On sale from spring 2003, the all-new XJR, already acclaimed for its stunning appearances in polished aluminium at the recent Paris and British motor shows, provides the blueprint for future intelligent manufacturing of large saloon cars.
The XJ saloon is the bedrock on which the Jaguar of today is based. Seven generations of XJ, from the very first XJ6 unveiled by Sir William Lyons in 1968, to the all-new model that made its public debut in September 2002, have taken the mantle of the definitive Jaguar saloon. Total production since the first XJ model in 1968 is now comfortably past 800,000 cars, more than half of all Jaguars ever built.
An Aluminum Monocoque
With an aluminium monocoque structure that brings outstanding weight savings compared to conventional steel cars, the new XJ is lighter than the outgoing model by up to 200kg. This brings marked improvements in fuel economy and emissions and also provides excellent safety and crash protection. In addition, the lighter vehicle weight allows for increased performance across the board and great agility.
The new XJ’s body structure comprises pressings of sheet aluminium combined with aluminium alloy extrusions and aluminium castings. Jaguar’s engineers adopted the proven construction techniques of the aerospace industry to assemble this structure and in volume production, the new Jaguar XJ represents an industry-first use of rivet-bonding construction for an aluminium-intensive monocoque body.
Rivet-bonding uses self-piercing rivets and epoxy adhesives for strength, robustness and durability when joining aluminium pressings. The adhesives applied robotically during assembly, heat-cure to optimal strength during the vehicle painting process. Approaching 3,200 rivets are used in the construction of the new body.
The body of the new XJ is significantly stiffer, by 60 per cent, and lighter by 40 per cent than its predecessor. The strength of its architecture also represents a groundbreaking advance in crashworthiness.
The supercharged version of the 4.2-liter V8 is the heart of Jaguars performance flagship, the XJR. This achieves a peak horsepower of 390 bph at 6100 rev/min, a 33 percent increase over the normally aspirated variant. At least 86 percent of peak torque is available from 2000 rev/min to a peak of 399 lb ft (SAE) at 3500 rev/min. The supercharged 4.2-liter engine delivers eight percent greater power and five percent more torque than the previous 4.0-liter AJ-V8.
Forged, oil-cooled pistons, high fin-density intercoolers and a unique twin fuel pump system are fitted to handle the increased output. The mechanically driven Eaton supercharger has excellent boost characteristics which, combined with twin intercoolers, results in outstanding performance under all driving conditions. The Eaton supercharger spins 5 percent faster than the unit on its 4.0-liter engine predecessor.
New front and rear suspension systems, .with the refinement of standard air suspension and enhanced Computer Active Technology Suspension (CATS) adaptive damping, take ride comfort and vehicle handling to new levels.
The XJ’s air suspension system uses air spring/damper units in lieu of the coil-spring/damper units of a traditional system. Height sensors at the four corners of the car feed vehicle height data to an electronic control module in the boot and on de-restricted roads, the system automatically lowers the XJ’s ride height by 15 mm at 160 km/h (100 mph). This improves aerodynamic efficiency, vehicle stability and fuel economy during high-speed cruising.
A compressor located behind the front bumper beam feeds compressed air toa .16 cu ft. reservoir located in the XJs trunk under the spare wheel. Here, it is stored at a maximum pressure of 218 psi and distributed to the individual spring/damper units by a solenoid-driver valve block.
Height sensors at the four corners of the vehicle feed vehicle height data to an electronic control module in the trunk. On de-restricted roads, the system automatically lowers the XJs ride height by over 15 mm at 100 mph. This improves aerodynamic efficiency, vehicle stability and fuel economy during high-speed cruising.
Brembo brakes for XJR
Jaguar XJR features a Brembo braking system, designed to match the performance capabilities of this supercharged model. XJR models are also fitted with lightweight steel-braided brake hoses. Brembos monobloc calipers – developed from racing technology and manufactured from single aluminum castings – provide high levels of stiffness and low weight for optimal high-speed braking, while the four piston design facilitates a larger pad area and helps maintain uniform pressure distribution across the pad surfaces.
At the front, 14.4 x 1.26 ventilated discs are mated with Brembo aluminum, four-piston monobloc calipers embossed with the Jaguar R Performance logo. Solid rear discs (13 x .59) are fitted with aluminum two-piece, fixed, opposed four-piston calipers. The parking brake has a single-piston floating caliper.
The new Jaguar XJR recorded stopping distances of 118 ft from 62.5 mph to zero in testing. This was up to 14 percent more efficient than key luxury competitors and is another advantage of the XJ’s lightweight vehicle architecture.
The new Jaguar XJR features an exclusive interior design that reflects its performance capabilities. A unique seat design with 16-way power adjustability for the driver and front-seat passenger, has more pronounced lateral bolsters for the back and thighs to provide exactly the right balance of support and comfort.
Additional standard features on the XJR include heated front and rear seats, heated wood and leather steering wheel, power rear sunblind, and Alpine audio system, and radar-based adaptive cruise control (ACC).