Out goes the naturally-aspirated 4.2-litre V8 of the old Audi RS 5 for a lighter, just as powerful 2.9-litre V6. The 'downsized' RS 5 promises a lot, but it's got a tough fight on its hands against its usual foes.
In the metal
Audi does good-looking cars, especially those wearing RS badges. The Audi A5 Coupe is a beautifully proportioned car in standard guise, but add some flared wheel arches (under which 19-inch alloys reside - or more likely the optional 20-inch rims), a jutting front 'egg crate' grille and a pair of oval exhaust finishers so huge you could kick a rugby ball down them and the RS 5 wears its intent with pride.
It's all functional, too, though Audi claims the inspiration for those blistered arches came from its old 90 quattro IMSA GTO, leaving us thinking just how the RS 5 might look in white, with the black, grey and red striped livery that adorned the racer that allegedly inspired it. Fantastic, no doubt. Even in conventional hues it's a head-turner, the added aggression of the RS changes very welcome indeed. There are options to change its appearance further, so the buyer can swap the brushed metal finishes for black, for example.
Inside, it's all familiar Audi A5, and there's absolutely nothing wrong with that. Obviously there's the RS-specific changes like more sporting seats, a chunky, flat-bottomed steering wheel, lots of perforated and contrasting stitched leather - or Alcantara depending on your preference. The standard equipment list also includes things like Audi's Virtual Cockpit with RS-specific displays. There's room in the back for a pair of flexible adults, while the fit, finish and material quality inside are, as we've come to expect from Audi, exceptional. Connectivity is plentiful, and operationally it's all a cinch, the RS 5 no different in that respect to its lesser A5 relations.
The old Audi RS 5 was a frustrating beast; it came with a mighty, fast-beating 4.2-litre V8 heart, which was saddled with a chassis that never quite lived up to the powerplant's magic. In the new RS 5, that's changed. There's a 2.9-litre V6 under the bonnet, turbochargers filling the capacity and cylinder void to generate the same 450hp of the V8, but there's a sizeable leap in torque. That new engine benefits a number of areas, not least economy and a reduction in weight and improved weight distribution thanks to the loss of a pair of cylinders over the front axle. Then there's that torque; the way the RS 5 hauls from low revs is impressive, peak torque arriving at 1,900rpm and hanging around until 5,000rpm, at which point you're a few revs short of peak power.
The result of that is a car that's sensationally quick, almost anywhere in the rev range, aided by the eight-speed automatic transmission that replaces the old seven-speeder. Anoraks will note that new gearbox is a conventional automatic rather than a dual-clutch auto of the old RS 5, though you'll do well to notice from behind the wheel such is the speed of it shifts. You can change gear for yourself, but Audi almost doesn't want you to, as the paddles on the back of the wheel spokes are tiny as ever and feel of poor quality plastic. A bit of aluminium or carbon fibre would do wonders there. The quattro drivetrain has been developed to be quicker acting, the usual split for the drive being 40 per cent front and 60 per cent rear, with more pushed to the back if necessary. Traction is never an issue then, aiding the RS 5's class-leading 3.9-second 0-100km/h time, while the four-wheel-drive assurance makes for wicked cross-country pace.
You'll be doing well to keep up in a Mercedes-AMG C 63 Coupe or BMW M4 then, but for all its knockout pace the RS 5 doesn't quite stir the soul like its rivals. The chassis is undeniably better than its predecessor's, and grip sensational, but at road speeds it's all a little bit too clever and remote, where its rivals are more challenging and enjoyable. The suspension rides with surprising suppleness (tested on optional RS Sport Plus suspension with Dynamic Ride Control) and the steering is nicely weighted and accurate, but it still feels very Audi in its approach, which veers towards effectiveness rather than that more difficult intangible that is driver engagement. Given its status as the range-topping RS-badged model that's a little bit disappointing and, what's more, it makes it difficult to justify spending the not insignificant premium it commands over its conceptually similar Audi S5 relation. Given that comes with a 354hp turbocharged 3.0-litre V6, an eight-speed automatic and quattro four-wheel drive and the sort of performance you'll never find lacking on the road, that's food for thought.
What you get for your money
We can't say yet for the Irish market with any certainty what the RS 5 will cost or come with as standard, but being the range-topping model the equipment list should be fairly comprehensive. If Audi Ireland doesn't do so as standard, then be sure that you specify yours with the RS Sport Suspension Plus, as well as the Sports Differential and Sports Exhaust.
Better in so many ways, the new RS 5 isn't likely to disappoint Audi's current RS customers, but neither is it likely to have AMG or BMW M owners switching teams. A hugely fast, hugely capable car, it's lacking that last final element of excitement and driver appeal that define the best cars in this rarefied class.