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Another Audi sports model with a strong personality is about to leap from the
starting grid in Australia - the Audi S4 Cabriolet. This car combines the
qualities of the Cabriolet with the powerful V8 engine from the Audi S4 and the
dynamic handling of the company’s outstanding quattro driveline.
Design and equipment
The new Audi S4 Cabriolet expresses its supremacy by adopting a deliberately
restrained appearance – a wolf in sheep’s clothing. A closer look, however,
reveals that this stylish, sporty body is indeed subtly different in its basic
form and proportions to its sibling - the Audi A4 Cabriolet.
The front bumper features large air inlets, the xenon headlights have a
titanium-coloured surround behind the glass and the outside mirror housings have
been given an aluminium finish. A glance at the rear reveals the powerful
exhaust tailpipes on both sides that are so typical of the Audi S models. The
Audi S4 Cabriolet runs on 18-inch cast aluminium wheels of S design with 235/40
R 18 tyres.
Inside too, this Cabriolet is immediately identifiable as an S4. The
instrument cluster has the grey dials that are characteristic of S models and
special needles. There is a choice of carbon fibre, piano finish, brushed
aluminium and birch wood for the inlays. The car’s sporty character is
emphasised by the three-spoke leather-covered sports steering wheel with S
emblem. There are shift paddles behind the steering wheel on cars with the
6-speed tiptronic transmission.
The Alcantara and leather sports seats, with lumbar support and adjustable
thigh support, can be electrically adjusted in several directions, providing
firm lateral support and excellent comfort on long journeys.
The V8 engine - a virtual torrent of power
The Audi S4 Cabriolet’s eight-cylinder engine develops 253 kW (344 bhp) at
7,000 rpm, and delivers a massive 410 Newton-metres of torque to the crankshaft
at 3,500 rpm. Such impressive figures are a sure sign of the superiority of this
large-capacity, naturally-aspirated engine.
Possibly even more impressive than its peak power output is the immediacy
with which it responds to every movement of the accelerator pedal, and its
remarkable willingness to run freely up to high revs. The exhaust system
produces a deep, sporty note, always present but never obtrusive.
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.
The eight-cylinder engine surprises the onlooker in yet another way. It is
shorter and more compact than any other engine of this type and size, measuring
only 464 millimetres from front to back. Audi’s engine developers achieved this
by moving the chain drive for the camshafts and auxiliaries to the output end of
the engine, thus reducing its overall length by 52 mm. 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.
Power is delivered to the 18-inch cast aluminium wheels via a 6-speed
tiptronic transmission with dynamic shift program, plus an additional Sport
program. Shift paddles on the steering wheel combine sports-style driving with
the convenience of an automatic transmission, and are therefore ideal for
smooth, relaxed travel in an open-topped car.
The sports suspension - aluminium makes the car agile
The lightweight aluminium chassis 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.
Ride comfort also benefits from this ingenious suspension design, since low
unsprung weight makes the suspension more responsive to road-surface
irregularities.
The S4 Cabriolet has firm sports suspension settings – an important
precondition for agility and thus for pure driving enjoyment.
The servotronic steering is a standard feature, varying the degree of power
assistance according to road speed so that the correct combination of steering
precision and light action is always obtained.
The quattro driveline - driving fun and ample traction
The new Audi S4 Cabriolet has quattro permanent four-wheel drive as a
standard feature. It can therefore translate engine power into optimal progress
in any conditions and exploit the dynamic potential of its aluminium chassis
with a new degree of supremacy. In other words, driving pleasure in the purest
sense.
The body - a benchmark for comfort
Even in the early planning stages, 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 unpleasant levels of either high- or
low-frequency vibration reach the passenger area on roads of any kind.
Even driving pleasure benefits from the body's high rigidity because the
direct steering enables the S4 Cabriolet to be guided extremely accurately
around corners. 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.
Measures designed to increase strength and rigidity also affect the choice of
material grades and joining techniques. For instance, high-strength and
ultra-high-strength panels account for more than 50% of the weight of the
bodyshell.
Optimised wall thickness in conjunction with improved-quality weld points
help to boost the structural durability of the body significantly. The body is
in addition reinforced by a rigidly bolted-on subframe at the front, with
additional diagonal struts at the front and rear.
A high level of crash protection
The Audi S4 Cabriolet’s A-posts are optimised in cross-section and contain
high-strength reinforcing tubes – a most important safety feature 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 enhancing occupant safety 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.
Comprehensive safety
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, an active 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 with hydraulic brake assist
provides for maximum active safety.
More than mere weather protection - the Cabriolet hood
An electro-hydraulic hood, which closes at the touch of a button in under 30
seconds, is standard equipment on the Audi S4 Cabriolet. The button only needs
to be pressed once to either open or close the soft top. The side windows move
down and up again to aid the process.
A lever in the boot raises or lowers the hood compartment, so that a much
larger luggage space becomes available 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. It has three
layers of cloth and is sewn to high standards of accuracy to ensure maximum
occupant protection, resist climatic effects and provide a standard of acoustic
insulation worthy of a premium car such as this.
The hood's linkage is barely visible when the hood is in the raised position;
the tautness of the hood and the cushioning prevent any "tent ridge" effect. The
shape of the roof as a harmonious component of the Cabriolet design is preserved
at all speeds. The hood is also completely smooth on the inside. Together with
the high-quality appearance of the surface, this look underlines the luxurious
overall impression conveyed by the interior ambience.
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