Audi boss praises Le Mans rules

Ullrich said that the possibility to run diesel fuelled cars at Le Mans meant that Audi's sportscar programme could have much more relevance to their road technology. Audi's first diesel sports-prototype dominated the Le Mans 24 Hours on its race debut last weekend.

"For Audi it was a unique chance to bring a diesel to Le Mans because Audi was the inventor of the direct injection system for road cars, and we pushed this technology in the last ten years to a very high level," Ullrich said.

"We sell in Europe more than 50% of our cars (as diesels) and I think in France it is even 74%.

"When the ACO gave us the chance with the new rules to run with different types of engine and different types of energy, and the diesel was allowed as well, we thought immediately that this opened new challenges to us.

"We would like to bring what our technicians develop on the road and bring it into racing and push it. It proves that motorsport can be supportive to road car technology and this is an important message for us.

"There was quite some load on our shoulders, because if this had not worked it would have difficult to promote it and we would have looked idiots. This was the risk and I am very proud that we don't look like idiots!"

Ullrich thanked race organisers the ACO for making their diesel programme possible.

"At Le Mans it is possible because the rules allow different kinds of engines," he said. "This is not something which is new, this is one important point of the history of Le Mans for many, many years and this is why many manufacturers have decided to come here.

"It is the only form of motorsport where you can prove what you think is the right technology. This is one of the strengths of the rules from the ACO and you can't take this and just put it in other rule books."

He was not sure if Audi's Le Mans success would be the catalyst for increased diesel usage elsewhere in international motorsport.

"There are some other forms of motorsport where you can run diesels," said Ullrich. "For example in the World Touring Car Championship you can run a diesel engine, it is just up to somebody to do it and nobody has yet."