AUDI’S bestseller has been re-sculptured and refined on the eve of its toughest test.

In charge of aiding its 2005 sales recovery against the Mercedes C-Class and all-new BMW 3 Series, Lexus IS200 and Alfa 159 assault, the B7-series A4 features fresh skin, finer handling, improved ride and upgraded engines.

While much of the platform and cabin are carryovers, the redesigned front and rear-ends mean the sedan and Avant wagon are 38mm and 41mm longer respectively.

Dominating the nose is the company’s signature "single-frame" grille as per the A6 and five-door A3, as well as new peanut-shaped headlights and body-coloured bumpers, bonnet and mudguards.

Two-piece tail-lights mimic the headlights visually, the sedan’s longer boot is 15-litres larger and there are now twin tailpipes.

Three new engines that meet future EU4 lower-emissions standards join the existing base 2.0-litre (96kW/195Nm) and turbocharged 1.8T (120kW/225Nm) twin-cam 20-valve four-cylinder units.

Pinched from the upcoming VW Golf GTi is a 147kW 2.0-litre twin-cam 16-valve four-cylinder turbocharged FSI (Audi-speak for direct petrol injection) motor.

Known as the TFSI, its claimed 0-100km/h time is 7.3 seconds, and can return 8.3L/100km.

Top dog in the new A4 engine line-up is a completely new 188kW/330Nm 3.2-litre FSI V6, available from May in both front and quattro (for Torsen centre differential permanent all-wheel drive) guises.

This one can hit 100km/h from standstill in 6.8 seconds on its way to a speed-restricted 250km/h, while averaging 9.7L/100km.

And a first for the A4 locally is the arrival of a 2.0-litre turbo-diesel four-cylinder engine.

Due around August, this TDI develops the same 103kW and 320Nm here as it does in the Golf and A3, delivers 6.4l/100km and a 0-100km/h time in 9.8 seconds.

Audi is also considering the 3.0-litre TDI V6 that already accounts for up to 25 per cent of all sales of the recently released A6.

On the automatic gearbox front the acclaimed continuously variable transmission (CVT) in front-wheel drive A4s has been improved with a seven-step and sporty ‘S’ facilities, while the revamped Tiptronic in the quattros now have six-speeds that offer a greater and more usable spread of ratios.

Only the 2.0 20V engine retains a five-speed manual. Audi says its new six-speed manual in the turbo petrol units has shorter, smoother throws.

Its compactness also allows for the unit to be mounted further back, improving the A4’s weight distribution for better driving dynamics.

Also to this end, Audi has been listening to the old A4’s critics by addressing the car’s handling while improving ride comfort.

There’s revised suspension, employing the rear trapezoidal links and wheel carriers plus the stiffer track rods from the 253kW S4 sports sedan, while the control arm mounts come from the larger A6.

Servotronic steering, which increases the weight of the tiller as speeds rise, has also been incorporated throughout the range.

Larger and more progressive brakes are standard, as is a full-sized spare wheel on all models.

A new magnesium steering wheel that echoes the grille design is the most obvious change inside, along with new seats (also A6-derived) and revised trim.

New options include bi-Xenon headlights that swivel 15 degrees with the steering for improved night vision, DVD-based satellite-navigation with more intuitive controls and Bluetooth mobile phone connectivity, tyre-pressure monitors and four fresh colours.

In the safety stakes there are new anti-whiplash front-seat head restraints, intelligent front airbags along with rear side airbags, and beefed-up B-pillars that are better able to withstand heavier-vehicle (like SUV) intrusion.

Also new is the latest Electronic Stability Program (ESP 8.0), featuring anti-lock brakes, brake-force distribution, brake assist, traction control, electronic differential lock and a new brake disc wipe for maximum stopping efficiency.

Later this year the revised S4 arrives, while the giant-killing RS4 – with 313kW and 430Nm from its 4.2-litre V8 – should be here early in 2005.

There’s also more standard equipment now, including new-design alloy wheels, the aforementioned active head restraints, rear side airbags, new leather trim and a multi-function steering wheel.

The S-Line package launched last year carries over into the B7, and includes 17-inch alloy wheels, sportier grille/bumpers and aluminium trim accents, and sports seats for the $3600 ask.

That’s not to be confused with the A4 Sport pack which, for your $1800-$2500 depending on the model (2.0 20V, 2.0 TDI, 1.8T, 2.0 TFSI), also adds 17-inch alloys and sports seats, but also boasts sports suspension and a multi-function steering wheel.

Audi is aiming at shifting around 200 A4s monthly for the remainder of 2005. By 2009 it hopes to top 8000 annually, with 55 per cent (or about 4500) made up of the A4.

The buy-back plan that should contribute to about 25 per cent of Audi’s 4500 2005 sales total is now only earmarked for the A6 and A8.

Like before, the 2.0-litre Multitronic is expected to be the best-selling variant.

Roughly speaking, the model breakdown is 40 per cent 2.0, 25 per cent 1.8T, 15 per cent 2.0T FSI and 10 per cent each for 2.0 TDI and 3.2 V6.

Demographically Audi says it is aiming for younger singles or couples with no/young kids, who are managerial or entrepreneurial, technically savvy, design-conscious, tertiary educated and in the $80,000-plus annual income bracket who enjoy driving but are understated in the type of image they project.