The longitudinally mounted six-cylinder TDI in the Audi Cross Cabriolet quattro is the brand's latest diesel engine. With a power output of 240 bhp and 500 Nm of torque, at this stage in its evolution the 3.0 TDI is now more efficient than ever - its average fuel consumption is a mere 7.3 litres of diesel per 100 km. The engine is also equipped with what is currently the most elaborate emissions reduction system developed for a production engine: the ultra-low emission system.
This does more than just ensure that the vehicle complies with all current exhaust emissions standards worldwide. It already meets the expected limits of the EU 6 standard, which is only due to be introduced in 2014 - and does so with quattro permanent four-wheel drive and tiptronic transmission.
Design and body
Spectacular - a term which sums up the visual impact of the Audi Cross Cabriolet quattro painted in "Copper Sunset", whether the top is up or down. After all, without the hint of a compromise, the concept car combines classic Audi convertible hallmarks, such as the elegant fabric hood and aluminium A-pillar surface, with the undisguised dynamism of a sports car and the masculine presence of a genuine SUV.
4.62 m long, 1.91 m wide and with a wheelbase of 2.81 m: the Audi Cross Cabriolet quattro has the dimensions of a B-segment vehicle. The longitudinally mounted engine and the basic chassis and drivetrain architectures are taken from the inventory of modules used in the current Audi A4 and Audi A5 model lines. The SUV-style height of 1.63 m with the hood closed marks the most significant difference to these relatives of the Cross Cabriolet quattro.
High passive safety
Body stiffness and passive safety measure up to the typical standards of an Audi convertible. This is achieved with reinforcements to the A-pillar, the rear seat cross member and the sill area, in addition to a simple trick that exploits the extra body height of an SUV. The Cross Cabriolet quattro has a double underbody that turns the open profile of a convertible body into a closed structure, producing a major increase in stiffness. This design feature is efficient and economical in equal measure, since it replaces conventional modifications that involve numerous body components and require significantly more material, thus adding more weight.
The A-pillar and the top edge of the relatively shallow windscreen have been heavily reinforced to aid roll-over protection. Two roll-over bars, normally lowered out of view, are located behind the rear seats and are preloaded by powerful springs. If the vehicle is in danger of rolling over, the sensor system releases the spring retaining mechanism, causing the bars to shoot up within milliseconds to provide effective protection together with the A-pillars for the occupants in the interior.
The dominant element of the face-on view is the single-frame radiator grille with polished aluminium longitudinal struts, emphasising its vertical orientation - a clear signal of the concept car's sporty character. Behind its clear-glass headlight covers, the latest lighting technology can be seen: the Cross Cabriolet quattro is the latest Audi to be equipped with full LED headlights, which also feature the characteristic strip of daytime running lights and the electronically controlled swivelling cornering light. The turn signals, brake lights and tail lights also use fast-reacting LED light units. In addition to the front and rear light units, the exterior mirrors also have integrated turn signals.
In the side view, a distinct aspect of current Audi design can be seen in the shoulder line and dynamic line, which divide the vehicle body volume into a clearly defined sporty architecture. An equally characteristic feature is the proportion between the large body surface and shallow window area beneath the soft top's sweeping roof line - the hallmark of a sports car.
Within the pronounced styling of the wheel arches, the large 21-inch wheels with tyres of size 265/35 R21 send out a clear visual message and make an additional contribution to both driving pleasure and safety.
The fabric hood, which lowers itself fully automatically in a Z-fold behind the rear seats at the push of a button, is a trademark of all open-top Audi models. It is a stylistic feature that makes the car recognisable as a convertible, even with the hood up, and requires considerably less space in the rear and adds less weight than a complex folding steel roof.
In terms of noise and heat insulation, the Audi A4 Cabriolet's multi-layer fabric hood has long been found to compare very favourably with a solid roof in everyday use.
The underbody guard and metal running boards are classic off-roader features. They have been given a modern interpretation on the Audi Cross Cabriolet quattro. The running boards are integrated into the sills with a seamless transition to the door opening. The underbody guard covers the whole width of the vehicle. The LED front fog lights are integrated into the front section and the rear section accommodates the two exhaust tailpipes on the left and right.
Two generously sized doors provide access to the interior in typical convertible style. Thanks to the lack of a B-pillar and the easy entry front seats, rear passengers have no trouble getting in and out.
The rear loading solution is a perfect synthesis of convertible design and SUV functionality. When closed, the short stepped boot lid forms a continuation of the fabric hood's coupé line. When it opens, however, with the assistance of its gas springs, it lifts up high to provide a surprisingly large opening. At the same time, the glass rear window, which is hinged to the fabric hood, automatically lifts up too. The result is an opening to the luggage compartment that matches that of a conventional SUV equipped with an off-roader's traditional large tailgate. The loading width is 1.16 m and the load-area width is 1.05 m.
The Audi Cross Cabriolet quattro thus gives its driver the best of both worlds - the freedom and elegance of a convertible blended with the spaciousness and versatility of an SUV.
The interior of the Audi Cross Cabriolet quattro offers sophistication and ergonomically perfect solutions in all areas and with all its materials. The smooth and soft surfaces together with a gentle, natural blend of colours help to provide an atmosphere of absolute ease for the occupants. For additional convenience, each passenger has a heatable and coolable cup holder, located in the centre console at the front and in the side walls at the rear.
The driver and passengers enjoy the comfort of four spacious individual seats. The seating is entirely upholstered in "White Stone" leather. All occupants benefit from lateral support and excellent long-distance comfort. To enhance comfort when driving with the top down, all four seats are equipped with an airscarf function. Air vents on the head restraints serve to compensate for the air turbulence around the occupant's neck.
The space available in the second row is unique for the convertible world: the legroom, shoulder space and headroom are unbeatable, even with the roof closed.
The centre console continues far into the rear of the interior and provides the rear passengers with a stowage box with lifting lid.
A regular Audi characteristic of the cockpit area in the Cross Cabriolet quattro concept car is the way it is markedly angled towards the driver. The controls can be found here, while the front-passenger area is emphatically neat and architecturally clear-cut. In turn, the dashboard and doors are connected by flowing lines, while the cockpit itself is smoothly and organically integrated. In addition to the instrument dials under the dome-shaped cowl behind the steering wheel and a central LCD colour display integrated between them, the MMI also supplies information via its swivelling flat screen, well positioned within the driver's field of vision in the upper section of the centre console.
The MMI terminal on the centre console is also extremely neat. The central operating button and the six hard keys are the simplest way imaginable to operate the vehicle and infotainment functions.
In addition to the MMI terminal, the Cross Cabriolet quattro also has a touchsensitive sensor field (touch pad) in front of the MMI control element. Like on a laptop, this can be used, for example, to move image sections of the map display. The system is also capable of recognising and processing commands entered by tracing letters with your finger on the touch pad.
Google Earth, the interactive, three-dimensional atlas of the world, has gained a firm role on all personal computers. Now this software is making life easier on the road too. Audi has, for the first time ever, brought together the merits of the internet-based system Google Earth and its own built-in navigation system to create countless information facilities with user-friendly graphics.
The high-resolution display and photorealistic 3D maps provide a new dimension in intuitively understandable bird's eye visualisations that are rich in detail. The image angle and section can of course be adjusted to suit the driver's wishes at any time. By connecting to the internet, it will also be possible in future for traffic and weather information or even data on air quality to be included and taken into account in planning your route.
Using Google Earth's search function, the driver can also find addresses or service providers at the chosen destination and navigate directly to them - for instance restaurants, car parks or an Audi dealer.
To enter a navigation destination, there is no longer any need to enter the address by hand. The driver can click on an image in the Google Earth user interface and be directed to the identified destination.
Power is supplied by the latest stage of evolution of the three-litre diesel with common rail direct injection. It develops 176 kW (240 bhp) and has an impressive maximum torque of 500 Nm. It is this ultra-powerful TDI with a displacement of 2,967 cc that truly makes the Cross Cabriolet quattro a sports car. It accelerates from 0 to 100 km/h in just 7.2 seconds and has a top speed of 240 km/h - yet the average fuel consumption is a mere 7.3 l/100 km. The 500 Nm provide a mighty surge of acceleration starting from just above idling speed.
The 3.0 TDI is coupled to the quattro permanent four-wheel drive and an eightspeed automatic transmission. If the driver wishes to change gear manually, the shift paddles at the steering wheel can be used. The especially designed selector lever with integrated control wheel for gear selection is a newly developed variation of the shift-by-wire system.
The latest 3.0 TDI is notable not only for its low fuel consumption, but also for its especially clean exhaust. A diesel particulate filter is used to reduce soot emissions: it cuts the already low level of untreated emissions further, by more than 90 percent.
The cleanest diesel in the world
The new 3.0 TDI with ultra-low emission system is a further step forward that demonstrates the potential of the Audi TDI. Drivers are thrilled not only by the dynamism of 176 kW (240 bhp) and the outstanding torque of 500 Nm, but also by its modest fuel consumption and extremely low emissions.
The ultra-low emission system raises the principle of the direct-injection turbocharged diesel to a new level. To develop it, Audi's engineers combined a whole package of innovative measures. A new common rail system with piezo injectors operating at a pressure of 2,000 bar, high-efficiency exhaust gas recirculation and further optimised turbocharging join forces to achieve a significant reduction in untreated emissions.
A further technical breakthrough is the actual exhaust aftertreatment system, which cuts emissions of oxides of nitrogen (NOx) by as much as 90 percent. This system operates with the additive AdBlue, an aqueous solution of carbamide, small amounts of which are injected ahead of the DeNOx catalytic converter. In the hot exhaust gas, the solution breaks down into ammonia, which splits the oxides of nitrogen into nitrogen and water.
The AdBlue solution, which is biodegradable, is topped up as a routine operation each time the car is serviced, without the customer having to take any action. Since consumption of the solution is very low, Audi can guarantee that the amount carried on the car will be sufficient from one service to the next. The system will remain effective for the entire service life of the vehicle.
Thanks to their extremely low emissions, from 2008 Audi is able to sell its clean direct-injection diesels all over the world, even in the US states of California, Massachusetts, Maine, New York and Vermont where extremely stringent emission limits apply.
From 2010 on, Audi will be offering this new technology in further car and power output classes. The brand is pursuing a systematic strategy aimed at lowering fuel consumption and pollutant emissions still further. By 2012, Audi will have reduced its models' CO2 emissions by some 20 percent - yet their sporty character will be enhanced at the same time.
source : Audi Press