There are four brand-new supercars at this year’s Geneva
motor show. All are advanced hybrids and made of carbon-fibre.
Although, with just 47bhp from its 803cc turbodiesel, a 100mph top speed and
0-62mph in 12.7 seconds, Volkswagen’s
XL1 appears puny compared with LaFerrari, the McLaren’s P1 and Porsche’s
918. This diminutive silver machine is, however, every inch a supercar, from
its hi-tech construction, to its 300mpg-plus fuel economy.
More than 120 years after the invention of the first motor car, isn’t it time
we changed our view of the supercar? Welcome to the new super, super
efficient. And when this remarkable two-seat coupé trundled silently into
this year’s Geneva show having traversed the Swiss Alps from Lucerne across
the precipitous 5,000ft Brünig and Jaun passes, it was averaging more than
140mpg. Having covered this entire project from its very beginnings, it was
your correspondent, along with development engineers, swapping turns at the
wheel.
In 1998, Ferdinand Piëch, the then head of VW, ordered his engineers to
develop a “ine-litre” car. This refers to the German measure of fuel
consumption of litres per 100km, which equates to 282.5mpg. Wolfsburg went
into overdrive, producing a carbon-fibre bodied, tandem-seat, single-piston
engined special. Looking as though he was about to tackle the Bonneville
salt flats, Piëch climbed behind the wheel for his last public appearance as
VW chairman in 2002 and drove from his office in Wolfsburg to the VW
shareholders meeting in Hamburg. In the rain and in chilly temperatures, the
canny old engineer beat his own target for the car, setting an average fuel
consumption of 317·4mpg at 43·5mph.
“We will never build a one-litre car,” he said at the time, “but it could give
us the knowledge to build a two-litre car.”
Having achieved its aims, the project languished, but eventually Piëch’s
replacement, Martin Winterkorn, and head of R&D, Ulrich Hackenberg,
resurrected it and debuted the next stage, the 189mpg, twin-cylinder hybrid
L1 at Frankfurt in 2009.
Hackenberg rejected the tandem seat as impractical, but Piëch suggested a staggered arrangement to limit the inevitable width increase. At 12-foot 9in long and just 3ft 9.4in tall, the XL1 is one of the slipperiest cars in the world, with a drag coefficient of 0.189. It is also the lightest hybrid, weighing a total of 1,752lbs – the resin-transfer moulded carbon-fibre body weighs just 507lb and the entire drive system 500lb.
The engine is half a Polo’s 1.6-litre turbodiesel, made in aluminium, with plasma-sprayed bores instead of iron wet liners, and a balance shaft to reduce vibrations. This parallel twin produces 47bhp and 88.5lb ft and is supported by a 27bhp/74lb ft electric motor with a plug-in hybrid system using a thin motor/starter and a 5.5kWh lithium-ion Sanyo battery. The transmission is a magnesium-alloy version of VW’s E400 seven-speed, twin-clutch unit driving the rear wheels.
The XL1 is simply a paragon of energy efficiency: LED lamps, narrow-gauge wiring with electrical fuses, carbon-ceramic brakes, electric air-con/heater, a fully faired underbody and polycarbonate side windows with anti-scratch coatings. The narrow wheels are magnesium alloy, the wishbone front and semi-trailing arm rear suspension is all cast aluminium and the hollow anti-roll bars are carbon-fibre. Crash safety is on a par with current VW models and in the event of a roll-over accident, the doors can be released by deploying the explosive hinge bolts. It all feels very special and just a tiny bit weird.
In normal operation, the XL1 stays in electric drive until full throttle is used or speeds exceed 62mph. Electric-only mode lasts 31 miles or until the battery charge falls to 14 per cent, whereupon the engine starts to maintain the charge and drive the vehicle, but not fully refill the battery. Recharging takes one hour from a UK domestic supply. EU Combined economy is 313.8mpg, using the EU’s rather contrived calculation for plug in. In fact, Hackenberg says that’s a rounded-up figure and the actual consumption is 0.83lit/100km (340.4mpg). Carbon-dioxide emissions are 21g/km and the 10-litre fuel tank and battery give a combined range of about 311 miles
Climb in and it is immediately apparent that big advances have been made since we first drove the prototype in Qatar in January 2011. Gas struts allow the scissor doors to swing up and down more freely and there’s less clackety resonance to the carbon-fibre body.
That said it feels pretty odd to drive around town. The throttle takes a firm prod and the car whines away, bobbing gently on its springs. Skinny Michelins crash through pot holes, the unassisted steering has a strange, over-centre feeling, although the regeration and friction brakes are combined well in one pedal. For all that, the moulded seats are very comfortable and the matt-black and piano-black interior, which was designed by a Brit, Andrew Hart-Barron, is delightfully simple and unadorned.
There’s a simple instrument binnacle from the VW Up in front of the driver, a selection of Polo/Up switches on the centre console and a Garmin unit giving sat-nav, engine and fuel economy information. Two six footers will fit comfortably, with 120 litres of luggage space under the boot behind the engine.
Out of town and at higher speeds the XL1 starts to calm down. Stark figures don’t adequately describe the urgency of the chirruping engine and whirring motor giving their all, which is more like a sci-fi car chase scene. Torque is limited to save the delicate transmission, but the XL1 goes quite as fast as you would ever want to on 115/80/15in tyres. The suspension tames the roads better at speed and road noise is muted. You never quite get used to that engine starting, though, which alternately sounds like a far-off woodpecker or an SDS drill in the ear canal.
“The only twin in the whole [VW] Group that sounds good is from Ducati,” laughs Heinz-Jakob Neuβer , head of the powertrain development. “This engine becomes smoother the more load you have, though, as we can put more pre-injection fuel into it - it’s all about combustion stability.”
The steering improves with practice and miles, although it loads up alarmingly with bodyroll through corners, which is a shame as the XL1 handles and rides quite well and you can’t help wondering whether VW has forgotten what a decent, unassisted steering system should feel like.
That said, up in the ethereal Alpine mist, the white XL1 slipped through the fog like a smuggler’s cutter, a ghostly apparition leaving not a trace of its passing, least of all CO². For that alone you’ve got to just love it.
Coyness doesn’t begin to describe VW’s approach to pricing. It wants to produce 50 cars initially, 200 cars after that, yet it can’t tell us what it costs and that marks this car down. As it stands, the XL1 is beautiful, peerlessly efficient, as technological as any rival supercar and great fun to drive.
It’s a bellwether for technology to come and a landmark car in its own right. Sorry to say this, but I loved it in spite of its faults.
THE FACTS
Volkswagen XL1
Tested: 803cc, parallel twin-cylinder turbodiesel and 5.5kWh, 60-cell, 230-volt Sanyo lithium-ion battery pack, with AC electric motor and seven-speed, dual-clutch DSG transmission driving the rear wheels
Price/on sale: TBC
Power/torque: Engine 47bhp/88.5lb ft, motor 27bhp/103lb ft. Total system output in “boosting” mode 68bhp/103lb ft
Top speed: 100mph (electronically restricted)
Acceleration: 0-62mph in 12.7sec
Fuel economy: 313.8mpg EU Combined (see text)
CO2 emissions: 21g/km
VED band: A (£0)
Verdict: VW’s XL1 moves the game on in super efficiency terms and also ushers in a new era where super doesn’t mean ludicrous power output and intergalactic acceleration.
