Jaguar's flagship XJ sedan is one of the world's most stylish and sophisticated luxury cars. With its sleek profile, aggressive stance and trademark feline gaze, the last thing this big cat needs is more swagger. But more swagger is exactly what the XJ has when there's an "R" added to its name.

At Jaguar, "R" is more than just a letter. It's Jaguar's performance brand, which for the last 25 years has been pumping out factory-tuned versions of its XJ, XK and XF models, among others, with the simple guiding principle of "high performance luxury."

In the case of the new 2014 XJR, "high-performance luxury" is typical British understatement. The XJR puts a supercar-like 550 horsepower under the bonnet and to the wheels. The XJR adds a bit of edge to the XJ's interior and exterior styling, too, with smoked wheels, a rear spoiler, and supportive sport seats among other niceties.

At $116,000 to start, XJR also adds a lot of added cost to the equation. Is it worth it? Well, we got a chance to wring it out on the pavements and, yes, on track to see just how sharp this kitty's claws can get.
The Basics

The Basics

Sticker price: $116,000 (+$895 destination charge)

Invoice price: N/A

Engine: 5.0-liter Supercharged V-8

Transmission: 8-speed automatic with paddle shifters

Performance: 550 horsepower, 502 pound-feet of torque, 0-60 mph in 4.4 seconds

Fuel economy: 15 mpg city, 23 mpg highway, 18 mpg combined

Seating: 4 or 5 people

Cargo: 15.2 cubic feet in trunk
Exterior Design

Exterior Design

With its long, slinky profile, standard panorama roof and blackout rear-window treatment, the XJ is already one of the sportiest looking luxury sedans on the market, so Jaguar didn't have to do much to make the XJR look fast. Still, subtle modifications include a discreet chin spoiler, chrome outboard fascia trim, a black-mesh grille, side-sill extensions, quad exhaust-pipes and a subtle aero flap on the trunk to enhance high-speed stability.

Charcoal-painted "Farallon" 20-inch wheels and bright-red brake calipers are probably the most conspicuous ways to tell the XJR apart from workaday XJs from 20 paces. Step a little closer and you may see the green and red "R" badge on the trunk, as well as discreet "XJR" letters tucked within the shiny chrome fender vents.

Unchanged are the XJ's scowling headlamps, clawmark taillamps and a delicate looking band of chrome around the windows. And like other XJs, the XJR comes in short and long wheelbases.

Could Jaguar have made the XJR look more extroverted? Certainly. But we won't complain, since in the flagship luxury sedan world, it's rather unbecoming to flaunt your power, even when there's 550 horses under the vented bonnet.
Interior

Interior

As with the exterior, changes to the XJ's swank interior are subtle. Most creature comforts that are optional on lesser XJ models are made standard, including a soft, nappy Altantara headliner that contrasts with the shiny piano black and/or carbon fiber trim found throughout the cabin. Almost everything else you can touch is covered in "Jet" black leather, with available red, ivory, or saddle-colored contrasting seating surfaces.

The XJ's kicky interior design remain in tact. We love the low, sloping, leather-covered, stitched dashboard that proves that big luxury can be done without installing a credenza in the front of the driver. Perched atop the dash are large round air registers with nifty rings that light up with the dash controls at night.

We are ready for Jaguar to move on from the Motorola flip-phone-inspired ice blue lighting and the chintzy-feeling transmission dial, but otherwise we love being inside this car.

Passenger And Cargo Space

Passenger And Cargo Space

With its low roof, the XJR may not be the best match for drivers over 6-foot-3, but thanks to the full-length, two-panel panorama sunroof it does not feel claustrophobic. The front seats are sportier and more firmly bolstered than those on other XJ models, though they are delightfully comfortable for long, straight-line cruising.

Particularly impressive is the rear seating area of the long-wheelbase model, which adds nearly five inches more stretch-out-and-cross-your-legs room and fold-out tray tables in the front seatbacks. The rear seats themselves are wonderfully sculpted, like perfectly bolstered shells, and recline a few degrees for added comfort. And the view from back there is particularly striking, with all of the glass windows on each side and above, underscored by what appears to be a continuous swathe of piano black wood or carbon fiber trim sweeping along the doors into the dashboard, not unlike the bow of a yacht.

Trunk space is about average for the class at a spacious 15.2 cubic feet. The same can be said for in-cabin storage in the armrests, glovebox and door panels.
Driving Dynamics

Driving Dynamics

Clearly, high-performance is something the R-brand folks take seriously. Otherwise, they may not have felt compelled to give the car Jaguar's most serious V-8 -- a 550-horsepower, twin-supercharged 5.0-liter monster motor with 502 lb-ft of torque going to the rear wheels via a state-of-the-art eight-speed transmission with shift-paddles. The XJ's lightweight aluminum body has always bestowed it with a quick and nimble feel, but the bigger performance package is enough to make a driver take the long way home every day.

How quick? Jaguar says it will hit mile-a-minute speeds in 4.4 seconds. Based on our experience in other cars that fast, we think Jag may be being modest. Top speed is said to be 174 mph (we did not try to hit it). We did, however, savor the V-8's sound. Oh yes, the sound. You may never turn on the XJR's mellifluous Meridian stereo systems once you hear it.

Thanks to various steering and suspension modifications, the XJR can claw the road with the tenacity of a cat scampering up a tree. The tires can occasionally slap bumps a bit hard out on the road, at least by luxury car standards, but considering just how well the big car could turn and hold the road it's a tradeoff that seems perfectly in sync with the car's stated purpose. Some track time with a professional driver showed us just how high this car's handling and braking limits are, an experience that left us with ear-to-ear grins and utter respect for the talents of the R engineering team.

And for what it's worth, the XJR's fuel economy of 15 mpg city and 23 mpg on the highway isn't all that awful for a car so powerful.
Tech And Infotainment

Tech And Infotainment

If there is a fly in the ointment, it's the screen-based center stack controls. When the current-generation XJ was conceived, Jaguar resisted fitting the interior with a fussy control puck like BMW's iDrive or Mercedes-Benz' COMAND systems, instead choosing to integrate most stereo and navigation system controls as well as some climate functions (like seat heat/ventilation) into a single screen. Sadly, that screen is too small and does not easily allow for safe multi-tasking. The system can feel a bit slow to react to inputs, too. Most new systems in competitors (and indeed, most Fords, for that matter) use larger screens and/or quicker and more logical interfaces. Mercedes-Benz and BMW seem to have worked the fussiness out of their newer systems, so this is a fail for Jaguar's team that seems not to have prioritized the system.

Like other XJ models, the R has simulated gauges on a flat instrument screen. On one hand, they do cool things like turn red when "Dynamic" driving mode is selected, and fade out all speedometer numbers except those within about 20 mph on either side of the car's actual speed for ease of reference. On the other hand, the fake dials look, well, fake. Also, for this kind of coin, we wouldn't mind seeing a few more technological flourishes, such as a head-up instrument display and/or active bolstered seats.

As for the sound systems, we wouldn't change a thing, thank you. With 380 watts and 12 speakers, the Meridian-designed base audio system features full surround sound. The upgrade system is also designed by Meridian, and pumps out 825 watts through 18 speakers, tailoring surround sound fields for each individual occupant. Nice.
Bottom Line

Bottom Line

At $116,000 to start, it's hard to consider the XJR a bargain, but compared to similarly horsepower-endowed super-lux competitors, such as the BMW 760Li, Audi A8 W12, and Mercedes-Benz S63 AMG, it sort of is a good deal. Furthermore, subjectively speaking, the XJR also feels a bit more, dare we say, casual than those more uptight übersedans. And the only thing that comes close to this XJR's athleticism is the Maserati Quattroporte, which is much less powerful, yet way more expensive.

All told, the XJR is one of those special automobiles that hits all the right emotional buttons that a six-figure automobile should, but that not all six-figure automobiles do.

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