As Audi has already bid a fond farewell to both the TT and the R8, now it is sending the mighty RS 6 Avant off into the mists of time with a valedictory hurrah, and it's called the RS 6 GT.
Runs 630hp iteration of 4.0-litre V8
The GT is based on the RS 6 performance, the 630hp evolution of the 'regular' C8 RS 6, so that means uplifts of 30hp and 50Nm (850Nm peak) for Audi's familiar 4.0-litre biturbo V8. This cuts the 0-100km/h time from 3.6 to 3.3 seconds (and that's a tenth quicker than the performance model, too, for reasons we'll soon come onto), while the GT's top speed of 305km/h is higher than the standard RS 6's 280km/h (limited) figure.
It's not so much the speed which defines the RS 6 GT, however, but the focus of its performance. This is designed to be the most rewarding RS 6 to drive yet, which is quite some accolade, given the brilliance of the 600hp version and the undoubted improvements to that car the RS 6 performance model brings. The key thing to note here is a programme of weight loss, albeit one that is incremental rather than dramatic, but let's start with the car's appearance first.
The GT takes its inspiration from the RS 6 GTO concept car of 2020, which - in turn - was informed by the glorious Audi 90 quattro IMSA GTO racer of 1989. This wide, box-arched, saloon is obviously referenced in the look of the RS 6 GT. However, despite appearances, the GT is not any wider than any other RS 6.
Instead, clever visual tricks improve the stance of the GT - such as its front 'Singleframe' grille and air intakes all being finished in high-gloss black, as well as the inclusion of vertical blades in the front apron, the new air outlets behind the front wheels (to reduce pressure in the wheel arches and simultaneously improve brake cooling), and a change to the base of the tailgate to visually lower the loading lip of the car and make it look broader. This last touch is assisted by a massive aerodynamic diffuser under the rear bumper that has more vertical vanes and a centrally mounted, upright reflector.
No roof rack for you
Perhaps the neatest visual flourish of the GT is that it is the first RS 6 Avant without roof rails. The deletion of these subtly gives the car a much sleeker, lower and sportier appearance.
There are obviously other design features which relate to the pinnacle status of the GT in the RS 6 line, as well as others that revolve around the weight-saving goals. So a deeper, more menacing front splitter is incorporated into the front bumper, while around the sides are enhanced side skirts with an insert, glossy carbon door mirror caps and gorgeous six-spoke 22-inch wheels - clothed in Continental SportContact 7 tyres for greater wet/dry grip and reduced high-speed understeer - which are forged and lighter than the standard alloys. Then, at the back and perching atop the RS 6 GT Avant's roof, is an impressive double-deck, 'pass-through' spoiler.
Carbon front end an Audi first
What you can't immediately spot is that the bespoke front wings and the bonnet of the RS 6 GT are all made of carbon fibre - with the use of the material for these panels marking the first time any production Audi has received such items. The bonnet is painted on the outside, and it takes a lot of effort and coats to make it look like it is metal - but if you pop it and lift it, then the carbon-fibre underside is exposed in its natural weave. Coupled with the wheels and one of the key interior changes, which we shall come onto, the carbon front end helps to shave 15kg from the kerb weight of an RS 6 performance (or 25kg from the 600hp model) resulting in the GT's overall 2,075kg figure.
Aside from these alterations, the only other things to note on the outside of the car are both discreet, in the form of the unique badging - including a 'GT' legend on the trailing edge of the front wings and an exclusive black boot logo with an Audi Sport graphic - and then... not so discreet. You can't fail to have noticed the graphics on the car in the pictures: this is one of two 'wraps' that can be chosen with three of the five available body colours for the RS 6 GT.
So, the basic paints are Arkona White, Nardo Grey, Chronos Grey metallic, Madeira Brown metallic and then Mythos Black metallic. The wrap graphics are only available with Arkona, Nardo and Mythos - choose the white, as seen here, and the 22-inch wheels are painted in the same colour, while the black, grey and red livery is a direct nod to that IMSA GTO and the RS 6 GTO concept. On Nardo and Mythos cars, the look is toned down somewhat with the decals switching to black and grey, while the wheels are either high-gloss or matte black.
Interior features exclusive touches
Inside, the RS 6 GT gains the RS Design Package as standard, which is then enhanced with various model-specific touches. This means there is a lot of Dinamica microfibre within, as well as exclusively coloured stitching for the GT in red and copper. The floor mats gain 'RS 6 GT' emblems, as do the exquisite RS bucket seats - carbon-backed, these items are not only incredibly pleasing to the eye and hugely supportive to sit in, but they contribute to the car's lower weight too. Decorative inlays are finished in black microfibre as standard, or open-pore carbon twill as an option.
Final flourishes in the GT's cabin are seatbelts in Crimson Red, while the centre console bears each car's individual number in the limited built run of 660 units worldwide.
Hardcore chassis set-up guaranteed
To help the RS 6 GT make the most of its lower weight and more powerful engine, the standard drivetrain spec - of quattro all-wheel drive and an eight-speed Tiptronic transmission - has been enhanced, thanks to the rear-axle-mounted quattro sport differential having its own state of tune specific to the GT to promote more tail-happy driving characteristics; the car also has the latest locking centre differential seen on the RS 6 performance, which favours a 40:60 front-to-rear torque split most of the time, with maximums of 70 per cent front and 85 per cent rear torque possible.
For a two-tonne-plus estate that can run 0-200km/h in 11.5 seconds - that's 1.5 seconds quicker than a 600hp RS 6 can manage it - stopping power is equally important, so the GT has the RS ceramic braking system as standard.
The biggie in the chassis, though, is that the GT gains coilover suspension with three-way adjustable dampers. This system is relatively light and also requires adjustment via the suspension turrets' top mounts, rather than by doing it in-car from a button, and while it's the first time such a dynamically focused set-up has been seen on the RS 6, both the RS 4 and RS 5 have been offered with 'competition' packages which included this technology and the rear-biased sport diff - and the competition kit really transformed those cars, so we're hoping for similar handling gains for the mighty RS 6 GT.
With a 10mm-lower ride height than a regular RS 6, higher spring rates and stiffer anti-roll bars (30 per cent front, 80 per cent rear), the GT could be quite an intense machine for many people - hence why Audi will offer it with the option of two less focused suspension options, which are RS Sport suspension with Dynamic Ride Control, or full RS Adaptive Air suspension.
Hand-finished at Böllinger Höfe
The final difference of the GT is that, unlike other RS 6 models, it is not entirely assembled on the main production line in Neckarsulm in Germany. Instead, it goes off to the net-carbon-neutral facility at nearby Böllinger Höfe - where both the R8 supercar and e-tron GT electric vehicle are produced - to be hand-finished by seven specially trained employees. Here, all the GT-specific features, such as the bonnet, the wings, the rear wing, the front and rear bumpers and the adjustable coilover suspension, are fitted, with each car spending an entire day there for the process to take place.
As mentioned earlier, the Audi RS 6 GT Avant is only being produced in a run of 660 vehicles for the entire world. There's not much chance any will officially come to Ireland - we don't even get the performance variant on the price list, never mind the GT - but there is a right-hand-drive allocation for the UK, which means importing one of these dream machines here might not be beyond the realms of all possibility... but be prepared to pay handsomely for the privilege. Rumours are the GT will cost around 60 per cent more than a regular RS 6, which - going on our basic list price of €184,665 - would mean somewhere north of €295,000 if you can get hold of one...