Audi R10 – The Detail
Are we looking at the winner of the 2006 Le Mans 24 Hours?
thinking long and hard about the details that became apparent during
a very busy three hours in Paris on Tuesday (December 13), it would
be hard to argue against the R10 winning on its Le Mans debut. But
that’s getting ahead of ourselves.
The launch was all about the car more than the programme.
The scene of
the launch was the Trocadero in the centre of Paris, overlooking
the River Seine and the Eiffel Tower. The first confrontation between
Audi and Peugeot diesels, below?
catering manager of the Trocadero is the grand-daughter (or great
grand-daughter) of Gustav Eiffel,” explained Audi UK’s
David Ingram, explaining how it came to be that Tom Kristensen drove
the R10 across the bridge over the Seine, gave it a quick rev or
two – very quietly – and then parked the brand new car
beneath the terrace.
Incidentally, David Ingram suggested that Audi Sport
UK wouldn’t be getting hold of an R10 “before 2007”,
which hinted at the (perhaps) lack of availability (to others) of
R10s in 2006. We’ll have to wait and see on that subject (see
The formal press conference was a very smoothly
conducted affair, led off by Professor Dr. Martin Winterkorn, Chairman
of the Board of Management of Audi AG, followed by Dr. Wolfgang
Ullrich, Head of Audi Motorsport, with interesting contributions
by seven-times Le Mans winner Tom Kristensen (the latter two both
have a remarkable command of European languages).
After the press conference it was a chance to grab
the full attention of the other Ulrich – Ulrich Baretzky,
Head of Engine Technology at Audi Sport.
the man who was responsible for the R8 engine – and the R10,
5.5 litre, V12 diesel is his ‘baby’ too. The diesel
engine is the heart of the R10, so here was the man to quiz about
the reaaly new feature of the new car. Baretzky did clarify that
oft-used statement about R8 engines never failing: “We never
had one fail in a race. It is different in testing, when you have
to take the engine to the limit…”
So it’s a 12 cylinder diesel – and a
very special racing engine in one important respect.
“It’s the first purpose-built, diesel
racing engine. Every other racing diesel has been developed from
a production engine.”
So why did you choose 12 cylinders? (perhaps the
first question should have been – Why did you choose to build
a diesel? – but we’ll get to that answer in due course)
“We carried out a feasibility study with 10
and 12 cylinder engines. Because the combustion pressures are so
high, it is better to distribute those pressures across 12 cylinders
rather than eight or ten.”
Baretzky (right) mentioned a figure for the pressures within a production
diesel of 160 bar, “but we are far beyond that with the R10.”
Similarly the injection pressures of over 2000 bar
are well beyond the 1600 bar of production engines.
So huge internal pressures within the combustion
chambers (and in the common rail injection system), but isn’t
the V12 a massive engine as a result of having to cope with those
“If you took a fuel injection (petrol) engine
of the same size, the weight of the two would be similar. (Or put
another way) if you took the 3.6 litre engine from the R8 and added
four more cylinders, then you would have the same weight.”
Thinking about that remark, he’s suggesting
that cylinder for cylinder, the two engines are the same weight,
it’s just that one is a 5.5 V12 (5.5 is the maximum allowed
for a diesel), the other a 3.6 V8.
The diesel engine is all-aluminium, rather than,
say, an iron block, so the Audi engine wizards have managed to keep
the weight down as a result. “We have designed it in a very
clever way” (no elaboration on that point, obviously), yet
are still very confident that the V12 will be as reliable as the
“That has to be the target – to make
this engine as reliable as our other engines.”
Ulrich Baretzky then emphasised a point made by
Prof. Dr. Winterkorn and Dr. Ullrich – that Audi is heading
down the diesel road because that will allow the company to improve
its road-going diesel engines, which will benefit the customer.
“Nowadays, every second Audi is delivered
with a TDI engine,” said Prof. Dr. Winterkorn, earlier. “We
expect that he percentage of diesel engines will be even larger
in the future.”
Doubtless a Le Mans win or two wouldn’t exactly
harm sales of diesel-powered Audi road cars.
The power and torque figures of the V12 (650 bhp
and 1100 Nm, with a power band between 3000 and 5000 revs) are staggeringly
impressive – but just like the R8, but more so, the diesel
isn’t going to be very stimulating aurally.
“From the figures and from the physics, a
diesel engine for racing has to be low-revving,” says Urich
Baretzky. “I’ll be very interested to see how anyone
else gets on with a high revving diesel engine…”
A low revver has advantages in fuel economy and
fewer gearchanges, he believes, and he predicted that “we
are calculating two more laps than with our R8 engine.” Baretzky
left that statement deliberately vague.. two more laps than the
original R8, or the FSI R8 with a 90 litre tank, or the more recent
car with 80 litres?
He also commented that “we know from the R8
that the driver has a big influence on the economy, and we will
face a similar situation with the diesel.”
When Tom Kristensen revved the V12 out on the public
road earlier, there was no sign of any smoke from the engine.
smoke at all. That is a combination of the very efficient combustion
and the particle filters (two). We won’t need to change the
filters during a 24 hour race – in fact, they clean themselves.
I’m really interested to see how long they will last (in an
Bartezky summed up his design philosophy for this
engine as “no flames, no smoke, no noise. No one wants a screaming
engine in a road car, and the race engine will be no different.
I don’t like screaming engines.”
F1 seems to have no appeal to these people.
Frank Biela is the only man to have driven the R10
in anger (in a shakedown test on November 29), and that test was
to “gather a lot of data about the car. That was the first
time the engine had run in the car, on a track.”
Baretzky admitted that after that first test that
he and his engineers do not yet have any sense of the outright speed
of the car – and as usual, they won’t know what that
speed is at Le Mans (except on the computer), until the Le Mans
test day on the first weekend in June.
Last two points from Herr Baretzky.
Audi have used a production diesel engine as the basis for the Le
“We tested the 4.2 litre V8 production engine,
and it was tremendously reliable – but it’s a cast iron
engine. We wanted to make a big step forward with the race engine
– that’s how we do things.” So perhaps Audi production
engines will be much lighter in future.
“Have you seen my model,” he asked?
From within a cardboard box, he proudly revealed
his model 3.6 twin turbo V8.
“It’s not as tough as the real one –
I’ve damaged it already.”
Allegedly, someone was taking photographs of the
petrol engine at Le Mans, and Herr Baretzky agreed to forward the
CAD drawings of the V8, so the modeller had every detail needed
to make the model engine that the Head of Engine Technology is shown
So what about
the rest of the car?
has the standard LMP1 design cues (with some unique features), it
has a longer wheelbase than the R8 (thanks to the longer engine),
it was built by Dallara again, it has “overly wide”
front tyres, to reduce understeer, the chassis is (largely) the
bodywork (“the majority of the carbon-fibre parts belonging
to the R10 monocoque are now suspended directly in the airflow and
therefore require no additional fairings”), the power steering
is now electric rather than hydraulic, the gearbox’s internals
“can be changed within a short period of time”, data
logging information is displayed on the car’s steering wheel,
and an electro-pneumatic shift system changes the gears (of the
Xtrac derived gearbox, which is lighter than in the R8, despite
having to handle all that torque).
Basically, the R10 chassis seems to have all the
strengths of the R8 – but better.
impressive just how the engine keeps on pushing even in the high
gears,” said Frank Biela, after that shakedown test at the
end of last month.
We’ve been sure for months that it was going
to be a diesel – but Audi Sport has been able to keep the
details a secret, since settling on a 5.5 litre V12 in September
This project is a huge step forward, and although
it is over two years old already, everyone at Audi Sport is very
conscious of the fact that the 2006 Le Mans event is only seven
months away – and the R10 has had only a shakedown.
But every day between now and Le Mans “is
planned”, and the engine has already covered over 1000 hours
out of the car. That time on the dyno. will be tripled before Le
Mans: you really can’t imagine the engines being any kind
of a weak area next June.
Neither will the team behind the R10: Reinhold Joest
will be responsible for running the pair of cars at Sebring and
But as regards R10s running elsewhere in 2006, “nothing
has been confirmed as yet,” said Herr Ullrich. He wouldn’t
confirm Audi’s DTM plans (or not) either.
So there’s more news to come on this project,
specifically any other 2006 programmes (ALMS, Le Mans Series and
Japan are being considered), but that’s just about all the
news for now. It was quite an eventful day.
So does it scare
the pants off everyone else? Is this why Henri Pescarolo was so
bitterly disappointed not to have grabbed his Le Mans chance in
2005? Has the R10 made France its second home already?