Jaguar provides a great package

Jaguar XJ
Jaguar XJ

The Jaguar XJ 3.0 SC is going to remain a minority pick in a range where diesel remains king but in improving the fuel consumption from around 25mpg to around 30mpg compared to its 5.0-litre V8 predecessor, it will become relevant to a good deal more potential buyers. With 340bhp on tap, it’s not going to feel slow.

I know what you’re thinking. It’s easy to spout on about improved efficiency when you’ve just replaced a 510PS 5.0-litre V8 with a 340PS 3.0-litre V6. Eggs are not really being compared to eggs.

Well, they are. They’re just smaller eggs - but you see what I mean.

And it’s true, the 3.0-litre car just can’t compete with the bigger engine’s sheer urge, taking 5.7 seconds as opposed to 4.7 seconds to get to 60mph.

Let’s think about that for a minute though. Making the Jaguar XJ go that second faster to 60mph rendered it effectively unsellable in the UK due to its fuel thirst. And 5.7 seconds to 60mph? In a car this big? That’s not hanging around. It’s still quick enough to keep the latest Porsche Boxster honest.

This engine makes almost 127PS per litre, which is the highest specific output of any Jaguar engine, so it’s really singing for its supper.

It’s fitted to both the XJ and XF, and it’s also the engine that’s fitted to the F-TYPE sports car that stole the limelight at the 2012 Paris Motor Show.

Jaguar has also implemented a number of suspension improvement for this latest model. There are re-calibrated spring and damper tunes as well as remapped damper software - offering enhanced ride isolation and passenger comfort on all road surfaces. That trademark Jaguar waftability certainly hasn’t been sacrificed on the altar of efficiency.

The XJ’s front end owes a lot to the XF but the real drama is at the rear where Jaguar has gone for an elegant but bold treatment.

The C-pillars are blacked out to look like an extension of the rear screen and the tail lights arch up around the rear haunches into the line of the boot lid. The lighter paint colours show off those C-pillars more effectively and buyers who aren’t persuaded by them can choose black paint, limiting their impact.

Let’s get one thing clear. Replacing a 5.0-litre supercharged V8 with a 3.0-litre supercharged V6 is not a like-for-like swap. Less in this case really is less. You get less power and acceleration, but 340PS should still be more than adequate. More importantly, you get less of a fuel thirst, less emissions, less depreciation and less of an insurance bill come renewal time. On the balance of things, that seems a more than fair trade.

While the prospect of a Jaguar XJ that can accelerate to 62mph in less than six seconds yet return a 30mpg fuel economy average seems beguiling, this is still a premium vehicle with premium vehicle running costs.

That said, when judged against its rivals, this XJ 3.0 SC looks a great package. The shape still looks brilliant and quality and aftersales improvements in recent years have seen Jaguar overtake its German rivals in customer satisfaction surveys. It’ll remain outshone by the diesel car here in the UK, but at least this is now a variant you can make a really strong case for buying.