Audi thought it best to modify the turbocharged 1984cc four-cylinder TFSi motor. Some piece of work it is, too. Thanks to stronger pistons, beefier conrods, all-new bearings and a strengthened cylinder block, the bottom end is virtually brand new.
On top of this, the cylinder head has been redesigned (compared with the Golf GTi's), including a revised intake system, and both the turbocharger and intercooler are bigger, allowing a maximum boost pressure of 1.2bar. That’s unusually high for a regular production car, and a good indication of how serious a performance car the S3 really is.
The result is 261bhp at 6000rpm with a rev limiter just this side of 7000rpm, plus a flat torque curve between 2500-5000rpm with a peak figure of 258lb ft.
Power is fed to all four wheels, and the Haldex four-wheel-drive system has been uprated to cope with the extra grunt. The clutch is at the rear to optimise weight distribution, and the shift of the six-speed gearbox has been shortened.
Perhaps of even greater significance are the modifications to the S3’s chassis. Not only are the springs stiffer and the dampers of a higher specification than in any other A3, but the ride height has been lowered by 25mm, too.
The S3 also uses aluminium wishbones and pivot bearings in an attempt to reduce unsprung weight. Bigger brakes now nestle menacingly behind the standard 18-inch wheels. The tyres are 225/40 ZR 18s Continental Sport Contact 2s.
Visually you can pick out an S3 from lesser A3s by its silver door mirrors, bespoke wheels and bigger front splitter and skirts. Inside there are ‘S’ logos on the steering wheel and gearknob, as well as chunky sports seats. You can also blow £1685 by specifying the competition-style seats from the RS4.
The overall effect – to look at – is not exactly ground-breaking. For us it’s almost too subtle. At a glance you could easily mistake it for an A3 wearing a few Sportline options.