JAGUAR XKR CHASSIS, SUSPENSION AND BRAKES

To ensure optimum ride and handling, Jaguar XKR's springs and dampers are uprated compared to the normally aspirated XK. The front spring rate is increased by 38% and the rear spring rate by 24%. Allied to the Servotronic steering system, which has also been tuned both mechanically and electronically to give the steering more weight and even greater response, the suspension ensures confidence-inspiring handling without any loss in refinement and comfort levels.

Because of the inherent strength and stiffness of the chassis, the only significant addition to the XKR's structure is an additional rear suspension brace mounted between the rear damper towers to accommodate the significant increase in rear spring rate. This also allows the Convertible to utilize the same dynamic settings as the Coupe model.

The Computer Active Technology Suspension (a two-stage adaptive damping system that ensures the optimum balance between ride and handling) and new switchable Dynamic Stability Control with Traction Control System (Trac DSC) have also been recalibrated to cope with the additional power of the supercharged engine.

As significant to Jaguar XKR as the increases in power and torque are the major improvements in strength and weight thanks to its advanced all-aluminum architecture. Unique in the industry as a complete aluminum monocoque body structure, as distinct from an aluminum spaceframe with separate aluminum exterior panels, its properties come from both the way the bodyshell is designed and constructed, and the use of new joining technologies.

In fact, the new Jaguar XKR's aluminum chassis is significantly lighter and stiffer in both Coupe and Convertible form than the steel model it replaces. The Coupe chassis is over 30 percent stiffer than the previous XK, while the Convertible is over 40 percent stiffer. As a consequence, the XKR accelerates faster than the previous model, while offering high levels of safety, reduced noise and vibration intrusion, and improved ride and handling characteristics thanks to improved suspension dynamics.

In Convertible form, the BIW weight, at just 633lb (287kg), is 19 percent lighter than the previous XKR Convertible.

New, larger ventilated brake discs at the front ensure higher braking performance for Jaguar XKR. The front brake disc diameter has increased from 12.8in to 14.0in (326mm to 355mm), and the thickness from 1.2in to 1.3in (30mm to 32mm), which not only improves the braking performance but also the system's resistance to fade. The braking system also includes four-channel ABS, Electronic Brake Force Distribution, Hydraulic Brake Assist to increase brake pressure during an emergency stop, and Jaguar's Electronic Park Brake function.



POWERTRAIN / DRIVING DYNAMICS

Driving the new Jaguar XKR - exhilaration redefined

The new 420bhp (SAE) Jaguar XKR is a sensational car to drive. With 120bhp (SAE) more power than the normally aspirated 4.2-liter XK, the same strong and stiff aluminum body structure that ensures superb ride and handling, and a six-speed automatic transmission with Jaguar Sequential Shift that is regarded as class-leading in terms of gear-change speed as well as refinement, Jaguar's blend of performance and dynamics reaches new heights with Jaguar XKR.

"Our aim when engineering the new Jaguar XKR was to ensure that the car's character remained balanced despite the significant increase in power over the normally aspirated XK," explains Jaguar's chief engineer, Mike Cross.

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