Audi is presenting a revolution in the top class at the Detroit Auto Show 2008 – the first 12-cylinder diesel engine in a high-performance roadgoing sports car. The V12 TDI with a displacement of six liters powers a concept car based on the Audi R8. This unit generates a huge 500 bhp and 737.56 lb-ft of torque. Audi is writing a new chapter in diesel technology with this power unit. Equipped with the expertise that Audi has built up through its motor sport activities, the R8 V12 TDI in matt “Grace Silver” embodies superb road handling, pioneering technology and fascinating design.
The V12 TDI is closely related to the engine in the Audi R10, the two-time Le Mans winner – so it catapults the Audi R8 into supercar terrain concerning performance too. It sprints from zero to 60 mph in just 4.2 seconds and its top speed is well over 186.41 mph. The peak torque, reached at only 1,750 rpm, paves the way for effortless acceleration that is unrivaled even at this level.
The Genes of the Winner
Thanks to their high performance and pulling power, all Audi TDI engines are ultra-dynamic sources of power. The brand has often enough demonstrated its sporty character in its production cars, especially the six- and eight-cylinder 3.0 TDI and 4.2 TDI. Audi has also been writing a new chapter in its success story on the racetrack since 2006. The diesel engine in the R10 sports prototype won its very first endurance race at Sebring, Florida, when it was pitted against an entire field of gasoline-engined challengers. But its most crucial victories were surely in 2006 and 2007 in the 24 Hours of Le Mans, when it simply outclassed the international elite.
The V12 TDI race engine in the R10 produces over 650 bhp from a displacement of 5.5 liters, giving it the potential for a top speed as high as 205.05 mph depending on the gear ratios. Its power and sturdiness immediately impressed both fans and experts, who were impressed by its restrained noise level. Unusual for a race engine, this powerful Audi diesel makes barely more than a whisper.
Audi’s engineers were in an ideal position to use their experience building the racing engine to develop the road version. Like the other power units in this range, the distance between cylinder bore axes on the V12 TDI is 90 mm (3.54 in.). Yet its included angle is 60 degrees, not 90 degrees. This means no free inertial forces or mass moments of inertia can occur with the V12. The results are refined in every respect.
The two turbochargers, which generate up to 2.6 bar of boost pressure, play a crucial role in producing the huge torque of 737.56 lb-ft that the V12 TDI maintains from 1,750 rpm to 3,000 rpm. In developing 500 bhp, the diesel achieves a specific output of 84.3 bhp per liter displacement.
Two large intercoolers reduce the temperature of the compressed air. The V12 has a twin-pipe exhaust system with two particulate filters. The intake system is similar in structure with one air cleaner per cylinder bank, with an airflow meter behind it. Two control units, sharing the workload in a master/slave principle, manage events in the engine.
The R8 V12 TDI concept with matt “Grace Silver” bodywork looks even wider and more resolute than the core model. It shows its potential through its muscular proportions, accentuated wheel arches and even larger air apertures. The rhombuspattern cover on the air inlets and outlets is the hallmark of Audi’s sporty top models and a familiar feature of the current RS generation.
Typical of the side view of the R8 is the sideblade. Much wider in the bottom third, it visually accentuates the engine’s position as well as acting as an enlarged air deflector.
The continuous aluminum spoiler lip that connects the front and rear diffusers with side air baffles below the enlarged sills also pays tribute to this version’s highly developed dynamic talents.
Ergonomic and Elegant Interior
The interior’s design is as sporty and exclusive as the exterior: the characteristic element here is the monoposto – an expansive arc running around the steering wheel and instruments, connecting the driver to the car. The interior consequently picks up on the dynamism of the R8 V12 TDI concept and gives it tactile expression in a form that is accessible the moment you climb in.
The start/stop button for the engine and the Drive Select switch with the Dynamic/Sport/Race settings are arranged on the steering wheel. The latter controls the engine and transmission electronics as well as the magnetic ride dampeners in each of three different modes.
In Race mode, the instrument lighting changes from white to red. The navigation system shows a combined display with lap timer and navigation information for the racetrack being driven. Or supplementary information such as centrifugal force and boost pressure can be called up.