What is it?
The fastest and most engaging Audi S4 yet. The old 4.2-litre V8 petrol engine is gone, with a supercharged 3.0-litre V6 in its place. The new powerplant is 20kg lighter and a good deal more compact.
This has allowed Audi to mount it further back in the engine bay for a 60:40 front-to-rear weight distribution, most of the mass now residing behind the front axle line for greater balance.
Running a mechanical supercharger, the four-valve-per-cylinder unit kicks out 328bhp between 5500 and 7000rpm - down by some 11bhp on the outgoing S4. But the new engine delivers 22lb ft more torque than before, releasing an impressive 324lb ft being between 2900 and 5300rpm.
These reserves are channelled to all four wheels via a standard six-speed manual gearbox. A rapid-fire seven-speed DSG is available as an option.
Audi claims 0-62mph in 5.1sec for an S4 with the double-clutch ‘box – some 0.8sec inside the official time of the old S4. A more telling indicator of its performance is its 50-75mph fourth gear time of just 4.4sec. Even in sixth gear, it only needs 7.1sec between the two marks. Top speed continues to be limited to 155mph.
What is even more impressive is that the S4’s new supercharged 3.0-litre V6 achieves all this with a 27 per cent decrease in consumption over the old naturally aspirated 4.2-litre V8 with a combined cycle average of 29.1mpg.
What’s it like?
The smaller engine has robbed the S4 of some of its more memorable acoustic qualities, but this new model is quicker off the line, urgent through the gears, extremely agile for a car weighing 1650kg, progressive when you get towards the limit of adhesion and extremely stable at high speed.
We tested the double clutch gearbox and found that it encourages spirited driving. Its tightly stacked ratios help to make the most of the prodigious low-end torque and flexible qualities of the engine.
Upshifts are crisp and smooth even at high revs, while the electronics are clever enough to provide an alluring blip on the throttle on the downshifts.
The best thing about the S4, however, is its heightened dynamic ability. There is an inherent sharpness to its actions that make it a much more engaging car to drive than its predecessor. It all starts with the steering, which is both direct and terrifically well weighted. This is backed up by excellent body control and seemingly endless levels of grip.
The new Audi S4 is also the first model from Ingolstadt to receive what Audi describes as its sport differential. This is a complex torque vectoring gear set that acts very much like a traditional mechanical locking differential by varying the amount of drive going to each rear wheel. All of which results in a much more stable feel during cornering and higher apex speeds.
Another area where the new S4 displays a clear advance on the model it replaces is in the quality of its ride. With the addition of electronic dampers for the first time, it gives the driver the choice between three different levels of stiffness – comfort, automatic and dynamic.
Buyers can also option their car up with Audi’s so-called ‘drive select system’, which provides the basis for sharper and more responsive actions by remapping the characteristics of the throttle, transmission shift points, dampers and steering – the latter receiving a low friction axial transmission that provides a wonderfully direct feel.