Following somewhat later is the 1.2 TFSI, which with its aluminum crankcase is rigorously designed for low weight and minimal friction. It produces 77 kW (105 hp) and 175 Nm (129.07 lb-ft) of torque. Together with S tronic, it accelerates the A3 Sportback from zero to 100 km/h (62.14 mph) in 10.7 seconds and reaches a top speed of 193 km/h (119.92 mph). Average fuel consumption is just 4.9 liters per 100 km (48.00 US mpg), corresponding to CO2 emissions of 114 grams per km (183.47 g/mile).

The new 1.4 TFSI in the A3 Sportback, which now also features an aluminum block, weighs just 107 kilograms (235.89 lb) – 21 kilograms (46.30 lb) less than its predecessor. It produces 90 kW (122 hp) and 200 Nm (147.51 lb-ft) of torque, accelerating the A3 Sportback from zero to 100 km/h (62.14 mph) in 9.3 seconds on its way to a top speed of 203 km/h (149.73 mph). Its average fuel consumption is 5.3 liters of fuel per 100 km (44.38 US mpg), which corresponds to 123 grams of CO2/km (197.95 g/mile).

A second version of the 1.4 TFSI to follow somewhat later produces 103 kW (140 hp) and 250 Nm (184.39 lb-ft) of torque. It features the innovative cylinder on demand (COD) system, which deactivates the second and third cylinders at low to intermediate loads and while coasting.

The powerful 1.4-liter engine’s average fuel consumption is thus 4.7 liters of fuel per 100 km (50.05 US mpg); CO2 emissions are just 110 grams per km (177.03 g/mile). Performance is sporty, with a time of 8.4 seconds for the standard sprint (with manual transmission) and a top speed of 213 km/h (132.35 mph).

The new 1.8 TFSI, the most powerful gasoline engine in the lineup, produces 132 kW (180 hp) and 250 Nm (184.39 lb-ft) of torque. It combines FSI direct injection with indirect injection and uses the Audi valvelift system to vary valve lift as required. The exhaust manifold is integrated into the cylinder head – a similar solution is also used in the two smaller TFSI engines. Key performance data with S tronic and front-wheel drive: from zero to 100 km/h (62.14 mph) in 7.3 seconds, top speed of 232 km/h (144.16 mph) and average fuel consumption of 5.6 liters per 100 km (42.00 US mpg) corresponding to 130 grams CO2 per km (209.21 g/mile).

Audi will quickly expand the range of engines for the A3 Sportback. It includes a dynamic S model and additional high-efficiency, low-emissions variants. Set to debut in 2013 is an 81-kW (110-hp) TCNG engine for operation with Audi e-gas, a fuel that Audi produces itself in sustainable manner. In the holistic well-to-wheel analysis, the CO2 emissions of the A3 Sportback TCNG are below 30 g/km (48.28 g/mile). The A3 Sportback e-tron with a powerful plug-in hybrid drive will follow in 2014.

Power transmission.
All engines in the new Audi A3 Sportback are paired with a manual six-speed transmission. S tronic is available as an option with all engines. Depending on the version, the dual-clutch transmission shifts extremely quickly and nearly imperceptibly through six or seven gears.

The driver can operate S tronic via the selector lever or with the optional paddles on the steering wheel. Revs are somewhat higher in the automatic S mode, whereas D mode prioritizes taller gear ratios. When combined with Audi drive select (standard in the A3 Ambition), S tronic includes a free-wheeling function in efficiency mode that further reduces fuel consumption.

With engines producing up to 103 kW (140 hp), the power is delivered to the front wheels. quattro permanent all-wheel drive featuring a newly developed multi-plate clutch is available as an option for the 1.8 TFSI and 2.0 TDI.

The hydraulically actuated and electronically controlled component, which can send the power from the front to the rear axle in just a few milliseconds, weighs significantly less than the previous unit.

Chassis.
The chassis of the new Audi A3 Sportback is balanced, harmonious and sporty thanks to the finely balanced distribution of axle loads. The front axle has been shifted forward by 40 millimeters (1.57 in) compared with the previous model, shortening the overhang correspondingly. All of the engines are installed tilted backward by 12 degrees with the exhaust end facing the bulkhead. This concept is an element of the modular transverse platform (MQB).

The front axle of the Audi A3 Sportback is a McPherson construction with wishbones and lightweight aluminum pivot bearings. It is mounted on an aluminum subframe. Mounted on a steel subframe, the four-link rear suspension handles longitudinal and transverse forces independently. The springs and dampers are mounted separately. The two sport suspensions available lower the body by 15 or 25 millimeters (0.59 or 0.98 in), respectively.

The electromechanical power steering with a direct steering ratio of 15.3:1 is sensitive and highly efficient. Its drive unit consumes no energy while driving straight ahead – a key contribution to overall efficiency. The steering works closely together with a variety of assistance systems, including Audi active lane assist and the parking assistant. The turning circle measures just 10.9 meters (35.76 ft).
Depending on the trim line, the new Audi A3 Sportback rolls on 16 or 17-inch wheels, with attractively designed wheels up to 18 inches in diameter available as options.