If you don’t fancy the chances of the Toyota TS030 Hybrid winning at Le Mans on its first attempt, then you’re looking at the car that will probably be taking the chequered flag at La Sarthe on June 17 2012. It’s the Audi R18 E-tron Quattro, a hybrid version of the Audi R18 TDI that won the 2011 Le Mans 24hrs.
Audi R18 E-tron Quattro? What’s the E-tron and Quattro bit about?
It means the Audi R18 has become a hybrid racecar. When the R18 was first unveiled Audi revealed that it had been engineered to take an electric powertrain, and it’s now got that system. We’ll see the E-tron Quattro technology on Audi road cars in the future, but the R18 reverses the system we’ll see on the road: rather than the front wheels being driven by an engine, and electric drive going to the rear, the R18 sends power from its diesel V6 to the rear, while the electric motor drives the front axle.
Le Mans rules limit diesel race cars to forced-induction 3700cc engines, which means the R18 E-tron Quattro runs the same 503bhp turbocharged 3.7-litre V6 as the non-hybrid R18, though it's allowed a larger 71-litre fuel tank (non-hybrid diesels: 65 litres). As for electric part of the powertrain, kinetic energy is recovered on the front axle during braking and fed into a flywheel accumulator, from where it’s used to boost acceleration above 75mph. Road cars won't have the flywheel system, which is suited to race cars.
Work on the Audi R18 E-tron Quattro only started on February 2010 so Audi is being cautious: ‘This is a relatively short cycle for a technology that has never been tested in motorsport and which still doesn’t even exist in production,’ said Dr. Martin Mühlmeier, head of technology at Audi Sport. ‘The challenge is correspondingly big.’ So just to cover itself, Audi will not only field two R18 E-tron Quattros at the 2012 Le Mans 24hrs, but also two 2012-spec (and non-hybrid) Audi R18 Ultras. Upgrades include a new gearbox with a carbonfibre housing, which Audi says is a first in endurance racing.
The Audi R18 E-tron Quattro (along with the 2012-spec R18 TDI – and the Toyota TS030) will makes its race debut on 5 May 2012 at the 6hrs of Spa, and will then fight for victory at the 2012 Le Mans 24hrs on 16-17 June. One of the R18 E-tron Quattros will be driven by last year’s Le Mans-winning trio of Marcel Fässler, André Lotterer and Benoît Tréluyer, while Dindo Capello, Tom Kristensen and Brit Allan McNish will pilot the second car. Between them, this second trio have 13 Le Mans wins. Four R18s (two hybrids, two non-hybrids) will contest Spa and Le Mans, and after that Audi will enter one R18 Ultra and one R18 E-tron Quattro in the FIA World Endurance Championship (WEC).