Unveiled at the 2008 Detroit Motor Show, the Audi R8 V12 TDI Concept has an extremely muscular and aggressive design, with accentuated wheel arches and larger air intakes.

A characterizing design element is the transparent roof dominated by a NACA air duct that reminds of the 1991 Audi Avus Concept.

The V12 TDI engine has a displacement of six liters and a 60 degrees angle between cylinder banks.

It delivers 500 hp and 1,000 Nm (737.56 lb-ft) of torque, reached at only 1,750 rpm. The unit is coupled with a six-speed manual transmission.

The R8 V12 TDI is equipped with the quattro permanent all-wheel drive system, with power distributed variably between the front and rear wheels from a starting ratio of 40:60 to optimize the handling.

Performace figures are a 0-100 km/h sprint in 4.2 seconds and a top speed well over 300 km/h (186 mph).

Exterior Design

The R8 V12 TDI concept with matt "Grace Silver" bodywork looks wider and more resolute than the core model.

It shows its potential through its muscular proportions, accentuated wheel arches and larger air intakes.

The rhombus pattern 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.

Another new aspect is the glass roof of the passenger compartment with two large transparent sections.

These, together with the glazed engine compartment behind, create a radically new formal element.

The NACA duct in the middle of the roof is a accelerates the air drawn in here for the two cylinder banks of the V12 TDI engine.

The V12 TDI is displayed as the beating heart of this sports car, like a work of art. Its look, underscored by the air deflectors located beneath the restyled rear glass lid, differs clearly from its production counterpart.

The engine can even be seen after dark, when white LEDs illuminate the engine compartment – as on the production R8 version. This "showroom" can additionally be fully lined in carbon fiber, for a particularly exclusive look.

The continuous line running from the front apron across the wheel arches and flanks to the tail end, then back down the other side, is one of the latest design hallmarks of the Audi brand. This "loop" naturally encompasses the air apertures, the headlights and the taillights.

The Audi R8 V12 TDI Concept debuts at the 2008 Detroit Motor Show

Interior

Inside, the characteristic element here is the monoposto – an expansive arc running around the steering wheel and instruments, connecting the driver to the car.

The compact three-spoke sport steering wheel remains the focal point of the car's controls and features a a flat lower edge that facilitates entry and exit for the driver.

Covered in Valcona leather and with a diecast magnesium core, the steering wheel integrates the start/stop button for the engine and the Drive Select switch with the Dynamic/ Sport/Race settings.

The latter controls the engine and transmission electronics as well as the magnetic ride dampeners in each of three different modes.

Compared with the production version, the R8 V12 TDI concept's interior has much larger aluminum applications, especially around the center console. The many carbon fiber elements give the interior a decidedly sporty feel.

Technology

The R8 V12 TDI is based on the ASF (Audi Space Frame) technology: the body's supporting structure is made of extruded aluminum sections and die-castings. Aluminum panels are incorporated into this skeleton to form a positive connection and perform a load-bearing role.

Each individual component of the ASF space frame is optimized for its specific task by the use of widely differing shapes and cross-sections, combining maximum stability with minimal weight.

The entire bodyshell of the study car weighs just 210 kg (462.97 lbs.).

The extended rear spoiler is larger than on the production version, and together with the two large-format diffuser apertures in the rear bumper and the fully clad diffuser underbody contributes to the car's aerodynamic efficiency.

The V12 TDI crankcase is made from gray cast iron with vermicular graphite – a high-tech material about 40 percent more rigid and 100 percent more fatigue-resistant than gray cast iron.

The valves are actuated by low-friction roller cam followers; the compression ratio is 16.0:1. Map-controlled swirl variation of the combustion air has been adopted from the V6 and V8 TDI engines.

The two new dual-piston high-pressure pumps form part of the common rail injection system supplied by Bosch. They build up a pressure of up to 2,000 bar in the rails.

The number of injection processes per operating cycle can be varied across a wide range thanks to piezo technology – reaching as many as five fuel injection operations in the case of the V12 TDI.

The two turbochargers are located on the outside of the engine's V, each of them supplying one bank of cylinders. They have variable turbine geometry and generate up to 2.6 bar of boost pressure.

The Audi R8 V12 TDI concept already fulfills the Euro 6 emissions standard that is likely to take effect in 2014.

About the Audi R10 TDI

The V12 TDI is closely related to the engine in the Audi R10, the two-time Le Mans winner.

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.

The V12 TDI race engine in the R10 produces over 650 hp from a displacement of 5.5 liters, giving it the potential for a top speed as high as 330 km/h (205.05 mph) depending on the gear ratios.

(Source: Audi)