration even under the most demanding conditions. Compared with conventional steel discs, ceramic brakes not only last four times longer, up to 300,000 kilometres, but also offer high resistance to fading. The significant reduction in weight also leads to advantages in terms of comfort and handling, thanks to reduced unsprung masses.

On the front axle, 380-millimetre ceramic discs are fitted in combination with 21-inch wheels. The rear discs have a diameter of 356 millimetres. The elaborate cooling duct geometry of the ventilated brake discs ensures optimum brake disc cooling. Firm grip on the brake disc is guaranteed at the front by 6-piston monobloc aluminium brake callipers, and at the rear by floating-calliper brakes.

Audi drive select

The Audi Cross Cabriolet quattro is equipped with Audi drive select, as optionally available in the current generation of the bestselling Audi A4. This allows you to preselect three highly individual configurations for the engine and gear-change characteristics, and the adaptive shock absorbers. The result is a car that can be enjoyed in completely different ways and that offers a huge potential in the field of efficiency.

The default setting is the "dynamic" mode, which is automatically activated every time the engine is started and is designed purely to produce the dynamic yet comfortable driving feel typical of the brand, which Audi drivers have come to expect of their cars.

The "sport" mode gives the Cross Cabriolet quattro an emphatically sporty driving feel. The shock absorbers are set firm, the engine responds more spontaneously to the throttle and the tiptronic transmission’s shift points move higher up the engine
speed range: the ideal basis for active driving pleasure on winding roads. When the driver switches to the "efficiency" mode using the MMI, the engine and S tronic respond gently to commands from the accelerator and shift paddles. This setting is ideal for a relaxed driving style, as well as offering tremendous potential for effectively lowering fuel consumption, and therefore emissions too.

In efficiency mode, the air conditioning system is automatically switched off and is only reactivated if the driver so wishes. A completely new interpretation of the cruise control system also moves the vehicle with minimum fuel consumption, allowing it to drop below the set speed within a certain lower limit in favour of lower fuel consumption, for example on gentle uphill stretches of motorway. The efficiency mode also makes use of route data from the navigation system and the adaptive cruise control to reduce speed early and make driving as economical as possible by avoiding the need for heavy braking when approaching a tight bend or a vehicle driving ahead.

In this way, under normal operating conditions and combined with a forwardlooking driving style, Audi drive select can achieve fuel savings of well over 20 percent compared to dynamic mode.

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