Jaguar's distinctive design and luxury remains largely unchanged for 1999. The Jaguar XJ sedan is defined by four trim levels topped by a 370-horsepower supercharged XJR. Once again in 1999, the 2+2 passenger Jaguar XK8 is offered as a coupe or convertible. A beige soft top is now available on the XK8 convertible model as is two new exterior colors. The 4.0-liter V-8 engines used by both the XJ and XK8 gain modest upgrades for 1999. Dual-tipped platinum spark plugs are now installed and the engine management system have been retuned. Despite the minor reworking on the V-8 powerplant for 1999 Jaguar products, horsepower and torque remains unchanged.