Jaguar’s new XK Coupe is one of the best GT cars around, but critics have claimed it lacks the power to compete with cars such as the BMW M6 and Mercedes CLK63. That’s why German tuning company Arden has modified the engine to develop 392hp naturally aspirated or a massive 480hp in its supercharged guise. The standard XK, in comparison, comes with a 4.2L V8 producing 298hp/411Nm.

Arden has increased engine displacement to 4.5L to help achieve the higher power outputs. The supercharged XK accelerates to 100km/h in 4.8 seconds, 0.5 seconds faster than its Arden naturally aspirated counterpart, and as much 1.4 seconds faster than the production version. Also available in the package is a sports silencer system that keeps the XK quiet in neutral but increases its growl in full throw. A new sports suspension package lowers the car by 30mm, while 21” alloys shod in 255 front and 295 rear tyres help improve grip.

New aero parts include an Arden front spoiler featuring large air inlets, new side sills, cooling openings in the right and left-hand side of the bonnet, and a rear spoiler. Most tuner cars look overdone, but we really like the overlook of the Arden XK. On the inside you can choose between wood or carbon fibre trim inserts, and upgraded leather or Alcantara options.

Update: In semi-related news, Top Gear has crowned the XK its 'Car of the Year' and the 'GT of the Year'. Expect our test drive of the new XK early in the new year.

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