Shifting into a higher gear in Audi A4 and A5 models could take as little as 0.2 seconds from this month as the latest performance-oriented S tronic twin-clutch automatic transmission makes the transition to 2.0 TFSI quattro versions of the acclaimed compact Saloon, Avant and Coupe. The new S tronic option adds £1,420 to the prices of A4 2.0 TFSI quattro and A5 2.0 TFSI quattro models, taking them to £27,170 OTR and £31,065 respectively.

Despite its rapidity, the latest incarnation of the twin-clutch gearbox also acts responsibly, maintaining fuel economy and CO2 output at the same level, or below, manual equivalents.

Launched to critical acclaim in the first generation TT, the advanced transmission added a new string to its bow during 2008 when it was further upgraded to enable installation in Audi models with longitudinal, ‘North-South' engine installations. The new addition made its debut in the Q5 SUV, and soon after in the latest supercharged S4 Saloon and Avant.

Linked to an all-new engine

It now brings its lightning fast changes to the A4 2.0 TFSI quattro with its brand new turbo charged and directly injected FSI engine enhanced by Audi valvelift technology for improved engine ‘breathing'. In Saloon form, the A4 2.0 TFSI quattro S tronic can power to 62mph from rest in 6.5 seconds - a 0.1 second improvement over the manual version - reach a top speed of 150mph and return 38.2mpg according to the combined cycle test. In the A5 2.0 TFSI quattro S tronic, the sprint to 62mph can be completed 0.3 seconds more quickly than in the manual at 6.2 seconds, and a top speed of 150mph can be reached, while combined economy and CO2 output match the A4 at 38.2mpg and 172g/km.

These impressive economy figures are identical to manual A4 and A5 equivalents, and in terms of CO2 output the A5 S tronic actually shows a reduction versus the manual version's 173g/km, highlighting the fact  that in contrast to most automatic transmissions S tronic demands no compromise in return for added convenience.

Audi A4 S line

Advanced electro-hydraulic controls and the alternate use of two clutches enable the S tronic gearbox to deliver lightning fast automatic or manual shifts via the gear lever or steering wheel-mounted paddle controls with no interruption of the engine's power delivery across seven ratios.

The first of the two clutches serves the odd-numbered gears and reverse, and the second the even-numbered gears, so when the A4 or A5 are travelling in third gear, for instance, fourth is already pre-selected in anticipation. As soon as the shift command is given, the first clutch is disengaged and the second engaged in just a few hundredths of a second, virtually seamlessly.

The sporting credentials of both A4 and A5 2.0 TFSI quattro models can not only be enhanced by the new S tronic transmission, but also by the extra cost option of the Audi drive select adaptive dynamics system. With its influence over throttle response, transmission points, steering weighting and damper control Audi drive select delivers the sharpest possible response and the highest degree of poise in all situations.

New Executive SE and Executive S line models In A4 models it is also now possible to further enhance appeal through highly cost effective specification upgrades following the introduction of new Executive SE and Executive S line trim lines. In addition to the SE equipment list, which among its highlights features 17-inch 7-arm alloy wheels, three-zone climate control, an Audi Concert CD audio system and automatic headlight and wiper operation, Executive SE specification brings an upgrade to 17-inch 10-spoke alloy wheels, an Audi Symphony audio system with six CD autochanger, cruise control and mobile phone preparation. The Executive SE trim line carries a premium of £635 over the SE model, representing a saving of £480 compared with the cost of adding each item individually.

The more sporting S line option that is available at extra cost for all A4 Saloon and Avant models includes 18-inch alloy wheels, a unique S line front and rear bumper design, extended side skirts, xenon headlights flanked by distinctive LED daytime running lights and S line sports suspension lowered by 20mm. Inside, it adds leather and cloth combination sports seats, a 3-spoke S line sports steering wheel, matt brushed aluminium inlays and a perforated leather gear knob.

S line models can also be given the Executive treatment – the Executive S line models that are new for 2009 upgrade to Alcantara and leather combination sports seats, the Symphony audio system with CD changer, cruise control and mobile phone preparation. At £635, the Executive S line premium saves £650 over the cost of the individual items.