paddock behind the garages was also re-organized with more facilities added for spectators, including more shops, new landscaping, and the Audi Tower monument. The public roads from the Indianapolis corner to the Porsche Curves were re-surfaced. Run-off areas at the Dunlop Chicane, Tertre Rouge, Indianapolis, and Ford Chicanes were also partially asphalted in order to avoid gravel being brought back onto the circuit by cars which had gone off course. This also increased safety by allowing the cars to slow themselves more efficiently using their brakes and tyres on tarmac. Regulation changes Rule changes were announced by the ACO for all Le Mans-based series such as the American Le Mans Series, the Le Mans Series, and Japan Le Mans Challenge effective in 2007 for all four classes in October 2006 following close coordination with engineers, fuel companies and manufacturers. Diesel engined LMP1 cars had their fuel tank capacity decreased from to and with petrol engines retained their tanks. LMP2, GT1, and GT2 class vehicles had to be fitted with 5 per cent smaller air restrictors than they had run in 2006, in order to decrease power. Each of the GT1 and GT2 classes were allowed to run ethanol and other alternative fuels if approved by the ACO. The ACO also imposed Le Mans specific rule changes. All entries had to run Shell fuel in either diesel or petrol form. The temperature inside closed-cockpit cars was not to exceed in cars with air conditioning or above the ambient air temperature in cars without. The ACO would monitor cockpit temperature, and stop any car in which those limits were exceeded. Noise level regulation was revised: the noise emitted from the car had to be less than 113 dB with measurement taken at from the edge of the track. Newer but not older LMP900 and LMP675 class prototypes were allowed to be entered for the event. It was also decided to begin the event at 3:00 pm local time, one hour earlier than the normal 4:00 pm, to provide French spectators more time to vote in the 17 June French legislative election. Entries The ACO's Selection Committee received 76 race entry applications by the 24 January deadline. It reviewed every application and granted 55 invitations to the 24 Hours of Le Mans with entries divided between the LMP1, LMP2, LMGT1 and LMGT2 categories. Automatic invitations Automatic entries were earned by teams which won