The chassis is new, too, with a five-link arrangement at the front and back, paired with adaptive dampers (RS Sport suspension with Dynamic Ride Control is an additional option; ditto the RS exhaust system and the traditionally undesirable dynamic steering set-up).
There’s also a transmission change, with the V8’s dual-clutch seven-speed automatic making way for a ZF eight-speed torque converter.
That means the car shares an engine with the second-generation Porsche Panamera 4S, but not an entire driveline – Audi the auto is a tweaked version of the S5’s automatic.
The V6’s output is different, too: Audi has eked out 10bhp more so it can claim to match the outgoing V8’s 444bhp. Peak torque, predictably, is dramatically superior, with the V6 summoning up 442lb ft from 1900rpm. At the same time, CO2 emissions have been slashed by 17 percent.
This being Audi Sport, and an RS model to boot, it naturally looks the business. It signals a mild overhaul of the brand’s styling approach - although with its blistered arches, lacerated air intakes and porthole-big oval exhaust pipes, it establishes a familiar scene. The proportions feel about the same, too, despite the 74mm of additional length, which is predominately donated by the MLB’s larger wheelbase.
The RS5's interior also conforms to type: it's immaculate and brilliantly made and utterly endearing to touch and look at. UK models get Audi’s excellent Virtual Cockpit digital instrument panel as standard, and the test car we drove in Andorra had enough Alcantara on the door cards, steering wheel and gear shifter to neatly distinguish the RS5 from the closely related Audi S5.
Other standard fitments on the RS5 include 19in alloy wheels, LED head and rear lights, an acoustically glazed windscreen and a wealth of Audi’s latest safety technology. Inside there is a pair of Super Sport electrically adjustable and heated front seats, tri-zone climate control, ambient interior LED lighting, and Audi’s MMI infotainment system with an 8.3in display, sat nav, DVD player, 10GB hard drive storage, DAB radio, smartphone integration and a 10-speaker audio system.
Firing up the Audi RS5’s twin-turbo V6
Start-up is slightly less auspicious. Audi Sport has persevered with the soundtrack –boldly equating it to the turbocharged V6 that powered the B5-generation RS4 – but its bass-edged waffle doesn’t cover the sound or reality of two substantial blowers whistling away betwixt the cylinder banks. Volkswagen The engine isn’t necessary captive to the rise and fall of the Sirocco, yet nor is it an unchained melody on the V8’s Richter scale.