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Wolfsburg / Tokyo, 19 October 2005 – At the Tokyo Motor Show Volkswagen are presenting a prototype that could well make history as the most economical sports car of its time. The two basic figures: 3.4 litres per 100 km (69.2 MPG) average consumption, and 230 kph top speed (143 mph). The name of the sports car: EcoRacer. Eco, because fuel consumption and emission are extremely low; Racer, because the dynamic potential of this mid-engined sports car is thoroughbred and fascinating.
The EcoRacer – Fascinating combination of values
Thanks to its carbon-fibre (CFP) bodywork, the EcoRacer weighs only 850 kilograms (1874 lbs) and accelerates to 100 kph (62 mph) in a mere 6.3 seconds, driven through the DSG double-clutch transmission. This sports car, powered by a newly developed 100-kW (134hp) turbo-diesel engine of the next generation, thus presents a forward-looking synthesis of austere economy and impressive performance. 230 kph, 6.3 seconds, 3.4 litres – vital statistics that are as unusual as they are fascinating! When driven with economy in mind, the car can even travel more than 1000 kilometres (621 miles) on one tank filling (30 litres or 8 gallons).
The relationship between performance and consumption hint at a design that submits fully to the laws of aerodynamics. Nothing could be farther from the truth! The Volkswagen prototype on show in Tokyo displays avant-garde qualities. Its body styling, with a new form of sports-car front end, LED systems, tight proportions and powerful lines, demonstrates impressively that even very economical cars can rivet attention where they appear.
And this prototype is anything but a show-room mock-up. It can be driven without restrictions, and serves as a technology test-bed. And the EcoRacer is also a versatile all-rounder: As soon as a door is opened, the roof wing above it swings up, giving optimal access. The entire T-bar roof is removable. The rear hatch can be removed. And, last but not least, the frame of the windscreen can be exchanged for a module with a short, upright pane. This makes the EcoRacer, firstly, a coupé, secondly, a roadster and, thirdly, a speedster.
The EcoRacer – Minimum consumption, maximum fun
The EcoRacer is the vision of the ideal sports car, which needs very little fuel and yet offers great agility. A sports car that accelerates from 0 to 100 kph in a flash. A sports car with dynamics suitable for the North Loop of the Nürburgring. A sports car with extremely agile handling. A sports car that adapts to the most individualistic uses. A sports car that takes significantly less than 4.0 litres of fuel for 100 kilometres. A wild dream – and thus a case for Volkswagen Group Research, whose teams of experts draw together all the future technologies that, bit by bit, can be used to lower energy consumption and increase the joy of driving.
The future has already begun. The direct benefits to the motorist from the best brains in research and development pooling their know-how, are currently demonstrated by Volkswagen, with the new twin charger in the Golf GT. From just 1.4 litres cubic capacity, the engine develops 125 kW / 170 PS, thanks to the compressor (additional thrust at low revs) plus turbo loader (additional thrust at higher revs) and direct petrol injection. The doubly supercharged engine gives the Golf GT a speed of 220 kph; but it has an average consumption of only 7.2 litres of fuel for 100 kilometres. With the EcoRacer, the engineers at Volkswagen Group Research have added a new dimension to the philosophy of “minimum consumption for maximum fun”.
The EcoRacer – Body concept
As the mainstay of the EcoRacer, the team developed a carbon-fibre (CFP = carbon-fibre reinforced plastic) bodywork that was both light and stiff. Structurally, it is a CFP polycoque (the safety structure embraces room for two persons) with a fixed roll bar, CFP crash elements and a CFP skin. The main parts of the polycoque are a chassis pan, two side members and the dashboard.
The crash elements in the front area are the CFP crash absorber and an aluminium bumper cross-member. A further CFP module carries the engine and rear axle. The engine being mounted in front of the rear axle, there are boots at front and rear. The smooth vehicle floor with integrated diffuser, the boot lids, doors and roof elements are also made of CFP.
The door locks of the EcoRacer are electromechanical, being part of the Keyless-Entry-and-Go system. This not only releases the door catch but also swings the associated roof section upwards on a gas-pressure damper, so as to optimise the entry and exit. These roof sections and the so-called T-bar, the longitudinal web between them, can be removed completely and stowed behind the seats. And more: in a matter of minutes, the entire roof structure including the windows can be removed or converted. This, too, can be done in stages. The rear hatch, the coupe rear end, is removed. Without the hatch and the roof, the coupé now emerges as a roadster.
In the final stage, the roadster can be converted to a speedster. For this, a special catch in the area of the A column is simply released, to allow the windscreen with frame and the upper dashboard housing to be taken off. In place of this module, a minimalistic windscreen with its own cockpit cover is inserted. The result is a speedster in its purest form. Even in this version, you can drive the EcoRacer without a helmet. Firstly, the roll bar has been designed so that your head is protected even without a windscreen frame, should the car roll over. And secondly, the aerodynamics guide the slipstream over the heads of the driver and passenger.
The EcoRacer – LED by day and night
Technically, the LED headlamps and LED rear lights deserve particular attention. The headlamp modules are built with a depth of only 55 millimetres, thus allowing the front end to be completely newly arranged. Hitherto, especially in cars with a very short body overhang, conventional headlamps have been installed significantly higher than the axles. Because of the flatness of the LED headlamps, a much lower position is now feasible, even in a sports car like the EcoRacer.
To go into details: in the prototype, Volkswagen use two chromeplated headlamp tubes in each lamp. The upper tube is for dipped and full headlights. In addition to the LEDs for these main functions, the headlamp has an outer ring consisting of another 50 LEDs. This ring, when dimmed, plays the role of the side light and – at full brilliance – the daytime driving light that is already regulation in many countries. At the same time, the dipped headlights, reduced to 10 percent, are switched on. The signalling effect is excellent.
The lower tube in each lamp contains the LED fog lamp and the LED cornering light. Again, nothing is as you have come to expect. Take the cornering light, for example: it is generated by an LED that is angled three degrees outwards. There being no swivelling headlamp, the depth required for installation is reduced here, too.
The construction of the LED rear lamps is no less innovative. Here, Volkswagen use extremely bright RGB-LEDs; these can be activated in different colours, and are located as units on the three LED circuit boards of each rear light. Each of these circuit boards can be used separately or additively for the different lighting functions (tail light, braking light, f lasher). The area between the LED boards is coated with a very thin electro-luminescent foil, stylistically rounding off the so-called night graphics of the rear lamps to perfection.
The EcoRacer – Running gear
Dynamics and innovative concepts characterise the prototype’s running gear, too. On the one hand, it is very light, but on the other hand it offers quite obvious potential for extreme agility. The front double-wishbone axle is a completely new design. The wishbones are made of aluminium, as are the pivot bearings. The wheel bearings are courtesy of the Golf. A special tubular stabiliser, racing shock absorbers and racing springs round off the hot configuration for driving fun.
The four-control-shaft rear axle is based on the derivate that was used in the Golf. Its use in a central-engined sports car emphasises the potential of an axle that harmonises perfectly with front-wheel, rear-wheel and all-wheel drive. In the EcoRacer (weight distribution: 39 to 61) it was tuned specifically to the central-engine concept, and robbed of a few kilograms. For example, the wishbones are now made of aluminium. The tie rods are infinitely adjustable. And because a handbrake lever would only get in the way in a pure-bred sports car anyway, the development engineers went all the way and integrated the electric parking brake from the Passat. Racing springs and shock absorbers optimise the Nürburgring North Loop capability on the rear axle, too. The drive shafts are from the Golf GTI.
The central-engine configuration, the CFP bodywork and the very light running gear made it possible to achieve a weight distribution of 40 to 60 (front / rear), which is ideal for a sports car of this type. Weight and power make contact with the road through 175/55 R 17 tyres at the front and 225/45 R 17 tyres at the rear.
Part of the fascination of a sports car is not only the physically tangible acceleration, but also the no less intense braking. Up front, this job is handled impressively by internally ventilated brake discs 288 millimetres (11.3 inches) in diameter. On the rear axle, 286 mm (11.26 inch) discs do their bit to decelerate the EcoRacer ahead of all curves and obstacles as the situation demands. The main brake cylinder with its 10-inch brake booster is a contribution from Golf and Co. The ESP originated in the new Passat, its software being adapted to rear-wheel drive (Passat: front-wheel and all-wheel drive). Speaking of synergies: the pedal arrangement of the EcoRacer, with standing accelerator and hanging brake pedal, has already convinced the drivers of the current Golf GTI.
The EcoRacer – Engine / 1.5 TDI
Just as unique from the point of view of design as the whole body is the TDI engine of the EcoRacer. It is the future of the diesel engine. Clean, strong and very adaptable. The 1.5 TDI is still under trial. Like the new twin charger (TSI) among the directinjection petrol engines, the turbo-diesel direct injection engine is characterised by greatest agility at lowest consumption. Volkswagen refer to it as a highly charged downsizing concept.
The four-cylinder engine develops 100 kW /136 PS at 4000 rpm. Between 1900 and 3750 rpm, the 1484 cc four-valve unit develops a torque of more than 250 Newton metres. The compression ratio is 17.2:1. The unit is both light and compact, and – not only in the EcoRacer – it conforms to values planned for the EU-5 exhaust standard. The gearbox of the turbo-diesel is the DSG double-clutch transmission.
A deciding factor: the 1.5 TDI, presented in the EcoRacer for the first time, has the potential to implement the CCS process. CCS (Combined Combustion System) is the combustion process of the intermediate future, and combines the advantages of diesel and petrol engines, using synthetic fuels.
The EcoRacer – Interior/Cockpit/Operating concept
With all its economy, the EcoRacer is uncompromising when it comes to fascinating driving. And this is also reflected in the interior of the two-seater. Everything is tailored to the driver. He has a leather-upholstered bucket seat, and finds everything exactly where it should be. The multifunction display, with central instruments and integrated infotainment functions, is completely visible whatever the adjustment position of the steering wheel, and whatever the size of the driver. The secret is that the multifunction display is integrated in the steering column, and moves with the steering wheel. The steering wheel itself is a new design with an airbag, and measures 340 millimetres in diameter.
The cockpit offers an enormous range of functions. At the same time, the number operating elements concentrate on the essentials. There is not one superfluous switch. Thanks to the new central display, only those functions are visualised that are currently relevant.
The central dial allows the driver to query many different display functions. The predominant basic setting is either the speedometer or a rev counter; although they are digital, these functions have an analogue appearance. If the DSG is shifted manually, the display can, if desired, indicate when a gear-change is recommended through a red outer ring.
In addition, the TFT display can be switched from “Normal Mode” mode to a “Racing Mode” with a switch in the gear lever. In race mode, the characteristics of the electromechanical power-assisted steering (EPS) is varied towards more direct steering. The electronics make this possible. The steering is taken from the Golf. Overall, the steering of the EcoRacer has been designed in a very sports-car-like manner, taking into account the very light loading of the front axle. The running-gear engineers also adapted the track rods to the geometry of the front axle. In “Racing Mode”, the engine-gearbox characteristics are altered in parallel for an even more sporting set-up.
A further highlight is “Fingerprint”, an authorisation system with which the EcoRacer can be tailored to different drivers. If, for instance, your 18-year-old son or daughter with little driving experience wants to drive the EcoRacer, it is possible to activate a mode in which the sports car does not develop its full power, the top speed is electronically reduced, and ESP is always active.
The various display modes (colour or monochrome can be selected) are controlled by an MMI (Multi Media Interface) system. The MMI with its cursor and four function fields (Car, Navigation, Telephone and Audio) is located on the aluminium-effect central tunnel in front of the DSG gearshift, which is also newly designed. At this point, there is an integrated storage compartment with an interface for an Apple iPod (title display and menu control via the central display).
The EcoRacer’s 1.5 TDI is started and stopped by pressing a button on the switchboard (part of the Keyless-Entry-and-Go system). Also in aluminium are the knobs that control the air-conditioning, the inside door handles, the switches for the electric window lifters and the ventilator nozzles. The upper dashboard area is painted in body colour. The rear-view mirror is also mounted on this painted surface, which is part of the windscreen module, and can be swapped out in one piece.
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