Jaguar has been on the offensive recently, with a range of SUVs and smaller sedans aimed at the mass market. Don't think the company has forgotten its roots in powerful, luxurious sedans though. Packing a supercharged V8 under the hood, and enough leather inside to make PETA activists weep, the XJR 575 is a typically British take on the modern super sedan.

Perhaps the most important part of any super-sedan is the engine, and Jaguar has gone all-out to make sure the XJR 575 has a special powertrain under the hood. The name is a nod to the 575 metric horsepower (567 hp/423 kW) of power it produces, while peak torque is pegged at 700 Nm. Combined with the standard automatic gearbox, it shoots the biggest cat to 100 km/h (62 mph) in just 4.4 seconds on the way to 300 km/h (186 mph).

Will many owners ever come close to hitting that top speed? Probably not, but huge power and torque also mean effortless performance around town, or at regular highway speeds. Just because you have all that grunt doesn't mean you need to use it all the time.

It's never going to be a sharp handler like the XE SV Project 8, but the XJR 575 should strike a decent balance between long-haul comfort and flat backroad blasting. Adaptive dampers adjust themselves up to 500 times per second, based on the throttle position, brake pedal activity and information from the standard air suspension.

Extra grunt and smart suspension is always a good thing, but the XJ was also in dire need of a technology refresh. The entire range has been treated to an injection of active safety features for 2018. Auto-emergency braking, lane-keeping assist and a driver monitoring system are all standard, but the Jaguar flagship is miles behind the new Audi A8 when it comes to semi-autonomous driver assists. Given it was first launched eight years ago, that's no great surprise.

From the outside, there's not much to differentiate the 575 from the standard XJR. There are more pronounced air intakes in the front bumper and a rear lip spoiler, two new paint colors, and the wheels have been painted black, but that's about it. The tweaks are more pronounced inside, where the standard seats have been replaced with quilted units finished with unique stitching.

"This is a performance vehicle, but that doesn't mean we have had to cut any corners when it comes to comfort or design," says Ian Callum, Head of Design at Jaguar. "Jaguar is the standard bearer for interior refinement and the XJR 575 is no different. It can go very quickly, but it does so with the serene comfort customers expect from a Jaguar saloon. That makes this a very special car indeed."

Check out the new XJR 575 in action below.

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