Luxury SUV packs 500bhp

Sporting version of Audi’s ultimate SUV switches from a diesel V8 to a petrol one

Audi is at its best when using the best technology at its disposal to make the most accomplished luxury cars it can. Trouble is, when it makes arbitrary rules about the kind of engines its lower-order hot cars should use and expanding into vital developing market areas, its most direct route to ‘Vorsprung durch Technik’ isn’t always open.

Thankfully, rules are made to be broken, and even when Audi first started switching its S models from petrol to diesel a few years ago (to reduce their average CO2 emissions), it excepted the SQ2, S3, S8 and TTS. And now, as it introduces the SQ7 and SQ8 SUVS to North America, both have switched from diesel to petrol.

For the SQ8, that means ditching a 429bhp 4.0-litre mild-hybrid V8 in favour of the Porsche-designed EA825 4.0-litre twin-turbo V8 that powers many Porsches and Bentleys, the odd Lamborghini and even some of Audi’s even-faster RS models.

In the SQ8, it produces a slightly detuned but still very hearty 500bhp. This slashes the 0-62mph dash time from 4.8sec to 4.1sec, but it also makes the official fuel economy tumble from 36.2mpg to 22.1mpg.

Clearly there are some who were well served by the SQ8 TDI but won’t be as much so by the SQ8 TFSI. Even so, Audi claims most of the growth at the top of the luxury SUV market is being fuelled by petrol engines – and this is certainly a good one.

It can change from super-refined through distantly mellifluous to growlingly rich and menacing as you cycle through the modes. It has great throttle response, it revs keenly and it has more than enough grunt to keep life interesting in a 2.3-tonne SUV.

The character of the V8 is a pretty good match for the SQ8’S handling. It’s really effective in so many ways, although super-capable, filtered-feeling and somewhat aloof rather than entirely involving. It can cruise in limo-like comfort but also can claw its way around slippery corners as level, fast and securely locked onto its line as a four-wheel-drive hot hatch.

The range-topping Vorsprung adds height-adjustable air suspension, adaptive dampers, mechanically torque-vectored 4WD, all-wheel steering and active anti-roll bars.

In a car that feels like a traditional Audi really loaded with tech, all this combines for impressive dynamic versatility and lots of luxury appeal.