Drive Away 2Day

2013 Jaguar C-X75 : Concept Cars

On announcing the cancellation of the C-X75 supercar last December, Jaguar brand director Adrian Hallmark tried to put a positive spin on the story, saying that the car’s development would be completed and that regular Jaguars of the future would benefit from the work done on its hybrid technology, aerodynamics, and carbon-fiber composites. He also promised that Car and Driver, which had followed the project closely, would have a chance to experience Jaguar’s vision for a 21st-century supercar. That opportunity came a few days ago and showed that Jaguar, together with Williams F1, is capable of producing a high-tech road car that could compete with the likes of the La Ferrari, McLaren P1, and Porsche 918.

Gestation Recap
The C-X75 began as a show car “as close to a pure art form as a car can get,” according to design chief Ian Callum. That was because it was unfettered by the need to package a big V-8 or V-12; the idea was that it would pack a hybrid system that combined electric motors at the wheels and two micro gas turbines as generators. Unexpectedly, in May 2011, Jaguar announced it had joined forces with Williams Advanced Engineering to turn the concept car into an environmentally focused, limited-edition production model to challenge the Bugatti Veyron and its ilk.

As the plan evolved, the gas turbines were discarded in favor of a conventional piston engine working with two electric motors, one at each axle. But if the original, much-admired shape and proportions were to be retained, the engine would have to be very compact. Jaguar and Williams devised what might be the most advanced four-cylinder road-car engine in history: 1.6 liters of displacement, with a mechanical supercharger and an exhaust-driven turbocharger, direct and port fuel injection, gear-driven camshafts, variable valve timing, and dry-sump lubrication.

The gasoline engine develops about 500 horsepower on its own, and each of the electric motors contributes as much as 195 horses. A race-car-style carbon-fiber monocoque chassis envelops a 19-kWh lithium-ion battery pack and a gas tank, forming the center tunnel. The performance targets: 0 to 100 mph in fewer than six seconds, a top end of more than 200 mph, and a CO2 figure in the official EU test cycle below the 89 g/km rating of the Toyota Prius.

Actually, the five C-X75 prototypes have never run on a public road. Our drive was at Jaguar Land Rover’s Gaydon proving ground, but the prototypes have also been tested on race circuits in England and at the Nardo speed bowl in Italy.

Running Gaydon in Prototype No. 3
So no one really knows for sure if this 890-hp gasoline-electric hybrid is suitable for everyday use, but indications are that it is. Er, would have been. A lap of the twisty Gaydon handling track in prototype No. 3 in pure electric mode at speeds of up to 100 mph demonstrated seamless power delivery and a nimble character that would be easy to live with. That’s assuming you could tolerate the jet-plane-like whooshing sounds, rising and falling in response to accelerator input.

Switching to the parallel dynamic mode at Gaydon’s high-speed circuit, a completely different animal was released. Ferocious acceleration was accompanied by the wail of a highly tuned race engine, running up to 10,000 rpm between fingertip shifts of the seven-speed automated manual transmission. If you were fast enough out of the final corner, the C-X75 could reach 200 mph by the end of the main straight (a former RAF runway), and it still felt as if it could accelerate some more, making glorious noises from its internal-combustion engine. The C-X75 felt solid and reassuringly stable even near maximum speed. The deployable wing is said to generate 441 pounds of downforce at 200 mph.

Chassis Details
The Jaguar/Williams team is satisfied with the performance and dynamics of the C-X75, but because there are no current production plans, finishing touches such as regenerative braking aren’t enabled. Recharging the batteries of these prototypes requires plugging into an electrical outlet.

Williams employed a Formula 1 control platform (as used before F1 standardized such things) as the basis for the so-called Vehicle Supervisory Controller that coordinates the car’s many systems. Engineers have been experimenting with different front-to-rear torque splits and the interaction with the electronic rear differential, managing the percentage of drive torque sent to the front wheels to achieve a handling balance that still allows a touch of power oversteer.

The transverse-mounted seven-speed gearbox is supercompact. To save space and weight, it has no reverse gear; backward movement is provided by reversing the rotation of the electric motor packaged alongside it. The front-mounted electric motor, which drives through an open differential, has a fixed ratio equivalent to the seventh speed of the gearbox.

Over in This Corner, Hailing from Coventry
The show car’s wild interior, with seats molded into the contoured floor, has been redone in the interest of ergonomics, and the wide, conventional doors replaced by upward-swinging scissors pieces, like the McLaren 12C’s, to allow easier access when parked in a confined space. Although the two cars used for track testing have roll cages and monitoring equipment, the final prototype, No. 5, has been finished and prepared for exhibition to show the million-dollar supercar that might have been.

It’s not a coincidence that the C-X75 is being aired just as the first reviews of the Porsche 918 have appeared. (Read ours here!) The specs of the two cars are remarkably close: both have combined max power of just under 900 horsepower, and the quoted weights are identical at 3750 pounds, so their performance should be similar. But the Jaguar was planned to be more expensive and more exclusive than the Porsche, and when rumors circulated six months ago that advance sales of the 918 were well below expectations (the order books for the hybrid Ferrari La Ferrari and McLaren P1 had yet to open), JLR decided, literally as well as metaphorically, to pull the plug.

Aside from the commercial realities, program director Paul Newsome of Williams says the C-X75 has met all its targets, and he is confident the technology can be used in other applications. More than 100 patents have been applied for, most concerning the high-voltage side of the hybrid system.

JLR’s work with Williams continues. The partners already have a dedicated research department for hybrid powertrains that will launch a diesel-electric version of the Range Rover later this year and that expects to have ”performance hybrid” Jaguars in its future model range.

Jaguar also claims the C-X75 has advanced its expertise in aerodynamics and composite materials. The prototypes presented particular challenges regarding cooling and airflow management that can be put to good use elsewhere, and their body construction has shown how carbon fiber could be incorporated with the aluminum structure of future production models.

Soon, Jaguar Land Rover will be mass-producing four-cylinder engines of its own design. It’s too bad none of these will spin to 10,000 rpm.


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Sources : 2013 Jaguar C-X75 Concept Photo | 2013 Jaguar C-X75 Concept Article | 2013 Jaguar C-X75 Concept Engine Photo | 2013 Jaguar C-X75 Concept Photo 2 | 2013 Jaguar C-X75 Concept Interior Photo | 2013 Jaguar C-X75 Concept Rear Photo

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