The new five-pot mill generates 294kW of power, as well as 480Nm of torque between 1700 and 5850rpm. Drive is delivered to all four wheels via a seven-speed dual-clutch transmission.
That's good enough to catapult the new RS3 sedan from 0-100km/h in 4.1 seconds, and onwards to an electronically limited top speed of 250km/h, although this can be upped to 280km/h on request.
By way of comparison, the RS3 Sportback has a 270kW/465Nm 2.5-litre turbocharged engine, and completes the 0-100km/h standard in 4.3 seconds.
The distinctive burble of the five-cylinder engine can be modulated and tuned by the Audi Drive Select system, which also includes three modes (comfort, auto and dynamic) for the car's steering, transmission, engine management and handling setups.
Compared to the regular A3 sedan, the RS3 sits 25mm closer to the ground. The RS3 also has flared wheel arches to accommodate the vehicle's 20mm wider front track, and 14mm wider rear track.
Other exterior visual changes include new front and rear fascias, a boot lid lip spoiler, rear diffuser, and large oval exhaust tips.
Standard features include a 7.0-inch infotainment screen, illuminated door sills, plenty of RS badging inside and out, and black Nappa leather seats.
The RS3 rides on standard 19-inch wheels fitted with 235/35 tyres. Braking power is provided by 370mm discs up front with eight-piston callipers, and 310mm discs at the rear. Carbon-fibre ceramic discs and larger tyres are present on the options list.
Other available options include Qi inductive smartphone charging, a 14-speaker 705W Bang & Olufsen sound system, sports bucket seats, and the company's 12.3-inch Virtual Cockpit instrumentation system.
Update: Audi Australia has confirmed that the RS3 will go on sale in the Australia from around the middle of 2017.