Review
Mid-engined supercars? They're usually the work of Ferrari and Lamborghini, Lotus or Porsche. You don't expect an extreme car like this to come from a premium German marque like Audi, which mostly specialises in classy, well-made and rather grown-up saloons, with odd indulgences like the TT. Apart from being the most expensive model Audi makes - as well as the fastest - the R8 is all about the thrill of driving for the sake of it, and it's a high-end thrill at that.
This baby Ferrari is quite unlike anything else Audi makes, not only in its technical make-up but also the way it drives. Not only does it deliver all that you'd hope for from a 420bhp mid-engined supercar, but it is also more impressively developed than any other car Audi makes, from modest 1.6 litre A3 hatch through to that W12 SUV behemoth that is the ultimate the Q7. So what do you get for your £80k? Well, the heart of the car, a potent, high-revving V8, is on display for all to see beneath the glass pane of the engine lid, Ferrari-style. It drives all four wheels via a six-speed transmission that is either semi-automatic and triggered by paddle shifts, or a conventional manual. This layout provides the 44:56 front:rear weight distribution that is the key to the ultimate in on-road manoeuvrability, the improved balance of the car making it more willing to change direction than squirming politician.
But it takes more than this to create a competitive supercar. Body rigidity, a low centre of gravity, excellent aerodynamics and sophisticated suspension are just as vital as the raw and sexy drama that makes you look twice. First, though, the substance. The R8's bodyshell is of lightweight aluminium - as with the luxury A8 saloon - and weighs a spectacularly low 210 kilos. It lacks nothing when it comes to rigidity - which is absolutely vital in a 187mph car that is all about cornering - or safety. The body is largely hand-built, and to an exceptional level of accuracy, every bodyshell laser-measured in 220 places, every single component checked to within a tenth of a millimetre.
The R8's drag coefficient is not so impressive at 0.35 - some saloon cars score as low as 0.28 - but this is because the bodywork must generate downforce to keep the car pressed onto the road at speed. In fact, the R8's drag coefficient is the lowest among sports cars that generate downforce, which is produced by an under-floor diffuser and a rear spoiler that extends at 62mph, and does not retract until the car's speed has dropped below 22mph.
The R8's suspension system is the classic race-car double wishbone all-round, but its shock absorbers are unusual for optionally being magnetically adjustable (as they are on the TT), while the all-wheel drive system is configured to deliver between 10 and 35 percent of the engine?s torque to the front wheels. There is also a limited-slip differential for the rear axle, and switchable ESP is standard.
Big, composite brake discs are stud-mounted to the wheel hubs, improving heat dissipation, while ceramic discs are available as an option - they chop a surprising 20 kilos from the R8?s weight, and are claimed to have an operating life of 186,000 miles.
You can choose either a six-speed manual transmission or a robotised paddle-shift semi-automatic - called R tronic, it has been borrowed from sister company Lamborghini's Gallardo - and costs extra. Driving all this is a compact 4.2 litre V8 featuring a dry sump, its lubricating oil supplied from a separate tank. Eliminating the conventional oil sump allows the engine to sit significantly lower within the car's frame for an improved centre-of-gravity, improving the car's cornering prowess. This engine is designed to be high-revving - it runs out to 8250rpm - and delivers its peak power at 7800rpm. Its quad cams are variable profile, and the intake system is variable length too. The V8's exceptionally high engine speeds have necessitated the fitment of the most powerful microprocessor available for this task, known as Green Oak, incidentally.
