Sit behind the wheel of the 2010 Jaguar XKR and you come face-to-face, literally, with “the Growler.” The steering wheel emblem is the face of a big cat – a jaguar, of course – its teeth bared and looking ready to pounce. The real growl is just a push of the pulsating “Start” button away.

The 2009 Jaguar XKR, with its 420-hp supercharged engine and cat-like agility, might have seemed like the last car that needed an upgrade. However, Jaguar is merely living up to its heritage by making a great car even better. The 2010 XKR not only gets revised styling, but a new 510-hp engine and new advanced chassis technology for even sharper handling.

All XK series models sport revised styling for 2010, highlighted by a distinctive new front-end design, new LED rear lights and a new lower rear body valance. You could say the front looks more like it is growling, which certainly would be appropriate.

The all-new engine in the 2010 Jaguar XKR is a knockout. It’s the supercharged Gen III AJ-V8, a 5.0-liter unit that replaces the previous 4.2-liter engine. The new V8 employs direct fuel injection and a unique new type of variable valve timing technology.

Just for comparison’s sake, the 2010 XKR engine has the same horsepower and, at 461 lb/ft, 10 percent greater torque than another high-performance British grand tourer, the Aston Martin DBS. That car, however, costs nearly three times the 2010 XKR coupe’s MSRP of $96,000. (The 2010 Jaguar XKR convertible’s MSRP is $102,000.)

The XKR’s powerplant indeed growls and not just figuratively. Jaguar engineers devised a special air intake feedback system that, when combined with the sound of the active exhaust system, yields the most exhilarating soundtrack yet from a Jaguar. Be assured, though, that it purrs with refinement around town. The six-speed transmission, now with the unique JaguarDrive gear selector that debuted in the XF sedan series, translates that growl and power to a zero-to-60 mph leap in just 4.6 seconds.

On a practical note, service intervals are now 15,000 miles versus 10,000 for the previous engine, helping to reduce operating costs.

The XKR is more than a compelling story of power. The Jaguar brand name itself was chosen some 70 years ago because the cars possessed agility that competitors did not. A key source of that agility in the 2010 XKR is its racing-inspired aluminum structure, which helps make this cat several hundred pounds lighter than other high-end European sports and GT cars.

Attached to that structure for the first time in an XKR are Active Differential Control and Adaptive Dynamics – technologies also shared with the 2010 XFR sedan. The electronically controlled differential and new suspension system work together to optimize traction under hard acceleration and cornering.

In the Jaguar tradition, sophisticated and elegant luxury abounds in the 2010 XKR. Full leather interior is standard with three color choices – Warm Charcoal, Caramel or Ivory. A new Dark Oak veneer is the standard finish for the XKR’s wood-trimmed areas with Dark Mesh Aluminum also available. Ten-way front power seats are standard with heating, memory and a unique R seat style.

The luxurious Jaguar Suedecloth headlining is standard, also in the convertible, which lowers its top at the touch of a button in less than 18 seconds. When lowered, the convertible’s flush-folding roof retracts completely into the bodywork behind the rear seats under a smooth cover that retains the car’s elegant, sporty lines. The convertible’s rollover protection system remains hidden unless it is needed, deploying instantaneously as necessary.

When you’re not listening to the music of the XKR’s supercharged V8, the standard Bowers & Wilkins 525-watt audio system with Dolby^® ProLogic^® II surround sound fills in nicely. The system includes eight speakers, high output, low distortion Kevlar^® mid-range speakers, aluminum dome tweeters and a unique amplifier. The Portable Audio Interface allows simple, direct connection of iPod and MP3 players with full control via the touchscreen or steering wheel-mounted controls.

The 2010 Jaguar XKR is ready to growl, ready to prowl and just waiting for you to unleash it.