Audi has bucked the trend for downsizing engines with its new five-cylinder RS3 Sportback. Instead of moving to a four-cylinder engine for its hottest hatch, the German manufacturer has stuck with the bigger engine, working to reduce the fuel consumption figures and performance over the figures achieved in the outgoing RS3 by cutting the car's weight by over 50 kg (121 lb).
At the heart of Audi's latest hot hatch is an evolution of the brand's turbocharged 2.5-liter, five-cylinder motor. Producing 270 kW (367 hp), the engine is the most powerful in the range of cars produced on Volkswagen's MQB platform and will sprint to 100 km/h (62 mph) in just 4.3 seconds with the help of launch control, outdoing the Mercedes A45 AMG's time by 0.3 of a second. The Audi's engine also makes 465 Nm (343 lb.ft) of torque for responsive in-gear performance.
Powerful though it may be, the new RS3's economy doesn't quite stack up when compared with its closest rival. The Mercedes A45 AMG's turbocharged four-cylinder uses a claimed 6.9 l/100km (34 mpg) and emits 165 g/km of CO2 on the combined New European Drive Cycle (NEDC). By comparison, the new RS3 emits 189 g/km of CO2 and achieves 8.1 l/100km (29 mpg) on its way to an electronically limited top speed of 250 km/h (155 mph).
These figures, although not class-leading, are a 10 percent improvement on those of its predecessor.
If bragging about top speed is your thing, Audi will also remove the limiter for a top speed of 280 km/h (174 mph). The handbuilt engine itself is quite short at just 49 cm (19.3 in) long, and takes advantage of the strength and light weight provided vernicular graphite cast iron for the crankcase. Power from the motor is transmitted through a seven-speed dual-clutch gearbox, which Audi claims causes "no perceptible interruption of power" on full-throttle upshifts.
All-wheel drive is also a key part of the new RS3 package. The car's quattro system is handled by an electronically controlled, hydraulically actuated central clutch that can send between 50 and 100 percent of power to the rear wheels. Audi claims the car has a very "direct" turn in, and will even perform "controlled drifts" before the front wheels pull the car straight as you exit the corner.
That sharp turn in is aided by the RS3's chassis upgrades, which include a wider front track and suspension (McPherson suspension up front, multi-link at the rear) that has been lowered by 25mm (1 in). Audi has also fitted the car with torque vectoring, which will brake the RS3's inside wheels to stop it running wide.
Differentiating the RS3 from tamer, garden-variety A3's is a set of 19-inch five-spoke wheels, which are wrapped in 235/35 tires. Hiding behind these wheels are brakes measuring 370 mm (14.6 in) at the front and 310 mm (12.2) at the rear or, if you tick the right options box, a set of 370 mm front carbon ceramic discs.
The RS3 also has a more aggressive front end, with bigger air intakes than on the standard A3, while twin exhausts at the rear hint at the car's potential.
Audi will begin delivering RS3's in the middle of 2015, with no word yet on pricing.