ACO are ready to screw the diesel cars by a regulation change concerning tank capicity. It's Ironic though - Pug are bulding a diesel car as well, and the ACO usually do what they can to favour the French teams.
IMSA and ACO are still working on these new regulations. They won't let any further details out before Septemper.

Le Mans plans diesel restrictions

http://newsimg.bbc.co.uk/media/images/41782000/jpg/_41782020_audi_getty203.jpg
Le Mans 24-hour race organisers are planning curbs on diesel engines after Audi's crushing win this year.
Audi made history with the first-ever diesel-powered Le Mans victory at the famous French circuit last month.
But questions have been raised over the equivalency formula used to keep different engine types equal.
The Automobile Club de l'Ouest claimed Audi had bettered their closest rivals by 3.2 seconds a lap and said it will "take steps to reduce its performance".
Peugeot plan to join Audi in racing a diesel at Le Mans next year.
But one of the key advantages of the technology - improved fuel efficiency - will be curbed.
The Automobile Club added: "The fuel tank capacity will have to be adjusted in such a way that the cars receive the same quantity of energy at each refuelling stop.
"This will mean a smaller tank for those cars which are equipped with a diesel engine." Audi drivers Frank Biela, Marco Werner and Emanuele Pirro won Le Mans last month by four laps from their nearest petrol-engined rivals.

Well the same thing happened after the victory of the Mazda 787B and the rotary engines, the new ragulations made the rotary engines less competitives than the regular ones.

I think this is stupid, this is stopping inovation in the sport.
If they had let diesels have as much fuel as petrol engines it would make the other teams inovate more to remain compeditive and make the race more intrasting.

Whats next, a limited battery size for the hybrids.

They haven't confirmed the details yet. Maybe they will just end up using smaller restrictors, higher minimum weight, lower turbo boost or smaller fuel flow restrictors. It's all in order to equalize the performance between diesel and petrol engines.

So once again diversification is cut off, an important part of motorsport is experimentation but the governing bodies seem to be cutting off every vaguely significant improvement. Instead of slowing the Audi's down the rest of the field should catch up.

So once again diversification is cut off, an important part of motorsport is experimentation but the governing bodies seem to be cutting off every vaguely significant improvement. Instead of slowing the Audi's down the rest of the field should catch up.
Thats exactly my point.
What is it about European organisations and governing bodys that make stupid descions like these. (No offense to any europeans here)

Issued Friday 7/14:

Tooele, Utah – IMSA today published a bulletin that affects the refueling rig restrictor of the diesel cars participating in the American Le Mans Series, specifically the Audi R10 TDI cars. The change limits the refueling restrictor from the current 38mm permitted under the regulations to 33mm, effective immediately.

"As was highlighted in today's press bulletin issued by the ACO, there is an overall desire by the organizing bodies to work toward a situation where all cars, no matter what fuel they choose to use, have the same amount of energy on board," said Tim Mayer, Chief Operating Officer of IMSA. "However, that is not the situation with the current regulations. So as an interim step, we have restricted the R10 so that it cannot receive more energy in the tank in a given time frame.

"We notified the team of this change at the Lime Rock Park event. However, because of a variety of test and calculation methods that are possible to determine the energy content of fuels, we chose to hold the public release of the bulletin until we had verification of the numbers," added Mayer.

The current regulations permit the same 90-liter tank on both diesel and gasoline cars but permit the larger restrictor on the refueling rig of diesel cars because of the different viscosities of the fuel.

"The original intent was to permit the full volume of the tanks to be filled in the same time," said Mayer. "However, diesel is a more energy-rich fuel for any given volume. The change that we have implemented means that the energy delivered will be similar, for the diesel versus gasoline, for the same length of refueling. The goal is to ensure that competitors have the opportunity to compete without a quirk in the physics of the fuels creating a particular advantage. We are currently working with the ACO to come up with a formula for tank sizes for a variety of different fuels."

So if they have to have smaller fuel tanks then they will have to add weight to make up what they lost in the fuel's weight, right?

I don't know if that made sense.:/

No..., it means that diesel fuel has more energy/volume than gasoline. You have to suck oil through a smaller straw than with gas.

i think they would be complete losers to limit the size of the gas tank for diesels. just because Audi came out with something great and beat everyone in Le Mans, doesn't mean they now have to slow them down so everyone else can catch up. i think it's up to the other teams to come up with something to compete with Audi, not having these dumb racing regulations.

I count 2 that can't read/comprehend...

That is dumb. They are biased to petrol cars. You would think that Top Gear organise lemans with that sort of ignorance.

Audi will have to kill the guys in charge.... so they can continue to use the R10 with a full tank. But since Peugot wants to use a diesel they probably won't limit the tank capacity.