There’s always a slight twinge of despondence when a carmaker decides to can a charismatic V8 in favour of a smaller, more efficient engine. This feeling is especially pronounced when the marque in question is Jaguar and the model its range-topping XJ.
Yes, the naturally aspirated 5,0-litre, an engine much loved by a number of CAR testers for its flexible nature and pleasingly burbling soundtrack, has been nixed and a new 3,0-litre supercharged V6 has taken its place.
Can this engine fill the shoes left by its larger predecessor, or does less displacement mean less enjoyment?
The new engine is based on the 5,0 litre’s all-alloy block and em- ploys similar technologies such as variable-valve timing and direct fuel injection. Nestled between the cylin- der banks is a Roots-type twin-vortex supercharger with a water-cooled intercooler, which is more compact than that of the supercharged 5,0-litre V8.
Although it’s two cylinders shy of its predecessor and its outputs around 12 per cent down, the 3,0-litre’s 250 kW and 450 N.m of torque do a great job of propelling the XJ. However, while the engine feels satisfyingly strong in the mid-to-upper rev range, there is a slight hesitancy off the line and under aggressive acceleration that you’d normally not expect of a supercharged powerplant.
We initially thought it could be a symptom of the car’s more eco-friendly, and therefore less rev-hungry, default drivetrain setting, but switching to the sportier dynamic mode did little to alleviate this.
The only other potential culprit could be the Jaguar-tuned eight-speed ZF transmission. Even so, in 90-odd per cent of driving conditions, the ‘box was smooth and assured in its operation.
Jaguar went to great lengths to ensure that the new engine takes up the V8 mantle of smoothness and refinement by implementing a series of counter-rotating front and rear-balancer weights. It works a treat; the drivetrain proves silky smooth and engine noise is relegated to a muted snarl only under hard acceleration.
Where the 3,0 V6 SC really comes into its own is in terms of fuel economy. Compared with its forebear’s near-14,0-litre/100 km thirst, the new engine is decidedly frugal, returning 9,2 litres/100 km on our mixed-use fuel route.
Otherwise, the tenets of the XJ experience remain intact. There’s still that taut, eye-catching bodywork and a cabin that, despite some garish details and tight dimensions, is one of the most interesting in its segment.
The driving experience also remains undiluted; the big cat exhibits the sort of dynamic poise and feedback that you’d never expect of a grand saloon, albeit at the price of the ride, which is a touch more fidgety than that of its German rivals.
Test Summary
The entrance of the V6 is a bittersweet affair. However, as sad as the 5,0-litre V8’s passing is, the new engine hasn’t let the side down. Those previously compelled by the big Jag’s unconventional charm, but repelled by its thirst, could well be drawn to this particular model’s neat balance of power and frugality.
