This Range Rover Sport might, more or less, look like any other on the road today and that’s because, well, it is. The significant difference is hidden away beneath its long bonnet, where the firm’s new 3.0-litre straight six petrol engine lurks.

The technology that this engine showcases will play a significant role in the future of the firm as it finds its way into many of the manufacturer’s models.

Jaguar Land Rover has announced that by 2020 every model in its range will either include electrification of some kind of be a full-fat electric vehicle. We’ve already seen what the company can do at one end of the scale with the excellent iPace, now it’s time to see how the mild hybrid system in the HST measures up.

The adoption of a straight-six is, say engineers, simply because the in-line configuration is inherently smoother than a Vee and Jaguar was fitting its cars with the former long before V8s became the norm.

More significantly, however, is the inclusion of a 48v electrically-powered supercharger – plus a more conventional turbo – and its mild hybrid system, which also uses a 48-volt battery.

Together these elements help the 3.0-litre engine generate an impressive 395bhp and 550Nm of twisting force but, says Land Rover, what really defines the engine in the HST is its smoothness, allied to its much improved efficiency and economy.

A fuel economy figure of 30.5mpg on the combined cycle and emissions of 213g/km might not appear all that impressive, but when you take into consideration that the HST weighs about two-and-a-half tonnes and still manages a 0-62mph time of 6.2 seconds and a top speed of 140mph, those numbers are significantly more impressive.

It’s all clever stuff under the bonnet, with the electric supercharger plugging the gap where you would usually be waiting for the turbo to spin up to speed, effectively eliminating turbo lag. The hybrid system also recharges the battery under braking or when you lift off

Driving the HST proves that Jaguar Land Rover’s engineers know their beans. The engine is smooth and strong, and like a fine espresso, it has a bit of a kick. Power delivery feels very natural and linear despite, or because of, the wizardry going on beneath the bonnet. There is no noticeable turbo lag.

It handles remarkably well for a tall, heavy car with a high centre of gravity. Body roll is kept in check and there is lots of grip to exploit helped, of course, by the permanent four-wheel-drive transmission. What is particularly impressive is the way the car seems to shrink around you, it’s poise and agility masking its size and mass with considerable success.

The fit and finish in the cabin is immaculate. You’ll also find some design features unique to the HST, such as the Alcantara trim on the steering wheel – which is wonderfully soft to the touch – and the gear lever. The seat trim is also bespoke.

The HST is equipped with the Touch Pro Duo system that debuted on the Velar. As the name loosely suggests there are two screens, one mounted in the top of the dash that rotates through 30 degrees to provide a better viewing angle when you start the engine and provides all the typical multimedia functions and another beneath it that operates the air con, heated seats and vehicle settings through a series of capacitive buttons and dials.

It looks terrific and works well but is an absolute fingerprint magnet.

Externally the HST resembles any other Range Rover Sport, which is no bad thing because, in this reviewer’s opinion, it is easily the most handsome premium SUV on the market. There are, however, a couple of unique style points: It comes with a choice of two new alloy wheel styles and highly conspicuous brake callipers painted in a vibrant red.

If there is one area that the HST disappoints, and it’s just a minor point, it’s the engine note, particularly at the top end of the register. It isn’t that it ever sounds stressed, nor coarse, it’s quite the opposite. It’s always muted, just a little too restrained. You can, rightly, argue that in a luxury limo that’s precisely what you what but I enjoy an appropriately musical backing track to accompany my motoring.

The HST is more than just another model in the Range Rover, it’s a glimpse into the future of the company and, based on the car reviewed here, it should be a bright one. The HST is smooth, fast and reasonably economical all wrapped up in a typically luxurious and comfortable – as well as capable – package.

Range Rover Sport P400 HST

Price: £81,250

As tested: £89,455

Engine: 3.0-litre 6-cylinder petrol

Transmission: 8-speed automatic

Max power: 400hp

Max torque: 550Nm

Max speed: 140mph

0-62mph: 5.9sec

WLTP low: 27.4mpg

WLTP high: 24.9mpg

Emissions (CO2): 209g/km

For more information visit www.landrover.co.uk