What is it?
A new – and slightly quicker – version of the supercharged Jaguar XJ Supersport. Power remains the same, but the Speed pack brings some minor cosmetic changes and a more permissive speed limiter – now raised from the standard car’s 155mph to 174mph.
Mostly it’s the familiar XJ Supersport – one of our favourite big saloons – with power coming from a supercharged 5-litre V8 engine putting out 510 bhp. Changes are limited to a revised bodykit, which is claimed to reduce aerodynamic lift by 40 percent when compared to the standard car, plus unique wheels and red brake calipers. The tyre pressure monitoring system and software for the digital speedometer has been tweaked to take account of the potential for running at sustained higher speeds.
How does it drive?
With no substantive changes to suspension or powertrain it’s no surprise that the Speed Pack equipped Supersport drives pretty much exactly the same way as its standard sister – below 155mph, at least.
That means a brilliant engine, effortless any-speed urge and a chassis that does an excellent job of keeping the XJ’s serious bulk in check. Refinement is impressive, too – and the long-wheelbase version doesn’t seem to come with any significant dynamic cost over the standard car.
On a convenient stretch of derestricted Autobahn the Speed Pack proved itself, blasting through the 250km/h mark at which the standard limiter stops play and pulling strongly all the way to an indicated 287km/h (178mph) – and to judge from the sensation of acceleration being constrained when it gets there, it feels like it could go comfortably beyond that if left to its own devices.
How does it compare?
That really depends how often you want to take your XJ to the Autobahn – or a derestricted test track. The Speed Pack adds £3495 to the price of a long wheelbase Supersport and £3700 to a standard wheelbase version.
Anything else I should know?
A lesser Sport Pack, which brings the same visual bling, is available on the rest of the range, costing £1900 on the V8 and £2630 on the 3-litre diesel.