Jaguar XJR X308 Supercharged V8
The Jaguar XJR in X308 specification represented the pinnacle of the classic XJ saloon series, combining a potent supercharged V8 engine with a chassis developed to exploit its considerable power. Introduced for the 1998 model year, the XJR offered a compelling alternative to the BMW M5 and Mercedes-AMG E-Class for buyers who valued discretion alongside performance.
The heart of the XJR was the AJ-V8 engine, Jaguar's first production V8, equipped with an Eaton M112 Roots-type supercharger and water-to-air intercooler. This combination produced 370 horsepower at 6150 rpm and a substantial 387 lb-ft of torque at 3600 rpm. The supercharger provided instant throttle response without the lag associated with turbocharging, delivering a relentless surge of acceleration that could catch the unwary by surprise.
The ZF five-speed automatic transmission was calibrated for the XJR's sporting character, with a sport mode that held gears longer and delivered crisper shifts. The CATS (Computer Active Technology Suspension) system featured adaptive dampers that continuously adjusted to road conditions and driving style, providing an exceptional balance between comfort and control.
Brembo four-piston front brake calipers provided reassuring stopping power, necessary given the XJR's ability to reach 155 mph (electronically limited). The suspension was lowered compared to the standard XJ8, with firmer spring rates and revised anti-roll bars. Wider 18-inch alloy wheels with 255-section tyres completed the dynamic package.
Exteriorly, the XJR was distinguished by subtle mesh grille inserts, a small boot lip spoiler, lower body extensions, and unique alloy wheel designs. The overall effect was of quiet menace rather than overt aggression, in keeping with the Jaguar tradition of understated performance. The interior featured sport seats, perforated leather, and additional XJR badging.
In its day, the XJR was praised by journalists for its remarkable combination of straight-line speed, comfortable ride, and the distinctive character that set Jaguars apart from their German rivals. The supercharged V8 note was unique and addictive, a refined growl that became a snarl under full acceleration.
Approximately 12,500 XJR X308 models were produced. Today, the car represents extraordinary value, offering genuine supercar-baiting performance with an interior ambiance that shames many cars costing far more. As awareness of the X308 XJR's qualities grows among enthusiasts, values are beginning to firm from their historic lows.
The supercharger is generally reliable but check for boost leaks and intercooler condition. The Nikasil bore liner issue affected early AJ-V8 engines; ensure the engine has been retrofitted with steel liners or is a later production unit. Check CATS suspension for proper operation; replacement dampers are expensive. The ZF gearbox is robust but requires regular fluid changes. Rust can affect sills and subframe mounts despite improved corrosion protection. Electrical issues are common on high-mileage cars. Low-mileage examples with full service history represent the best buys.
The X308 replaced the X300 series for the 1998 model year. The XJR specification was available throughout the X308 production run. A 100th Anniversary edition was produced in 2000 with special trim. The final X308 XJRs were produced in 2003 before the aluminum X350 series arrived.