Audi SQ7

Three turbos talk the torque and silence debate



STANDING on the Audi SQ7ís seemingly innocent throttle pedal is a bit like watching an A380 take off.

Something tells you this big bird wonít fly, but before you can say ďnine hundred Newton metresĒ the Virtual Cockpit display shows three figures entirely incompatible with the speed limit.

Foot flat, thereís a pause as Audi's weighty 2330kg SUV inhales, followed by a deep V8 rumble and the rushing air of three turbochargers, surging the five-metre lump forward on an almighty wave of torque.

It takes one of the most sophisticated powertrains on sale to manufacture all that thrust.

Thereís a 4.0-litre diesel V8 fed by two sequential, variablevane turbos and a third, electric compressor that can spool to 70,000rpm in 250 milliseconds.

A 48-volt electrical subsystem powers the compressor and there's an optional Dynamic package ($13,500) that includes electromechanical roll stabilisation, four-wheel steering and a sports differential.

In Dynamic mode all systems flex simultaneously. The air suspension drops, steering weights up, and active anti-roll bars tense to minimise lateral bodyroll to one degree for 1G of force.

Its front and back axles feel connected, and thereís monstrous grip, though the artificially flat ride makes it difficult to judge the SQ7ís ultimate limits. Weight transfer in tighter corners exposes its obesity, but the SQ7ís overall agility is bizarre.

All-wheel steering plays a part, adding stability at speed while sharpening slower manoeuvres, but the system is less convincing on challenging roads, where the chassis needs constant wheelwork to trim and adjust the SQ7ís line.

The un-optioned car is purer.

Layer upon layer of computer intervention between input and response make the SQ7 dynamically remote. It is forever relaying signals to solenoids and valves, chassis systems and energy recovery components. Itís a marvel of tech, but ultimate driver appeal is diminished.

Perhaps that is in keeping with the SQ7ís impeccable road manners and refinement. As a day-to-day tool for families, SQ7 loses none of the Q7ís appeal.

Its semi-autonomous assistance will drive for you in slow traffic, it seats seven in luxury, itís economical, and in Comfort mode the air suspension slackens and active anti-roll bars decouple to let the big unit stop sucking in its gut and relax.

As a demonstration of whatís possible, the SQ7 is astonishing. And as a conversation starter at the pub, three turbos are hard to top. low ry, omfort sion ars p n s s

We have a response

These days turbo lag is mostly pretty minimal, yet Audiís engineers clearly believe turbo throttle response needed improvement, hence the electrically powered compressor (EPC). In simple terms, the EPC works to force air into the first of the SQ7ís two sequential turbochargers. The theory is the compressor can get the turbo working from idle speed, thus eliminating the dreaded turbo lag.

Model Engine Max power Max torque Transmission Weight Economy 0-100km/h Price On sale Audi SQ7 3956cc V8 (90į), dohc, 32v, TTD 320kW @ 3750-5000rpm 900Nm @ 1000-3250rpm 8-speed automatic 2330kg 4.9sec (claimed) 7.2L/100km $153,616 Now Remote steering; expensive options; weight; yearns for autobahns PLUS & MINUS Refinement; performance; technological superstardom; quality