The bump in dimensions provides the basis for a 17mm lengthening of the cabin, allowing incremental increases in rear leg room and additional boot space. Yet despite growing in size, the new S5 Sportback boasts a commendable 85kg reduction in weight over predecessor, at 1660kg.
Under the bonnet is a new turbocharged 3.0-litre V6 petrol engine. The 60deg unit forms part of the modular EA838 range of engines, the most powerful of which is destined to power the upcoming RS5 Sportback. Innovations include Audi’s patented valve lift system, with continuously adjusting camshafts and centre-mounted spark plugs contributing to improved combustion efficiency and improved response.
With 349bhp, the new engine delivers 21bhp more than its predecessor, but more important is a 45lb ft lift in torque, to 369lb ft, produced between 1380 and 4500rpm.
The S5 Sportback receives an eight-speed torque converter automatic gearbox as standard, with a Tiptronic shift function and steering wheel-mounted shift paddles.
Drive is sent to all four wheels via the latest version of Audi’s Torsen torque-sensing quattro four-wheel drive system. Under normal conditions, 40% of drive is sent to the front wheels and the remaining 60% to the rear, but depending on prevailing grip, up to 70% of drive can now be sent to the front or up to 85% to the rear. A sport differential, which continuously varies the amount of drive to each individual rear wheel, is available as an option.
What's it like?
The initial impression is one of thoroughness. Its design may lean heavily on that of its predecessor but the subtle styling nuances and overall precision in the fit of its frameless doors is quite superb.
The attention to detail continues in the cabin, which carries a combination of materials and controls of a much higher perceived quality than those found in its BMW or Mercedes-AMG rivals. The front sports seats offer plenty of lateral support and a reasonable amount of adjustment and all-round visibility is sound, although the C-pillars sometimes prove an impediment during quick over-shoulder glances.
The dashboard and wide centre console house the latest evolution of Audi’s MMI infotainment system. A 7.0in centre-mounted display is standard, although the 12.3in Virtual Cockpit and head-up display unit of our test car remain options.
Well-shaped rear door apertures provide good if not excellent access. Adults can be accommodated in the back, although the heavy curvature of the roof means head room is a little limited. For the record, Audi claims an added 24mm of knee room and 11mm of extra shoulder room. An electronically operated tailgate is standard, while the boot has a 15-litre increase in capacity over its predecessor, at 480 litres. With 40/20/40 split rear seats folded, this can be extended to 1300 litres.
Positive impressions continue as you get under way. With greater torque arriving earlier in the rev range, the S5 Sportback proves highly flexible and responsive around town. In lower gears out on the open road it pulls with real earnest when its reserves are unleashed with a heavy nudge of the throttle, propelling the new five-door liftback along with great authority.
An alluring soundtrack accompanies this flexibility and urgency. On light throttle loads there's a raspy exhaust note that grows in volume and intensity, ultimately becoming quite menacing in Dynamic mode on the approach to the 7500rpm redline.