All-aluminium and lightweight construction, V8 power, curvaceous coupe and convertible bodies, a sequential shift six-speed transmission…and much more besides. When details of Jaguar’s ‘new’ XK – codenamed X150 – were revealed for the first time in August 2005, the specification sheet promised much. And it needed to, because it followed in a long line of Jaguar sports car from E-type through XJS and the steel-bodied XK8/XKR that it directly replaced, the latter being a solid success around the world, and re-establishing Jaguar as a credible builder of prestigious, desirable sports cars.

Following the closure of the historic Browns Lane factory, the new aluminium XK range represented the first step in brand’s much-vaunted product-led recovery plan and the first new Jaguar to be produced by a design team solely under the guidance of Ian Callum, the XK was generally very well-received by the world’s motoring press and public alike, and on the road it was a joy to drive from the word go. Both aesthetically and dynamically, the XK is a Jaguar that hits all the right buttons.

In terms of dynamics, the step forward from a steel-bodied XK to an aluminium-bodied car is significant, especially in convertible form. Lighter and stiffer, a new XK is significantly more nimble than its predecessor, and the ability gap between the coupe and convertible so small that it’s all but unnoticeable, even when driving hard. Buying a drop-top no longer means a compromised driving experience (but it does mean compromised boot-space, especially with the top down when a convertible has 100-litres less capacity than a coupe). On the road, you can expect a naturally-aspirated new XK to feel as quick as a previous generation XKR point-to-point, while the aluminium XKR raises the bar yet again.

Power for those XK and XKR models at launch came from upgraded versions of the 4.2-litre naturally-aspirated and supercharged V8s that also saw service in the previous generation cars. New fuel injection technology meant cleaner emissions, while in supercharged form the AJ-V8 sported variable valve timing for the first time (always a feature on the earlier 4.0- and subsequent 4.2-litre n/a engine) plus a twin air-intake system. Reliability wise, both have proven to be pretty much bomb-proof. The transmissions, too, have proven robust and are a joy to use. With a fully automatic ‘Drive’ mode, there’s also an automatic ‘Sport’ mode that, as well as holding the gears for longer, automatically blips the throttle on downshifts. On top of that, steering wheel-mounted paddles also enable manual sequential shifts, and changes are lightening fast.

Initially, Jaguar’s excellent CATS system (Computer Active Technology Suspension) was listed as an option for the XK, but within months it became standard fitment – in fact, we’ve never seen a car on passive dampers. All cars feature a keyless start system, but a desirable option is keyless entry. The fobs look no different, but keyless entry cars will have a small rubber button on the door handles. Walk up to the car, pull the handle and it will automatically unlock and, on leaving, press the rubber button and it will automatically lock if the fob is detected outside the car.

At launch all XKs and XKRs featured an exterior mast-type radio antenna, but this was often criticised for being unbecoming of a car of this class, and so from the 2008 Model Year both coupe and convertible XKs have their radio antennae hidden within the rear spoiler. Switchgear on these cars was also upgraded – and it wasn’t long before some more major changes were announced too.

Early in 2009, and for the 2010 Model Year, the XK range was given fresh appeal courtesy of the introduction of Jaguar’s all-new 5.0-litre AJ-V8 Gen III engine in both naturally-aspirated and supercharged form these having, respectively, peak power outputs of 385bhp and 510bhp. Direct injection was just one of the engines’ advanced new features – in short, they outperformed the old 4.2-litre units in every respect.

Also new was revised exterior styling with a squarer front end, new LED taillights, and numerous other detail changes. Inside too there were modifications, the most obvious being the adoption of the rotary gear selector first seen on the XF saloon – no more gearsticks on XKs… The suspension was upgraded with adaptive dampers (which constantly react to road surface, steering, throttle and brake inputs) replacing the old ‘two-stage’ CATS units, thereby improving the XK’s already impressive agility. And on the XKR, there was even a new electronically controlled limited-slip differential plus a ten per cent faster steering rack. Specification wise there was a new model too, a Portfolio version of the naturally-aspirated XK being offered alongside the standard model, the XKR retaining its own distinct specification.

Even this, though, wasn’t the end of the XK’s development story as in 2011, and for the 2012MY, the car has been upgraded once more. Slimmer LED headlights, a new front bumper treatment, revised rear end and horizontal rather than vertical power vents have brought with them a sharper look, and in performance terms there’s a sharper model too as, sitting at the top of the XK desirability tree, is the new £97,000 XKR-S. With its 5.0-litre supercharged V8 remapped to release 550bhp (an earlier, 4.2-litre limited edition XKR-S had no more power than the standard XKR), it’s capable of the 0-60mph sprint in just 4.2-seconds, while its top speed limit has been raised to 186mph. A lower ride height, revised spring and damper rates and new front suspension components are just some of the other engineering changes that mean the XKR-S is, for now, the ultimate XK.

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