"The crown of the Q range" debuts at the Detroit motor show. Like it?

And here it is – the biggest number ever attached to an Audi Q model. And that’s pretty fitting, given the size of the thing. Meet the Audi Q8.

Audi says the Q8 is about five metres long, two metres wide, 1.7 metres tall and has a three-metre wheelbase – almost exactly the same as a 2017 Range Rover – but unlike the Range Rover, the Q8 will be a “luxury lounge for four”. We can think of cheaper ways to get four people around in comfort.

It’s described by Audi board member Dr Dietmar Voggenreiter as “the crown of the Q range”.

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“This should be the Q car comparable to the A8,” he tells Top Gear. “The 8 always signifies the high-end cars – the A8, the R8, and now the Q8. The Q7 is more versatile and function orientated. This is more sporty, more expressive, and gives you a different image compared to a Q7.”

To make sure such a vast vehicle isn’t slower than an asthmatic tortoise, Audi’s combined a 333bhp version of its 3.0 TFSI with a plug-in hybrid system that’s good for a combined 442bhp and 516lb ft. The practical upshot of this particular combination of electricity and dino-juice is zero to 62mph in 5.4 seconds, a top speed of 155mph and a frankly absurd fuel consumption of 122mpg. It also means a theoretical range of 621 miles and so few carbon dioxides that it could even tempt buyers out of rattly, polluting diesels. We can dream.

The 17.9kWh battery allows for an electric range of about 37 miles, and it’ll take two and a half hours to recharge completely – if you have a high-power outlet. The Q8 will have driving modes that allow you to spend or save battery juice as you see fit, or you can leave the decision to the hybrid system itself.

Adaptive air suspension should make for a pretty plush ride, and also allows for 3.5 inches of lift, should you ever encounter the kind of conditions that SUVs are designed to tackle. You’ll be able to firm up the suspension, if you so choose, and tackle corners with gusto, thanks to a brake controller that brakes the inside wheel to keep a tight line in sharp corners. The meaty, 20-inch ceramic discs will also take care of the ‘Oh sh…’ moments, and generators will recoup kinetic energy into the hybrid system in most other cases.

Inside, expect Audi-style layers of leather and pathological attention to the fit and finish. There’s also the excellent virtual cockpit system, head-up display and more touchscreens than the wall of a Carphone Warehouse. It seems that the days of the mechanical switch are numbered, folks. Audi says the dashboard “resembles the stern of a sailing yacht”, but we’ll leave the judgement up to you. The new A8, due in June, will get a matching interior to the Q8.

If the concept is enough to pique your interest, you’ll be glad to know that a production version will go on sale in 2018, mostly unchanged from the concept you see here.

So, given that it’s a four-seater, is it likely to be your new family car?

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