In the new Jaguar XK, a secondary front bulkhead of aluminium and composite materials helps reduce noise transmission from the engine compartment and provides a dry area under the bonnet for accommodating electrical components. The new structure also has benefits in refinement; castings used for the mounting points for the engine, transmission and suspension make those points significantly stiffer, further reducing transmitted noise and helping to improve suspension dynamics. In terms of long-term strength, Jaguar's all-aluminium shell has durability approaching twice that of a traditional spot-welded steel body.

Another major advantage of this Lightweight Vehicle Technology is that all the necessary stiffness is in the structure of the body shell, with very large rectangular-section side sills. So the Convertible, even without a roof, does not need the traditional additional stiffening panels seen on many other convertibles - meaning no added weight and no penalty in stiffness or refinement. The aluminium monocoque construction is the biggest contributor to the low overall vehicle weight of the new XK, and the Coupe shell is over 30 percent stiffer than the previous model, while the Convertible boasts an impressive 50 percent improvement in torsional rigidity.

That lightweight body significantly also offers a 10 percent improvement in power to weight ratio. The all-new XK is up to 90 percent stiffer and 180kg lighter than key rivals, with a kerb weight of just 1595kg. In Convertible form the BIW weight, at just 287kg is 19 percent lighter than the previous Jaguar XK Convertible.

"The lightweight vehicle architecture really helps the all-new XK to handle, steer and brake better than ever," says Al Kammerer, Jaguar's product development director. "Imagine how much easier it is to turn a lightweight object travelling at speed compared to a heavy one. The aluminium chassis makes the Jaguar XK so much more controllable in corners and a whole lot of fun to drive!"

Safety is another major benefit of this very strong construction method. That is partly inherent in aluminium as a material, which absorbs significantly more energy per kilogramme of material weight than steel when it is deformed. But the strength advantage doesn't only apply to high-speed impacts, it also means lower-speed accident repair costs are kept to a minimum. The reduction in the number of joints in the all-new Jaguar XK further increases strength, and the front of the body is protected by easily replaced 'crush cans' that absorb the energy in impacts up to 15kph.

The all-new Jaguar XK's all-aluminium doors are each over 6kg lighter than an equivalent steel door and their mountings are significantly stiffer, which allows smaller gaps. Mounting the window glass rails directly to the aluminium castings at the front and rear of the door gives better sealing from the frameless layout, and an impressively solid sound and feel when closed.

The all-aluminium Liftback rear door is strong, light and simple to operate. Once it has been lifted manually through the first 20 per cent of its opening arc, gas struts lift it the rest of the way.

With lower weight and higher strength, Lightweight Vehicle Technology is the starting point for improved performance, safety, refinement, economy, emissions performance and driving dynamics in the new Jaguar XK.


 
JAGUAR XK POWERTRAIN

- Latest generation naturally aspirated 4.2 litre V8, develops 300bhp (224kW) SAE / 298PS (219kW) EEC and 310lb ft (420Nm) SAE / 303lb ft (411 Nm) EEC of torque
- Engine satisfies Euro 4 emissions requirements and features Exhaust Gas Recirculation
- New Jaguar Sequential Shift 6-speed automatic transmission incorporates steering wheel-mounted gearchange paddles

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