On the evening before the Paris Motor Show, the Volkswagen Group presented not only the production-bound Passat GTE plug-in hybrid, but also staged the world premiere of the XL Sport—a highly efficient sports car concept based on Volkswagen’s XL1 diesel plug-in hybrid.

The XL Sport is a sister model of the XL1; both share the same basic design—although not the same powertrain. The main element they have in common is the body, many parts of which are manufactured in carbon-reinforced polymer (CFRP), with a monocoque featuring slightly offset seats for the driver and passenger.

The XL Sport concept car is a sports car with 200 PS (197 hp, 147 kW) of power and a top speed of 270 km/h (168 mph) that was created based on the hyper-fuel-efficient XL1. Operating at the rear of the XL Sport—and the technical highlight of the powertrain—is a modified V2 engine from the new Ducati 1199 Superleggera—the world’s most powerful two-cylinder motorcycle engine. (Ducati is also part of the Volkswagen Group.) This engine, together with a 7-speed DSG, launches the sports car from zero to 100 km/h in 5.7 seconds and revs up to 11,000 rpm.

V2 engine. Like the XL1, of which only 250 units will be built, the Ducati Superleggera is also being manufactured in a limited edition (500 units), in a process that embraces hand fabrication and high-precision industrial manufacturing technologies alike. The Ducati 1199 Superleggera’s V2 engine was slightly modified for use in the XL Sport but is basically the same as the motorcycle engine.

Due to its tough, lightweight titanium connecting rods, the 1,199 cc DOHC engine can attain speeds up to 11,000 rpm. The Superquadro’s high speeds are made possible by its extreme bore/stroke ratio (112 mm/60.8 mm) and the exceptionally short crankshaft stroke associated with it. In addition, the two four-valve cylinders, which are arranged at an angle of 90° to each other, feature a desmodromic valve control system (positive valve closure by a cam and lever system) that is typical of the high-revving Ducati engines and requires precision engineering to ensure optimum valve clearance.

Other features of the two-cylinder engine are the magnesium alloy clutch, cylinder head and oil pan covers; the two disks of the throttle valves; and the two injectors per cylinder. The XL Sport features a newly developed intermediate gearbox to reduce engine speeds by a factor of 1.86. Torque from the V2 engine (134 N·m) is transmitted to the rear axle via a 7-speed dual clutch gearbox (DSG).

Racing chassis. The chassis, incorporated in a high-strength steel space frame, consists of a double wishbone front axle with the dampers connected below in a pull rod configuration, and a double wishbone rear axle with the dampers connected above in a push rod configuration. High-speed tires sized 205/40 R 18 (front) and 265/35 R 18 (rear) are set on forged magnesium wheels, which offer a total weight reduction of 23.9 kg (52.7 lbs) compared with aluminium wheels. The XL Sport is decelerated by an extremely stable brake system with ceramic discs.

Aerodynamics. The Ducati 1199 Superleggera has the best power-to-weight ratio of any production motorcycle in history. In the world of the motor car, the XL Sport achieves something similar. In this case it is the ratio between weight (890 kg /1,962 lbs), power (147 kW / 200 PS) and aerodynamics (cd x A = 0.44 m²) that currently makes this concept car the fastest 200 PS car in the world. No other sports car has ever reached a top speed of 270 km/h with 200 PS, Volkswagen said.

One stand-out feature in this is the vehicle’s aerodynamics. As noted above, the coefficient of the drag coefficient (0.258) and the vehicle’s frontal area (1.7 m2) is 0.44 m². This is one of the best values ever achieved and a triumph for Volkswagen’s aerodynamics engineers and designers, made more impressive due to the fact that as a thoroughbred sports car, the concept’s design brief demands wide tires, a high requirement for cooling air and optimal downforce.

There are a number of individual features that contribute to the XL Sport’s performance in addition to the aerodynamic styling of the body. These include special air curtains that direct the air in the frontal area into specific channels; wheel arch ventilation; a further optimized underbody; lift-reducing air ducts in the hood; an extendible rear spoiler (powered by the same unit as in the Lamborghini Aventador); and adaptive waste heat vents incorporated in the rear hatch (louvre that opens and closes automatically as required to conduct excess engine heat away).

CFRP body. Volkswagen prefers CFRP components manufactured using the RTM process (Resin Transfer Moulding). The density of this material or its specific gravity is just 20% that of a comparable steel exterior skin, yet it is just as rigid and strong.

Front section. The front of the XL Sport features air intakes on each side of the headlights for the air curtains which feed the air optimally around the car’s bow and front sides. In common with the X1, the front section of the XL Sport does not have a conventional radiator grille, yet it retains the current Volkswagen design DNA, with horizontal lines dominating this area: specifically, a black cross-stripe combines with the dual headlights to form a continuous band. The actual air supply for cooling the Ducati engine is via vents in the rear wings.

Wing doors that swing forwards. The wing doors of the XL1 and XL Sport are reminiscent of those of a high-end sports car. They are hinged at two points: low on the A-pillars and just above the windshield in the roof frame, so they do not just swivel upwards, but slightly forwards as well. The doors also extend far into the roof. When they are opened, they create an exceptionally large amount of entry and exit space. The door windows are made of polycarbonate. The upper part of the windows is firmly attached to the exterior door skin due to the specifications of lightweight design, while a segment of the lower area of the side windows can be opened. The windscreen of both models is manufactured from a special type of thin glass.

Silhouette. Whereas the XL1 is at its widest at the front and tapers towards the rear, the XL Sport is just as wide at the back as at the front. From above, the shape is that of a classic racing car, with the doors retracted like a waist. At each of the A and B pillars, there are distinctive air inlets and outlets to ensure an optimum air flow and for cooling the drive unit.

Small streamlined cameras integrated in the wing doors replace the door mirrors; the e-Mirrors (digital outside mirrors) send images of the surroundings behind the car to two displays inside the vehicle (e-Mirrors made their debut in the XL1).

Rear section. The XL Sport gives off a completely different impression compared with the XL1, especially at the rear, as this is now significantly wider. At the same time, the new XL Sport also has four specific features.

• The extremely wide, flat rear with its distinctive shoulders (powerful, wide surfaces above the wheels) and the extendible rear spoiler which occupies almost the full width of the vehicle’s rear end.
• As with the XL1 there is the coupé-shaped roofline without rear windshield. Merging into the roofline is the rear hatch that conceals the Ducati engine, the 7-speed DSG and 107 liters of luggage space. A louvre comprising five slats are seated flush in the rear hatch, which, depending on the temperature, open automatically to cool the drive unit.
• An iconic red LED ribbon that follows the shape of the rear section. At the sides the ribbon is framed by another, vertical, LED element which serves to emphasize the width of the XL Sport.
• A black diffuser that merges almost seamlessly into the completely enclosed underbody and is finished at each side with a chrome exhaust tailpipe.

Proportions. Despite sharing ground with the X1 in terms of its underlying design, the XL Sport has a look of its own. The reason for this is that whereas the XL1 was designed for uncompromising fuel efficiency, the design brief of the XL Sport took this a step further with the inclusion of uncompromising driving dynamics.

The special requirements regarding the downforce values of a 270 km/h car and the parameters of the drive technology led to the XL Sport being longer and wider than the XL1. Dimensions in detail: The XL Sport showcased in Paris is 4,291 mm long (XL1: 3,888 mm), 1,847 mm wide (XL1: 1,664 mm), 1,152 mm high (XL1: 1,153 mm). The wheelbase has also been increased to 2,424 mm (XL1: 2,224 mm).