In the UK, a car covers 3300 miles every six months on average. At Le Mans in 2010, Audi’s winning R15 TDI plus race car covered more than that distance in just 24 hours at an average speed of almost 140mph. With turbochargers running at 1000C and cornering forces that exposed drivers to 3G of lateral force – equivalent to that experienced by a NASA Space Shuttle crew during take-off – can you envisage the relentless torture that the suspension, steering, engine, gearbox, brakes and every single nut and bolt had to soak up in the pursuit of victory?
Of course, by capturing 1005 live data channels from the car during the race, the Audi Sport engineers didn’t leave anything to the imagination. ‘Every time the car went into the garage after a race, it would always come back stronger, one way or another,’ recalls Danish driver Tom Kristensen, a nine-time Le Mans victor. ‘That is how it was at Audi. There was always a competition to take the information from the race and see who could come up with ideas, and then we would use them to see how we could improve together. And it wasn’t just about making our race cars even faster and more efficient. We also competed to develop innovative technology to improve Audi’s road cars. That was just as important as winning races and championships.’
Here we take a look at six technologies, developed during 18 years of competition in endurance racing, that not only helped the four rings win Le Mans 13 times but have gone on to benefit Audi drivers to this day.
FSI – WINNING IN A HIGH-PRESSURE ENVIRONMENT
The first Audi R8 race car – which later gave its name to the R8 road car – featured a very powerful twin-turbocharged V8 engine producing in excess of 540PS. But it was, as Kristensen explains, a bit of a wild ride. ‘The engine had a lot of turbo lag, followed by a very aggressive response. It was like a delayed time bomb – nothing, nothing, and then BOOM!’ This didn’t prevent the four rings from winning in 2000 – but back at headquarters in Germany, Audi’s engine experts set to work in great secrecy to develop a smoother solution for 2001.
In an industry first, Audi’s new Fuel Stratified Injection (FSI) technology injected petrol directly into the engine’s combustion chamber, and at a pressure up to 20 times higher than that of a conventional petrol engine. This ultra- precise metering of fuel enabled the 2001 R8 to travel an average of one lap further on each tank of petrol. ‘The FSI system was very helpful for the driveability of the engine, and it was also a lot more efficient and an excellent development for road cars,’ explains Kristensen, who swept to his second victory with Audi in 2001. The technology was transferred to the A4 road car later that year. Today, drivers of all Audi petrol-engined cars continue to reap the benefits of more power, greater fuel efficiency and smoother throttle response provided by the battle-proven FSI system.
TDI – FORTUNE FAVOURS THE BRAVE
Audi caused a major shock when, in 2006, it announced it was going racing with a TDI turbodiesel engine. And it wasn’t only the rest of the world that thought it was a crazy idea – Audi’s racing drivers thought it was crazy too. ‘It was certainly not something we expected,’ recalls Kristensen, with classic understatement. ‘But we knew that once Audi Sport’s then Head of Engine Development, Ulrich Baretzky, got an idea, he would make it work.’
And work it most certainly did, with the Audi R10 TDI becoming the first diesel-powered car to win the Le Mans 24 Hours in 2006, before repeating the feat again in 2007 and 2008. In this instance, it was arguably a case of Audi’s road cars paving the way for success on the racetrack, as the ground-breaking R10 TDI was based on well over a decade of Audi TDI turbodiesel technology (the very first TDI road car was launched by Audi in 1989). However, winning at Le Mans enabled Audi to accelerate the development of its turbodiesel technology – as demonstrated by the ever more fuel-efficient Le Mans-winning R15 TDI plus and R18 TDI race cars, and the TDI road models that followed.
QUATTRO – KEEPING A FIRM GRIP ON THE TRACK
In the 1980s, Audi’s famous quattro all-wheel-drive technology secured four world championships on snow, ice, mud and gravel rally stages all over the globe. And it had proven successful on racetracks too; so successful, in fact, that it effectively led to the banning of all-wheel-drive systems in most saloon-car race series after the A4 quattro Super Touring won seven championships in a single year. Even so, the Le Mans 24 Hours, with its 205mph-plus speeds, was another challenge altogether for Audi’s R18 e-tron quattro.
A TDI engine drove the car’s rear wheels while, in certain circumstances, two electric motors delivered drive to the front wheels: as the brakes were applied, the front axle recovered kinetic energy, which was fed back to the front wheels at speeds above 75mph as the car exited a corner, enhancing grip, traction and stability. ‘You didn’t feel it so much until you switched it off,’ recalls Scotland’s Allan McNish, a triple Le Mans winner. ‘But then you thought, “Hmm, can I have that power and traction back now?”.’ Driving with Kristensen and France’s Loïc Duval, McNish won the 2013 Le Mans in the R18 e-tron quattro.
E-TRON – ELECTRIFYING THE FUTURE
Audi’s all-electric e-tron SUV arrived in the UK in 2019. But, seven years before that, the Audi R18 e-tron quattro was busy pounding around Le Mans, day and night, on high-speed 205mph development duty in the epic 24-hour endurance race. To the dismay of Audi’s rivals, the e-tron technology – which was used to provide additional drive to the front wheels in certain circumstances while the rear wheels were powered by a diesel engine – didn’t seem to need a lot of improving. The R18 e-tron quattro won on its debut in 2012 and repeated this feat in 2013 and 2014. Amazingly, on Audi’s final Le Mans outing in 2016, the R18 used 46 per cent less fuel than the 2006-winning R10 TDI race car. Today, Audi continues the rapid advancement of its e-tron technology on the track in the all-electric, single-seater Formula E series. And the lessons learnt are fed straight back to the ever-expanding range of all-electric Audi e-tron road car models, such as the e-tron SUV and e-tron Sportback.
VIRTUAL MIRRORS – KEEPING A CLOSE EYE ON HAZARDS BEHIND
The e-tron SUV was the first Audi production car to offer the option of virtual mirrors – but note the word ‘production’ there. The virtual door mirrors on Audi’s all-electric SUV replace traditional glass mirrors, with cameras that stream a view of what’s behind onto displays mounted within the front doors. Considerably narrower than standard mirrors, they help to further reduce both aerodynamic drag and the impressively low level of wind noise.
Once again, though, this technology was trialled on an Audi race car at Le Mans, appearing for the first time in 2013. Normally, with no rear window, top-level closed-cockpit Le Mans cars afford the driver no rear view, but Audi solved the problem by mounting a small rearward facing camera on top of the car’s roof, with the signal transmitted to a 6.8-inch Active Matrix Organic Light Emitting Diode (AMOLED) diagonal display inside the cabin. The digital rear-view mirror eliminated the blind spot behind the car, and made it easier for Audi’s drivers to know when to pull back into their lane after overtaking a slower car.
LIGHTING TECHNOLOGY – ILLUMINATING THE ROAD AHEAD
What better environment could there be in which to develop new headlamp technologies than the long, dark night of the epic Le Mans 24 Hours? Audi was the first manufacturer to introduce LED daytime driving lights at the 2006 race, and it won with a combination of Xenon and LED headlights in 2010, before switching to full LED headlamps to take victory again in 2011. By 2013, Audi were deploying Matrix LED headlights, which provided a beam of light more than 800 metres long – an 85 per cent increase on 2006. The following year, Audi raised the bar higher still with the introduction of laser lights, which provided an even longer, broader and more intense spread of light.
‘Over the years at Le Mans, lighting technology improved greatly,’ remembers Kristensen. ‘The illumination provided by the laser lights was incredible and, of course, like so much of the innovative technology we developed at Le Mans, all those lighting systems became available on Audi’s road cars too.’