The New Audi S4 Cabriolet: In Depth

A powerful, attractive-sounding eight-cylinder engine generating 253 kW (344 bhp) and 410 Newton-metres, the latest generation of quattro permanent four-wheel drive and a design that creates an air of restrained dynamism: these are the hallmark characteristics of the new Audi S4 Cabriolet. The open-top four-seater crosses the genes of an open sports car with those of an elegant cruiser – a car that offers fascination for all the senses.

The front end, with the single-frame radiator grille, is visible evidence of the new generation of the S4 Cabriolet. Like the S4 saloon, the Cabriolet features the S-specific grid pattern and the redesigned standard xenon headlights.

The bumpers with large air inlets, the aluminium-look casings for the exterior mirrors, the redesigned rear lights and the four oval tailpipes are the distinguishing visual features of the S4 Cabriolet. The Audi S4 Cabriolet is fitted with 18-inch cast aluminium wheels of S design with 235/40 R1 8 tyres.

Inside, too, the S4 Cabriolet differs in appearance from its brothers. The instrument cluster has the grey dials that are characteristic of S models and special needles.

The electrically adjustable sports seats with a combined leather/Alcantara upholstery are outstandingly comfortable even over long distances. The seats come with an adjustable thigh support and electrically adjustable lumbar support as standard. The new generation of steering wheels now also features in the Audi S4 Cabriolet, with the impact absorber echoing the design of the single-frame radiator grille.

The V8 engine: compact dimensions, beefy power

The Audi S4 Cabriolet is propelled by a 253 kW (344 bhp) eight-cylinder engine. Its maximum power output is in the region of 7,000 rpm. The 4.2-litre engine delivers a hefty 410 Newton-metres of torque to the crankshaft at an engine speed of 3,500 rpm. Thanks to such a superior power flow from the substantial displacement, this naturally aspirated engine acquires an air of supreme confidence.

Its spontaneous response to every movement of the accelerator and its astonishingly free-revving nature are impressive. The deep, sporty sound of the exhaust system is very immediate, but never over-assertive.

The Audi S4 Cabriolet sprints from 0 to 100 km/h in only 5.9 seconds, and reaches a top speed of 250 km/h, at which point the governor cuts in smoothly.

Surprisingly, the overall length of the eight-cylinder engine is incomparably short at just 464 millimetres. Audi’s engine developers achieved this compactness by means of a chain drive for the camshafts and auxiliaries. The weight is also extremely low for an engine with eight cylinders, at only 195 kilograms. This has definite advantages in terms of the car’s weight distribution and road dynamics.

The engine power passes via a precision-shift 6-speed gearbox. The selector mechanism is decoupled, largely preventing vibrations and load-reversal movements from being transmitted to the gear lever.

The optional extra of 6-speed tiptronic with Dynamic Shift Program, an additional Sport program and shift paddles on the steering wheel unites sportiness with the convenience of an automatic transmission. Whether relaxed cruising or open-top driving, the Audi S4 Cabriolet permits both.

The sports suspension: light and agile

The lightweight aluminium suspension consists of four-link front and trapezoidal-link rear suspension, and is designed to ensure maximum steering precision and clearly defined road behaviour with excellent lateral stability. A low unsprung mass produces a particularly sensitive response from the suspension.

Like the S4 saloon and the Avant, the S4 Cabriolet features firm sports suspension. This provides the ideal basis for maximum agility and, consequently, sheer driving pleasure.

The standard servotronic steering always strikes a good balance between steering precision and lightness, at whatever the speed.

quattro drive: driving fun and ample traction

Thanks to quattro, the Audi S4 Cabriolet can translate engine power into optimal progress in any conditions and exploit the dynamic potential of its aluminium running gear with a new degree of supremacy. In other words: driving pleasure in the purest sense.

In common with the Audi RS 4, the new Audi S4 Cabriolet has the latest generation of quattro permanent four-wheel drive as standard. With the torque split of 40 (front wheels) to 60 at the rear wheels (manual-gearbox version), it provides even greater agility and a steering feel that is virtually free from feedback from the driveline.

The body: high standard of vibrational comfort

Even in the planning phase, Audi’s body developers worked systematically on the structure of the body and simulated its reaction to movements of the suspension and the mechanical assemblies. The result of this development process is that no disagreeable levels of either high or low-frequency vibration reach the passenger area on roads of any kind.

Both the highly rigid body and the quattro drive contribute towards its notably enjoyable drivability, because the S4 Cabriolet in conjunction with the direct steering response can be navigated round bends with millimetre precision. This is made possible by the special steering column connection that takes account of the vibrational behaviour that is specific to convertibles. The steering column mounting has an additional support, with the module cross-member linked to the cross-beam below the windscreen – measures that are decisive in keeping vibration at the steering wheel down to the lowest possible level.

Comprehensive safety

The Audi S4 Cabriolet’s A-posts are reinforced very effectively by means of high-strength tubes and their optimised structure – an indispensable source of extra safety if the car should roll over.

Sills with an optimised thickness and cross-section boost the occupant cell’s strength and optimise occupant protection. High-strength tubes are also used in the seat structure, as a means of protecting the occupants in the event of a lateral collision.

The doors in particular have to be designed with safety in mind. In conjunction with structural reinforcements in the sills and a strengthening cross-member below the rear seat, special impact absorbing beams in the doors ensure a high standard of safety. Crash resistance, even in the side impact test against a post, is on the same excellent level as the S4 saloon. At the car’s rear end, the double rear panel improves the rigidity of the body.

The comprehensive safety package contains seat belts with belt-force limiter and belt tensioner for all passengers, together with full-size front and side airbags. The side airbags integrated into the front seats are designed to protect the head and thorax.

If the car should roll over, a roll-over protection system in the double rear bulkhead adds to the occupants’ safety. In this case, two protective bars, controlled by sensors, are triggered behind the rear passengers within milliseconds. Together with the extremely rigid windscreen frame, they help to preserve survival space for all occupants if the car turns over.

The standard electronic stabilisation program ESP 8.0 with hydraulic brake assist provides for maximum active safety.

More than mere weather protection: the hood

The Audi S4 Cabriolet comes with the electro-hydraulic acoustic hood as standard. It opens entirely automatically in just 21 seconds – even faster than previously. By using new fabrics with a higher material density, the noise level inside is reduced to a level that scarcely differs from that in the Audi A4 saloon. This increases driving pleasure and comfort considerably when driving with the hood up.

Audi offers the hood in three exterior colours. The button only needs to be pressed once to either open or close the soft top. It is likewise possible to do this while the car is moving at speeds of up to 30 km/h.

The soft-top compartment can be height-adjusted by means of a lever in the luggage compartment. This increases the size of the luggage compartment considerably when the hood is closed. A heated, scratchproof glass window is just one of the reasons why the Cabriolet’s lined hood is entirely suitable for winter driving. Its structure, comprising three layers of precision-fitted textiles, assures effective protection against whatever the weather may have in store.

The hood is completely smooth on the inside. Together with the high-quality appearance of the surface, this look underlines the sporty, exclusive overall impression conveyed by the interior ambience.

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