Audi created motorsports history again at the 2012 24 Hours of Le Mans, with its Honeywell turbocharged R18 e-tron quattro becoming the first-ever hybrid race car to take the checkered flag in the world-famous endurance event.
Marcel Fässler (CH), André Lotterer (D) and Benoît Tréluyer (F) in the No. 1 Team Joest R18 car repeated their success of 2011 while three other Team Joest R18 race cars finished second, third and fifth.
In a race packed with drama and incident, Audi relinquished its lead position only once, when one of the two Toyota TS030s headed the field and promised to ignite the much-anticipated battle of the hybrids. Unfortunately the rivalry was brought to an end by the early retirements of the naturally-aspirated gasoline hybrid cars…and from that point on it was Audi all the way.
Celebrating the success, Head of Audi Motorsport, Dr. Wolfgang Ullrich, said: “This is a historic victory for Audi. We were the first to win Le Mans with a direct-injection turbo gasoline engine and the first to be successful with a diesel engine. Audi is now the first brand to have achieved victory with a hybrid vehicle – and on the first run.”
During the race, the Audi R18 cars, equipped with 3.7L V6 single-turbo diesel engine, exemplifies the benefits of engine downsizing made possible by innovative technologies. Compared to its predecessor R15 (with 5.5L twin-turbo diesel engine), the Audi R18 points to a future – on and off the race track – characterized by smaller, better performing turbocharged engines.
“In 2006, Audi won at Le Mans with a V12 engine which had 5.5 liters of displacement,” said Ulrich Baretzky, head of Race and Special Engine Development at Audi Sport. “Now, only six cylinders are operating in the Audi R18 and, in line with the regulations, displacement has been reduced to 3.7 liters. This means that, in total, the engine in the current vehicle generation makes do with half of the cylinders, has 32 percent less cubic capacity and yet it has still been possible for the R18 to improve its lap time by 2.8 percent.”
“The turbocharging concept of the Audi R18 has been a particularly well-kept secret up to now,” said Mr. Baretzky. “The engineers designed a central mono turbo system in the inside V of the engine which, in combination with the inboard exhaust manifolds, makes particularly efficient use of the laws of physics. The mono turbocharger thus has to put through a similar amount of charge air for over 375 kW (510 hp) as the two previous turbochargers in the V10 TDI for 404 kW (550 hp).”
After helping Audi R18 race to victory at Le Mans last year, Honeywell Motorsports Team was determined to go even further. Closely collaborating with the Audi team, engineers opted for lighter-weight materials, developed more efficient aerodynamics, and improved turbo system inertia, helping set new acceleration benchmarks. In addition, the stringent testing undertaken by both Honeywell and Audi was reflected in the impressive turbo reliability over the race distance – all achieved while delivering better fuel economy than in 2011.
Honeywell’s ground-breaking racing VNT turbo integrates snugly into the center of the R18 V6 diesel engine, contributing to extreme efficiency in space utilization which, when coupled with the new lightweight materials, helps lower the center of gravity. Another unique feature of the VNT racing turbo is its embodiment of the proven VNT technology and gasoline high-temperature capabilities. Today, it is the only VNT turbo in the world that can operate in temperatures above 1000oC.
“Audi has now won this event 11 times since 2000 and always with the help of Honeywell Garrett turbochargers.” said Mr. Baretzky. “The success of this partnership has been confirmed by the winning streak in the world’s toughest endurance race, the 24 Hours of Le Mans.”
Photos courtesy of Audi