Audi SQ8 – the big, fast Audi to end all big, fast Audis

The range-topping SQ8 boasts a 4.0-litre V8 TDI, the same as that of the slightly smaller SQ7. With 435PS (429bhp) and 900Nm (663.8lb ft) of torque available between 1,250 and 3,250rpm, despite its size, the SQ8 can accelerate from nought to 62mph in just 4.8 seconds, before reaching its electronic limiter at 155mph.

Twin turbochargers sit within the engine’s V, operating sequentially, with only one charger active at low speeds before the second kicks in at 2,200rpm. An electrically powered compressor (EPC) assists the turbochargers when starting off and during low speed acceleration, all but eliminating the dreaded turbo lag and ensuring consistently strong power delivery.

Powering the EPC is the 48-volt electrical system, with a compact lithium-ion battery.  Helping to feed this battery is the mild hybrid system (MHEV), which regenerates up to 8kW of power during deceleration. And if, for example, you lift off the accelerator between 34mph and 99mph, the car can either recuperate energy, travel with the engine at idle, or coast with the engine completely deactivated for up to 40 seconds.

Power is transferred to all four wheels via an eight-speed Tiptronic transmission and Audi’s quattro all-wheel-drive system, while Vorsprung models get the quattro sport rear axle differential, which actively distributes torque between the rear wheels in order to prevent over- and understeer. 

The seven mode Audi drive select dynamic handling system features as standard on both models, as does adaptive air suspension, which changes the ride height by as much as 90 millimetres. The Vorsprung also receives active roll stabilisation plus all-wheel-steering, which turns the rear wheels in the opposite direction to the front at low speeds to aid manoeuvrability, and with them at speeds upwards of 37mph to increase stability.

From the outside, it’s immediately obvious that the 3-metre-long SQ8 is a very big car. Underbody protection peeps out at both front and rear, while large air inlets and diffusers, plus HD Matrix LED headlights, are immediately obvious. Vorsprung versions receive black details around the bumpers, grille and the side windows.

In the cabin, sport seats with chunky side bolsters are standard, while in the Vorsprung they incorporate climate control and massage functions. The practicality minded will be delighted to know that the boot is huge, as folding the three rear seats forward presents 1,755-litres of storage capacity, which diminishes to 605 litres with the seats in place. An electrically operated boot features as standard.

The cabin is finished primarily in diamond stitched black Valcona leather upholstery, but the seats and armrests can be trimmed in grey or red, with contrast stitching. The standard model gets aluminium effects throughout the cabin with the option of an oak grey finish, while the Vorsprung boasts – you guessed it – carbon fibre.

The SQ8 TDI has two large touchscreens with the upper featuring the infotainment and navigation systems, while the lower is used for managing the air conditionin and other convenience functions. There’s also an intuitive voice control feature, plus Amazon’s Alexa, which can be used to place orders and source information. Meanwhile, the driver can connect to the car using the myAudi app.

City driving is made safer by cross traffic assist front and rear, exit warning and active lane assist, all of which are standard on the Vorsprung and optional for the base model, while adaptive cruise assist (combining adaptive cruise control, traffic jam assist, and active lane assist) is an option on both.

One interesting feature, available on the top-of-the-line MMI navigation system, is a traffic light information function which, when the infrastructure becomes available in cities across Europe, will allow the driver to select a speed to match the next green-light phase, making for more economical driving.

Behind all these systems lies the central driver assistance controller, or zFAS for short, which uses five radar sensors, five cameras, and twelve ultrasound sensors to constantly calculate the vehicle’s environment, enabling the assist systems to react precisely and instantly.

The order books for the new SQ8 TDI will open next month, with prospective buyers able to choose either the standard model or the high spec Vorsprung form.