Poised to pounce and newly transformed, the Jaguar XJ four-door sport sedan screamed out some power chords as we throttled it around Rock and Roll-ish West Hollywood, California. Jaguar chose the heart of the LA music scene to show the company has gone back to its sporting roots: Think of Austin Powers and the Mod '60s on steroids.

Penned by Jaguar Director of Design, Ian Callum and his team of designers in Coventry, England, the new XJ draws visual cues from a wide variety of sources. Glance at the big sedan from some angles and you'll see teardrops, sibling automobiles and its namesake animal, the Jaguar itself. Squint a bit while looking at the vehicle in profile, and you'll imagine a shape slightly reminiscent of "the leaper," the Jaguar leaping across the rear flank of the trunk, er, boot - the same cat that once resided as a hood ornament.

Jaguar Cars managing director Mike O'Driscoll, explained the company's recent return to the sporting style and culture: "We lost touch with our soul. We have returned with the XK, the XF and now the XJ to the proper sporting cars that we were known for."

Man walks into a saloon the other day"

For forty years, the XJ has served as the quintessential Jaguar. The large saloon, as it is known across the pond, has served a variety of uses ranging from executive transport to professional car (hearse and limousine custom builds) to family sedan for the ever-so-well-heeled. If the outgoing XJ had a North American counterpart, perhaps it would be the Lincoln Town Car. That's hardly what we call sporty, but neither was the outgoing XJ.

What a difference a year makes.

Incorporating much of the aluminum build that took place with last year's model, the 2011 is back for more of the same construction - but that's no bad thing since last year's XJ was state-of-the-art underneath its frumpy looks. This time add in some magnesium and composite alloys for reinforcement. Using nearly 2,800 aircraft-grade, self-piercing rivets and a Jaguar-developed bonding process, the XJ's monocoque has been put on a significant diet to become the lightest structure in its class. That stiffness and strength have been added to the overall package only adds to the bonus.

Beauty tends to be the result of a bunch of exquisite parts coming together to form one. The XJ has taken the new face of Jaguar and refined it to a new forward looking design complete with the large mesh-covered front fascia and grille, to its cat-like peepers to the invisible D-pillars and tear drop bright work as seen around the greenhouse area.

As seen in other cars of its ilk, the new XJ will be offered in an extended wheelbase model, known as the XJL. With five extra inches of legroom behind the front seats, and the addition of drop down desktops, it becomes one of the sportier looking executive transports on the market today.

The family jewels

The strength of the interior lies in what it brings to the table. We were in awe of the beautiful leather trim starting with the single-needle stitching along the top of the dashboard to the perforated leather seating with heating and ventilation, not to mention full massage function to insure that you arrive at your destination totally refreshed. There are 14 exterior paint and interior leather colors to choose from including nine wood veneer choices and extensive use of less-than-convincing plastic chrome. A panoramic glass roof is standard throughout the line and dramatically increases what is known as the daylight opening.

Actual analog gauges have been replaced by a Thin-Film-Transistor LCD panel that displays gauges where they would have been mounted. With the TFT screens, various gauges ranging from speedometer, tachometer, fuel, oil and water temperature gauges can be specially configured for each individual driver. Additionally, the far left area can also show turn-by-turn directions and a bird's eye view map during navigation usage. The gauges work in real-time although the tach displayed a touch of flutter when going through its paces. As we were driving prototypes, we expect they will be refined by the time actual sales units appear in dealerships - but we'll reserve final judgment for a more extensive drive.

Rounding out the interior, which is far quieter than most cars we test these days, the stellar 1,200-watt Bowers & Wilkins audio system with 20 individual speakers holds court. Think of it as sitting in front of Slash as he powers his Les Paul through a half-dozen Marshall Amplifier full-stacks. If you don't have an "Appetite for Destruction," you can always turn it off so you can hear the purr of the big V8 under hood, especially when you put your foot into it.

Speaking of V8s

Gee, I coulda had a V8. Actually, that's all you can have, albeit in three different flavors. All are direct-injection mills derived from the 5.0-liter AJ-V8 Gen III engine introduced in early 2009.

Jaguar's base offering is a naturally-aspirated engine producing 385 horsepower and 380 lb-ft. of torque. That's a 28 percent increase over the outgoing 4.2-liter engine from the previous XJ. With 19-inch wheels, it has a top speed of 121 mph.

Next up is the supercharged 5.0-liter engine with 470 ponies and 424 lb-ft. of torque. Finally is the special-order Supersport XJ Supercharged model, making 510 horsepower, and 461 lb-ft. of torque for pure kitty-scaring grunt.

Both supercharged models are on 20-inch tires and governed to 155 mph top speed. Curb weight of the short wheelbase naturally aspirated XJ is 4,045 lbs., while the supercharged models tip in at 4,281 lbs. Add 42 lbs. additional for a long wheelbase model. The base V8 is rated at 16 mpg in the city and 23 mpg on the highway, while the huffed versions are all rated at 15 mpg city and 21 mpg highway. Fuel misers, they are not, although the home market gets a diesel variant, too.

On the paddles

All of the variations of the XJ had paddle shift-equipped steering wheels to operate the six-speed automatic transmission like a manumatic. Designed to continuously adapt to each individual driving styles, they offered smooth almost imperceptible shifts, which would have gone unnoticed except for the swift kick in the pants that we got each time we decided to pass the lally-gaggers on Mulholland Highway near Malibu.

Once our foot squeezed the loud pedal, we were off, with the high-pitched squeal of the supercharger acting almost like one of those deer whistles you can find in the JC Whitney auto parts catalogs. Except this is one expensive - and powerful - deer whistle. A totally exhilarating ride, we just wished we didn't run out of road as quickly as we had. But when it finally did, the Supercharged XJL's brakes did quick work in bringing the fun to a halt. For those counting, front rotors measured in at 380 mm while the rears were almost as large at 376 mm.

Although the new XJ appears long and lanky like a Rock Star's girlfriend, its wheelbase is only an inch longer than the model it replaces. It does ride on a wider track though, which helps explain the poise and balance. We were especially impressed with the suspension kit with its unequal wishbones and forged components in front and its Adaptive Dynamics active damping system. Able to constantly change for the different road conditions we encountered, the XJ lived up to Jaguar's traditional mantra of providing a cossetting ride with a performance touch.

Although we were very much "in like" with the Sport Mode, which stiffens the suspension, remaps throttle, and adds a hint of aggression to the shift points, we found the Adaptive Dynamics did a better job with the varying conditions of the roads we encountered on Mulholland. The variable ratio power-assisted steering did a remarkable job of keeping the XJ pointed true especially with the changing road conditions and imperfections.

Leftlane's bottom line

Jaguar director O'Driscoll smilingly told us that at Jaguar, there is a feeling that "we are that small specialist company who will be known for their sporting cars once again."

We'd have to agree. With chief designer Ian Callum performing at the top of his game as the preeminent automotive stylist working today, the XJ doesn't necessarily chart a new course for Jaguar, but it sure does help define the brand. Smooth and capable, this isn't the Jaguar of yore. The XJ builds on the XF to give Jaguar a fully revamped product line that is bound to resonate with younger, hipper buyers ready for a little more rock and roll in their luxury sedan.

O'Driscoll tells us that the XJ is part of Jaguar's Phase I - if this is just the beginning, we can't wait to see what comes next.

2011 Jaguar XJ base price, $72,500.

2011 Jaguar XJL base price, $79,500.

2011 Jaguar XJ Supercharged base price, $87,500.

2011 Jaguar XJL Supercharged base price, $90,500.

2011 Jaguar XJ Supersport base price, $112,000.

Words and photos by Mark Elias.