The front-wheel-drive Audi A1 is the sportiest car in the premium subcompact class. It is nimble and agile in the city, steady and precise on interurban roads, and comfortable on the highway. These qualities can be attributed largely to the sophisticated chassis with the favorable weight distribution.
The engineers devoted a great deal of attention to the distribution of axle loads during the development of the Audi A1. Only 808 millimeters (2.65 ft) long, the front overhang is unusually short. Depending on the engine, only between 61 and 63 percent of the weight is on the front axle. A number of different details contribute to this, such as the battery, which with most engine options is located beneath the luggage compartment. With a base weight of only 1,040 kilograms (2,293 lb), the A1 is the lightest vehicle in the premium compact class.
The front suspension is a classic McPherson design with lower wishbones and new elastokinematics. The subframe is made of high-strength steel. A torsion beam axle with the springs and dampers separated is used in the rear. Newly designed guide bearings were used to optimize the elastokinematics for driving dynamics and comfort. The A1 has an usually wide track, measuring 1,477 millimeters (4.85 ft) up front and 1,471 (4.83 ft) at the back.
Precise and efficient: the power steering
The youngest Audi comes equipped with electrohydraulic, rack-and-pinion power steering. The flow of oil is produced by an electric motor, which works more efficiently than a strictly hydraulic system. As speed increases, the speed of the electric motor and thus the power assist decrease. The volumetric flow increases with high steering angles.
Steering response is spontaneous; feedback is precise and sensitive. The steering ratio is a very direct 14.8:1. The high turn-in of the front wheels keeps the turning circle to 10.6 meters (34.78 feet) – both factors make the A1 extremely agile.
Audi has tuned all chassis components for sportily balanced handling. The front control arm bearings, for example, are stiff to improve lateral support. The rear bearings, on the other hand, have non-linear characteristics for better comfort.
Twin-tube gas shock absorbers with supplemental polyurethane springs provide the damping at all four wheels. A tautly tuned sport suspension is standard with the Ambition trim line, optional with Attraction. quattro GmbH also offers a special S line sport suspension.
Dynamic and safe: ESP with electronic limited slip differential
The A1 comes equipped with an attractive Audi technology regardless of the engine selected – the ESP stabilization system with electronic limited slip differential. Similar to an mechanical locking differential, it makes the already agile handling even more dynamic. If the controller detects that the load on the inside front wheel is reduced too much, it initiates brief, controlled braking of that wheel – not more than subtly touching the pads to the disc with minimal pressure.
The smooth and continuous intervention takes place before excess slip, which would waste significantly more energy, can occur. The slight braking causes the excess torque to flow to the outside wheel, which can apply more power to the road. At the same time, the difference between the drive forces generates a certain yaw moment that helps the driver by turning the car very slightly into the corner.
The result is impressive whichever way you look at it: The A1 remains neutral noticeably longer, and understeer is largely neutralized when turning into corners and when accelerating. The ESP stabilization program intervenes later and more gently, if it is even necessary at all. Overall road behavior is even more precise, agile, stable, further enhancing objective safety and the driver’s subjective confidence in the car.
Sporty: the wheels and brakes
The ESP in the A1 controls large, powerful brakes. The front discs are internally ventilated and have a diameter of 256 millimeters (10.08 in) on the 1.2 TFSI and the 1.6 TDI with 66 kW (90 hp); on the more powerful models they have a diameter of 288 millimeters (11.34 in). All models sport solid, 230 millimeter (9.06 in) discs gripped by aluminum floating calipers in the rear. The brake lights blink during emergency braking to warn trailing traffic. The warning blinker is also activated when the car is at rest.
The Attraction trim line features 15-inch steel wheels, with aluminum wheels available as an option. Models with the base engines roll on 185/60-series tires that have been designed specifically for good aerodynamics and low rolling resistance. More powerful models step up to 205/55. The A1 Ambition comes standard with 16-inch alloy wheels in two designs and shod with 215/45-series tires. Run-flat tires are optional. A number of optional 16-inch wheels are also available.
Audi also offers the option of elegant 17-inch and 18-inch cast aluminum flow-formed wheels. These can be partly polished or may have colored decorative elements, if desired, and are shod with sporty 215/40-series wide-format tires. quattro GmbH offers 18-inch wheels and wide-format 225/35-series tires in conjunction with the S line sport suspension. 15-inch and 16-inch winter wheels round out the program. A tire mobility system under the cargo floor of the A1 is standard. An optional tire pressure monitoring system is also available.
The equipment and data specified in this document refer to the model range offered in Germany. Subject to change without notice; errors and omissions excepted.