Pit stop' are usually regulated by fuel and not tyres at Le Mans. There maybe a few laps more they can run, but I can,t see it doing more than 2 more laps than the R8, possibly only one, which was very economical for an endurance racer.
The engine stats
90 degree V angle
2 cams per cylinder head
4 valves per cylinder
Torque 1100 Nm +
Bhp 650 +
Fuel pressure 1800 Bar (26460 psi)
Boost 2.94 Bar (43.22 psi) with a 39.9 mm air restrictor
This engine has an all aluminium block for light weight. The power band is between 3000 to 5000 rpm. The biggest problem Audi had was making the tramsmission last with so much torque. The combustion chamber is in the piston and does not have it in the cylinder head like the car ran by Zytek last year.
The injection system inject's in 3 stages.
The first stage injects a microscopic amount well before TDC. As the piston nears TDC the main injection happens and combustion takes place. Then as the cylinder goes down the bore, and cylinder pressure drops off, another small amount of fuel is injected. It's this third phase that assists in producing the massive torque figures.
This last injection phase needs to be microscopic, as too much will create black smoke (unburned diesel) which is an instant black flag, and out of the race. This rule was brought in by the ACO to limit over fuelling.