Turbocharging and supercharging share top billing in the new Audi A1 1.4 TFSI S line 185PS, which is available to order in the UK from this week priced from £20,705 OTR. The new top-performing A1 derives its impressive performance from a potent combination of the two forced induction methods working sequentially, but nevertheless manages to maintain frugal 47.9mpg economy potential giving CO2 output of just 139g/km.

The compact and lightweight four-valve-per-cylinder ‘dual-charged’ engine powers the A1 1.4 TFSI 185PS from rest to 62mph in just 6.9 seconds, and on to a 141mph top speed. Under power, the supercharger is the first to exert its influence, intervening at around 1,500rpm to increase thrust. In most cases it then disengages at around 2,400rpm, to be followed from around 3,500rpm by a boost from the turbocharger to hasten progress yet again.

As the supercharger takes care of low-range boost, it has been possible to use a larger turbocharger designed with optimum efficiency in mind, and this is reflected in the impressively strong combined cycle fuel economy and low emissions.

The S tronic seven-speed twin-clutch transmission directs power to the front wheels as standard, and with its ability to perform gear shifts in just a few hundredths of a second perfectly suits the newcomer’s temperament. Its tall seventh gear also reduces fuel consumption.

ESP with limited slip differential

McPherson strut front and torsion-beam rear suspension with separate springs and dampers and taut S line settings forms the basis for agile handling, giving keen turn in and impressive mid-corner stability and grip. Control under pressure is also safeguarded by the latest ESP stabilization program with electronic axle differential lock, which initiates very brief braking of the inside front wheel when its sensors detect an impending loss of traction during fast cornering.

The performance-oriented S line suspension forms part of the overall S line specification that is standard for the 1.4 TFSI 185PS, and includes features such as an exclusive S line exterior treatment, 17-inch alloy wheels and part leather-upholstered sports seats. This is in addition to the Sport equipment level which already includes remote central locking, air conditioning, electric front windows and mirrors, Bluetooth mobile phone preparation, Driver’s Information System and a six-speaker single CD audio system with auxiliary iPod connection linked to a 6.5-inch retractable display.