Audi is priming a track-focused special edition of the RS3 as it celebrates the hot hatch’s signature five-cylinder engine, with the unit under threat from forthcoming EU emissions regulations.

The new variant has been spotted testing on the Nürburgring Nordschleife for the first time ahead of its launch, expected to take place early next year.

It sports several racing-inspired modifications, including a more aggressive front splitter, new canards and a chunkier rear spoiler, intended to maximise its pace on circuit. 

The RS3 prototype also wears a new set of brake calipers, painted blue rather than the standard black, hinting at extra stopping power and the potential of a special colour scheme or livery.

The new car is also likely to bring a significant uplift in power and torque from the 401bhp and 369lb ft of the previous RS3 Performance Edition, the punchiest version of the hot hatch yet offered. 

Sebastian Grams, former managing director of Audi Sport, told Autocar in 2023 that “there's still a way to go” with the five-cylinder engine compared with the RS3 Performance Edition.

Dutch sports car maker Donkervoort previously boosted the 2.5-litre turbocharged unit to 493bhp for its F22 open-wheeler.

It remains to be seen whether Audi will push it that far, but a tangible improvement in output could make the RS3 the most powerful petrol hot hatch on sale, outdoing the 416bhp Mercedes-AMG A45 S.

It's likely that the new RS3 variant will represent one last hurrah for the car and its engine, in similar fashion to 2022’s Audi TT RS Iconic Edition.

The five-cylinder unit has been the RS3’s unique selling point since its arrival in 2011, but Audi previously said the powerplant's production would end when the current iteration of the hot hatch comes off sale.

It is possible that it could be reworked to meet the rules, be it through redevelopment or by way of electrification, however.