Both the XK8 and XKR are electronically limited to a maximum of 155 mph, lower than the top speed of its predecessor. The XK8 heralded a change in direction for the company, resulting in the S-Type and X-Type.
The XK8 and XKR come standard with 18-inch alloy wheels, and 19 and 20-inch wheels are available for additional cost. A navigation system and self-leveling xenon headlamps come standard with the XKR and as options for the XK8. Jaguar's Adaptive Cruise Control is an optional feature available on both models. Both come with all-leather interior, burl walnut trim, and side airbags. Jeremy Clarkson, during a Top Gear, a UK motoring magazine/TV show, test-drive, likened the interior of the original XK8 to sitting inside Blenheim Palace. In 2005 the grille design of the XKR was refreshed.
Only 600 XKR Silverstones were made, in celebration of Jaguar's return to F1 racing in 2001. It featured a Platinum paint finish, high-performance package (with the same engine as the standard XKR, but improved transmission, suspension and brakes), 20" Silver BBS "Detroit" wheels and a custom interior.
Built to celebrate the centenary of Jaguar's founder, 500 'XKR 100' coupés and 500 convertibles were made in 2002. The XKR 100 featured an Anthracite paint finish, Recaro seats, 20-inch BBS alloys, Brembo brakes, and custom interior.
The convertible-only Portfolios were produced in 2004 exclusively for the US market. Of the Portfolio models, 100 featured unique Red paint with matching Recaro sports seats and interior, whilst the remaining 100 had Blue paintwork and interiors.
There is also a 2008 Portfolio model planned which will be available worldwide, featuring the most powerful brakes featured on any production-line Jaguar.