Paris - December 13, 2005
Audi R10 world premiere in Paris V12 TDI engine produces over 650 hp
AUDI AG is once again one step ahead of the opposition: The inventor of
‘TDI’ will become the world’s first automobile manufacturer to fight for
overall victory with a diesel engine at the famous 24 Hours of Le Mans.
The all-new Audi R10, which was unveiled on Tuesday in Paris, is
powered by a totally new 5.5-litre, twelve-cylinder bi-turbo TDI engine,
which is extremely quiet and economical.
The Le Mans Prototype, with over 650 hp and more than 1,100 Newton
metres torque, significantly exceeds the power produced by the majority
of previous Audi racing cars – including that of its victorious R8
predecessor. Audi ventures into previously unexplored diesel-engine
terrain with the V12 power plant manufactured completely from
aluminium. As with the TFSI technology, which triumphed initially at Le
Mans before being adopted for mass-production, Audi customers should
benefit once again from the lessons learnt in motorsport.
"With the A8 4.2 TDI quattro, Audi already builds one of the most powerful
diesel cars in the world,” explained Prof Dr Martin Winterkorn, Chairman
of the Board of Management of AUDI AG, at the R10 presentation in Paris.
"The Le Mans project will help our technicians to extract even more from
TDI technology. Nowadays, every second Audi is delivered with a TDI
engine. We expect that the percentage of diesel engines will be even
larger in the future.”
The R10 prototype’s V12 power unit, which is equipped with two diesel
particle filters, is hardly recognisable as a diesel thanks to the engine’s
smooth running nature. The TDI engine’s specialities presented the Audi
Sport engineers with a whole list of challenges. The injection pressure
easily exceeds the 1,600 bar achieved in production cars. The usable
power band lies between 3,000 and 5,000 revs per minute – an unusually
low rev range for a racing engine. The driver must change gear in the R10
far less often than in the R8 because of the TDI engine’s favourable
The enormous torque of over 1,100 Newton metres does not only make
extreme demands of the R10 transmission system – even the latest
generation of engine dynamometers at Audi Sport had to be re-equipped
with special gearboxes capable of withstanding the unusual forces.
Additionally, radical changes to the chassis were also necessary. The
Audi R10 has a significantly longer wheel base than the R8. The overly
wide front tyres are, up until now, unique for a Le Mans Prototype. New
technologies were also implemented during the development of the
carbon-fibre monocoque. Chassis, engine and gearbox form an
extremely rigid, fully stressed unit.
"The R10 project is the biggest challenge ever to have been handed to
Audi Sport,” said Head of Audi Motorsport Dr Wolfgang Ullrich. "TDI
technology has not been pushed to its limits in motorsport yet. We are the
first to confront the challenge. The demands of such a project are
accordingly high. Long-term technology partners such as Bosch, Michelin
or Shell support us in our quest. Together we have the chance to write
new chapters in the history books of motorsport and diesel technology.”
The new Audi R10 successfully completed its first test at the end of
November. An extensive test programme, including the 12-hour race at
Sebring (USA) on 18 March, is scheduled before the 24 Hours of Le Mans
on 17/18 June 2006. The development team from Audi Sport is supported
by Reinhold Joest’s squad, which also performed this task during the R8
V12 TDI Engine made entirely from aluminium
The heart of the Audi R10 is a completely new V12 TDI engine with a
cubic capacity of 5.5 litres – the maximum permitted at Le Mans. Audi
ventures into previously unexplored diesel-engine terrain with power
exceeding 650 hp and torque of more than 1100 Newton metres from the
V12 power plant. "This engine is the specifically most powerful diesel
there is in the world and, up until now, the biggest challenge that Audi
Sport has ever faced in its long history,” explains Ulrich Baretzky, Head of
Engine Technology at Audi Sport. "There has never been anything
remotely comparable. We started development with a clean sheet of
The V12 TDI used in the R10 is the first Audi diesel engine with an
aluminium crank case. The cylinder-bank angle is 90 degrees. The V12
TDI has, like Audi production car engines, four valves per cylinder and
twin overhead camshafts. The fuel induction is made by a modern
"Common Rail System”. The injection pressure easily exceeds the 1600
bar achieved in production cars. The ignition pressures also reach values
never previously seen in any Audi engine.
The turbo pressure produced by the two Garrett turbochargers is limited
by the regulations to 2.94 bars absolute, the diameter of both engine air
intake restrictors, stipulated by the regulations, is 2 x 39.9 millimetres.
The engine management is controlled by the latest generation of Bosch
The engine’s power and the high torque are available to the driver
practically from idling speed – a speciality of diesel technology, to which
the Audi drivers must now become accustomed. The usable power band
lies between 3000 and 5000 revs per minute.
Unfamiliar to the driver at this early stage, is the low noise level and,
unique for a racing engine, the smooth running V12 TDI power unit. At
high speeds the powerful 650 hp engine can not be heard from the Audi
R10 prototype’s "open” cockpit while there is also hardly any vibration. On
the outside, the modern twelve-cylinder produces a faint, but sonorous
sound that quite possibly nobody would identify as a diesel power unit at
first. The new R10 can only be recognised acoustically as a diesel-
powered sportscar during the warming-up process or in the pit lane.
There are no visual signs that a diesel power unit is at work in the back of
the R10. It goes without saying that the V12 TDI is equipped with a pair of
diesel particle filters for the 24 Hours of Le Mans. Flashes of flame from
the exhaust, which are created by unburned petrol in spark-ignition
engines, are not seen coming from the R10.
One of the diesel engine’s biggest advantages is the low fuel
consumption, especially at part-throttle and overrun. However, when
compared to more classic circuits which demand a higher ratio of part
throttle, the lower specific consumption will hardly be noticeable at Le
Mans because the quota of full-throttle is almost 75 percent.
The enormous torque of over 1,100 Newton metres not only posed
previously unforeseen demands in the development of the R10 drive
train. Even the latest generation of engine dynamometers at Audi Sport
had to be reequipped with special gearboxes capable of withstanding the
Inside the V12 TDI, the extremely high pressures in particular create
forces never seen before in a racing engine. However, the main target of
the Audi technicians is to reach the reliability level of the R8, which never
recorded a single engine failure in the 77 races it has contested to date.