At the 2009 Frankfurt Motor Show Lamborghini has presented the Reventón Roadster, the open-top version of the Reventón, first introduced at Frankfurt in 2007.

Powered by a 6.5 litre twelve-cylinder with 493 kW (670 PS), the Roadster sprints from 0 to 100 km/h (0 to 62 mph) in 3.4 seconds and reaches a top speed of 330 km/h (205 mph).

The open-top Reventón will be produced in less than 20 units that will be sold for 1.1 Million Euro (without taxes). Deliveries will begin October 2009.

Design

The Reventón Roadster is derived from the same creative thinking as the Coupé. Its designers found their inspiration in aviation – the aggressive wedge shape evokes images of fighter jets.

Styling cues include the powerful arrowhead form at the front, the mighty air intakes pulled way forward, the broad side skirts, the upwards opening scissor doors and the rear end with its menacing edges.

Details set stylish accents, such as headlamps featuring bi-xenon units with LEDs forming the daytime running lights and indicators. The rear lamps are also equipped with LEDs.

Like the Coupé, the Reventón Roadster measures 4700 mm (185 in.) long.

It has a wheelbase of 2665 mm (105 in.) and is 2058 mm (81 in.) wide and 1132 mm (45 in.) high. The driver and passenger seating positions are low and sporty, separated by a substantial central tunnel.

Behind the two seats are two hidden pop-up bars that deploy upwards in just a few hundredths of a second in the event of an imminent rollover.

A fixed, horizontal wing-shaped member behind the seats bears the third brake light. The design of the Roadster’s long back is also quite distinct from that of the Coupé.

The engine hood is virtually horizontal and a total of four windows made from glass provide a view of the mighty V12 in all its technical elegance.

Body Structure

The base bodyshell of the Reventón is already so stiff that the Roadster requires only minimal reinforcement. It has a dry weight of only 1690 kg (3,725 lbs.), just 25 kg, (55 lbs.) more than the Coupé.

Like the Coupé, the cell of the Roadster is made from high-strength steel profile and carbon components joined with specialist adhesive and rivets. The bodyshell is made almost entirely from carbon fibre elements, with sheet steel used only for the outer door skins.

Grey paintwork

A unique paint finish completes the razor sharp design language of the Lamborghini Reventón Roadster. For this special edition, designers have created a new shade of matt grey called Reventón Grey.

As for the Reventón Coupé, which is a slightly different shade of grey, this is a matt paint finish that, in the sunlight, displays an unexpected impression of depth thanks to its special metal particles.

The wheels of the Reventón Roadster also incorporate the interplay of matt and glossy elements. The five spokes of the rims each bear a Y-form, and on each spoke are mounted small crescent-shaped wings made from matte carbon. These provide not only an unusual visual impact, but also a turbine effect that further improves cooling of the mighty ceramic brake discs.

Interior

The cockpit is structured with technical clarity, the interfaces arranged for functionality. Like a modern aircraft, the open two-seater no longer has classic analogue instrumentation – instead, information is delivered via two transreflective and one transmissive liquid-crystal displays.

The driver can switch between two modes at the touch of a button – one digital view with illuminated bars and one level with classic round dials, albeit with changing colour graphics.

Centrally located at the top of the display is the G-force meter. It represents the intensity of the forces acting on the Reventón Roadster under acceleration, braking and heavy cornering; the same format used in Formula 1.

The instruments are mounted in a casing machined from solid aluminium which is housed in a carbon fibre dashboard. The interior displays uncompromisingly clean craftsmanship and features a host of carbon fibre applications – e.g. on the centre tunnel – aluminium, Alcantara and leather. The central panels and the seat cushions are perforated, with precision stitching gracing their outer edges.

Technical Features

The twelve-cylinder engine that powers the Reventón Roadster is a Lamborghini icon and one of the world’s most powerful naturally-aspirated engines.

With a compression ratio of 11 : 1 and a displacement of 6496 cc (396.41 in3,) it generates 670 PS (493 kW) at 8,000 rpm. Its maximum torque of 660 Nm (487 lb-ft) kicks in at 6,000 rpm.

Two chains drive the four camshafts that, in turn, operate the 48 valves. Together with the three-phase adjustable intake manifold, the variable valve timing delivers a meaty torque build-up. Dry sump lubrication ensures that the hi-tech power unit has a constant supply of oil, even under heavy lateral acceleration. The absence of the oil sump means a low mounting position – benefitting the car’s outstanding handling characteristics.

In classic Lamborghini style, the aluminium engine is mounted longitudinally in front of the rear axle, with the transmission ahead of it beneath the centre tunnel. This layout results in 58 percent of the overall weight being borne by the rear wheels.

This layout accommodates the Viscous Traction permanent all-wheel drive. Under normal conditions, it sends the vast majority of the driving force to the rear wheels. Should they begin to spin, the central viscous coupling sends up to 35 percent of the power via an additional shaft to the front axle. Limited-slip differentials are located there and at the rear axle with 25 and 45 percent lock respectively.

The e.gear automated six-speed sequential manual transmission is activated hydraulically via two steering wheel paddles. In addition to the “Normal” mode, the system offers a “Corsa” and a “low adherence” mode.

Each wheel boasts double wishbone suspension, with one spring strut on each side of the front axle and two each at the rear. The front end of the car can be raised by 40 mm (about 1.6 in.) to protect the underside of the vehicle over potholes or on steep entrances into underground garages.

The open two-seater runs on 18-inch wheels. The front tires measure 245/35, while the rears are 335/30. Dedicated air channels in the bodyshell cool the four wheel brakes. Carbon-fibre ceramic discs are standard – they have an extremely lightweight construction, operate with virtually no fade, are corrosion-free and achieve the highest service life. Each disc has a diameter of 380 mm (~15 in.) and is gripped by six-piston callipers.

A further distinctive characteristic of the Reventón Roadster is its calm directional stability even at extremely high speeds. Alongside the bodyshell design and the smooth underbody, which culminates in a powerfully formed diffuser, the rear spoiler deploys from the rear edge at about 130 km/h (80 mph) and adopts an even steeper angle as of about 220 km/h (136 mph).

Development

The design, CAD work and model making that took place in the Centro Stile, which opened in 2004, were accompanied continuously by specialists and test engineers from the Research & Development Department.

The Design Department is directly linked to the neighbouring Ufficio Tecnico, ensuring rapid implementation of ideas. Lamborghini’s capabilities also include the independent development of the complete electronic platform. This incorporates all control units – including those for the V12 and the innovative cockpit displays.

All units of the Reventón Roadster are being built on the Sant’Agata Bolognese production line.

(Source: Lamborghini)