As Modern As The Hour

For over a decade, VW's been working on an automotive holy grail—the "1-liter" car. It's a vehicle that can travel 100 kilometers (62 miles) using just 1 liter of fuel (0.26 gallons). This comes out to an astonishing 235 mpg. . .

But development continued, because, as Piech said, "We could gain the knowledge to build a 2-liter car." Before the 1-liter prototype was retired to the company's museum in Wolfsburg, I had a chance to drive it. The experience was enthralling and offered a glimpse of a future where supercars are no longer huge, heavy V8 leviathans, but instead are delicate, gossamer creations capable of being coaxed for miles on a thimbleful of fuel. There was even an ethereal mode of operation called "sailing," where the motor stopped and the exceptional aerodynamics and high-pressure tires allowed the car to glide silently for miles.

The plug-in hybrid XL1, however, is as modern as the hour. The chassis is a 507-pound carbon-fiber monocoque with dramatic front-hinged scissor doors that's nearly 13 feet long, 4 feet tall and roughly 5 1/2 feet wide. It's a streamlined shape that appears to have been carefully sculpted by artists. But Walter de'Silva, head of VW's Design Group, says, "The car came out of the wind tunnel like that." Even so, the felt-tip fairies spent over two years nibbling away at the XL1's details to improve the aerodynamics; "it was incredibly intensive," says de'Silva.

In the last decade, the VW Group has been working on ways to make carbon-fiber bodies reliably and economically. This method, known as advanced resin transfer molding, allows the carbon fibers to be aligned in the direction of the forces, before they are shaped and mixed with resin and formed in the molds. With Austrian specialists Carbo Tech Composites, VW is using a similar construction method for the forthcoming Lamborghini Aventador supercar, but the carbon-fiber chassis is still some 80 to 100 times more expensive than one made from conventional stamped-steel panels. Dr. Harald Ludanek, VW's head of vehicle engineering, says, "To do this car in aluminium would have resulted in a 20 percent increase in weight, but it would have been 40 times less expensive."

One push of the starter gets the systems fired up, and after a five-second delay, another push prepares for takeoff, which is signified by a green "RDY" signal appearing on the dash. A well-sprung throttle pedal inhibits speedy getaways, so the driveline remains in electrical drive at first, but you immediately notice the direct and superbly weighted steering, which allows you to place the car accurately through the turns. Unassisted calipers squeezing ceramic brake rotors need a firm push from the brake pedal to activate, but are linear in operation. The argument still rages at Wolfsburg as to whether the brakes should have an electrical booster, which would add weight and complication but lighten the pedal pressures.

On electrical power, the 1795-pound VW feels zesty but hardly quick. Push the throttle harder and the parallel-twin diesel fires up with a thump from the driveline and a mechanical whir from the back. Refinement is only nascent, and that needs work before production. The ride is reasonably good on the special narrow Michelin tires, but over potholes or low expansion joints, you feel the unbending stiffness of the body shell. With all guns blazing and both propulsion units providing the urge, the XL1 is pleasingly brisk, and the fat slug of electrical torque wafts it forward between 40 and 60 mph. Road noise is quite audible, though, and when combined with the whirring motor and engine, the interior cacophony is borderline unacceptable. You can also hear the cooling fans mounted in the dorsal fin over the engine bay.

On my short drive around Doha, it was difficult to get a complete gauge of the handling, but the center of gravity is low, so it's reasonably stable. If there's one thing the XL1 has lost compared to its predecessor, it's that otherworldly easy-gliding nature. Blame the hybrid powertrain, which adds a considerable amount of heft.

First, the writing of this article is just lovely and should definitely be read in the original article at Popular Mechanics. Second, XL1 Could come into small series production in 2013!