New Audi S4 - First Drive

A new engine, more power than ever before and a host of technological advancements are just some of the new Audi S4’s arsenal of impressive weaponry.

Due to arrive in Australia towards the end of the year, this new model will employ turbo power instead of the supercharged powerplant used in the outgoing model, resulting in the most powerful Audi S4 ever produced.

Under the skin

The coming S4’s 3.0 V6 is effectively a new engine. Although it shares its cylinder bore and piston stroke with the supercharged engine it replaces, the two are not closely related though their capacities are identical.

According to Audi drivetrain development engineer Johannes Ohland, there are around 800 all-new parts in the turbocharged V6. The engine’s cylinder block, its core, is one of them. There’s a little more distance – 3mm – between the cylinder bore centres of the new engine, says Ohland.

That huge number of new parts is mostly a result of the decision to adopt what Audi engineers call a ‘hot side inside’ layout. This means the space on top of the engine, between the 90-degree ‘vee’ created by its two rows of three cylinders, is where the exhaust system, including a sophisticated twin-scroll turbo, is to be found. Normally turbochargers are located outside the ‘vee'.

It’s unusual to see this layout in a V6, but Audi already uses it in the twin-turbo 4.0-litre V8 engine. The big benefit is a short journey for the scaldingly-hot exhaust gas from combustion chamber to the turbocharger, and that means quicker response when the accelerator is pressed.

The changes needed to make the engine work this way are major. All new cylinder heads, and intake and exhaust systems are required. But the results are worth the four years of work Audi engineers invested in developing the engine.

With 260kW, the turbo 3.0-litre V6 is the most powerful engine ever installed in an S4. As well as an extra 15kW compared to the outgoing supercharged V6, the new engine has more torque, spread across an incredibly wide range of revs. The 500Nm maximum is available all the way from 1370 to 4500rpm.

As a result the new S4 is quicker. Audi claims a 0-100km/h time for the sedan version preferred by most Australian customers of just 4.7 seconds, an improvement of 0.3 seconds. And the slightly larger Avant wagon slips below the 5.0 seconds for the 0-100km/h performance benchmark for the first time. At the same time, fuel consumption is down by five percent.

The engine shouldn’t be given all the credit for these achievements. Audi reduced the overall weight of the latest ninth-generation of the A4, and the S4 is also lighter than the model it will replace. The new S4 also gains an extra, economy enhancing gear ratio. Instead of the seven-speed double-clutch S tronic of the previous S4, the new model uses an eight-speed tiptronic with torque convertor.

On the road

The new turbo 3.0-litre V6 is a thriller to drive. The solid wave of thrust, even from low engine speeds, is truly wow-worthy. There’s a nice rasp from the exhaust around 2500 to 3000rpm, but the engine is at its vocal best with the standard Audi drive select set to Dynamic.

As well as opening valves in the S4’s mufflers that increase the V6’s high-rev bark, dynamic mode also adds some bite to throttle response. As well as engine, the sportiest of drive select’s five modes also affects the transmission, drivetrain, steering, dampers and, if fitted, rear sport differential.

Dynamic makes the most of the S4’s firmed and lowered suspension, and the inbuilt bias of its quattro permanent all-wheel-drive system. Its centre differential is set up to normally send 60 percent of engine torque to the rear axle. On the 19-inch wheels and tyres that will be standard specification in Australia, the S4 has truly remarkable grip, especially when powering out of corners. It’s also surefooted while using its enlarged brakes to slow at the same time as turning into a corner. 

The auto and comfort modes calm the S4 considerably showing its more sedate side. Reactions to the accelerator are more measured, the ride more pliant and the exhaust quieter. For commuting, or when comfort is the priority, these are the modes to choose.

The interior of the S4 is pleasing for the same reasons as any latest-generation A4; precise and user-friendly design, high-grade materials, excellent infotainment tech and driver-aid systems and, of course, spaciousness. Sports front seats, aluminium pedals and S4 badging are among the touches specific to the sporty sedan and Avant version.

Although the final details for Australia are yet to be decided, Audi is aiming for prices similar to the outgoing S4 sedan and Avant, with an impressive standard equipment list.

The understated exterior of the new S4 means only those in the know will recognise this athletic Audi for what it is. It’s clearly not for blowhard boasters who want a car to match their personality. But those who can sense technical know-how at work and know craftsmanship when they see it will find the subtle and sophisticated new S4 superbly seductive – and with more ’S’ factor than ever.