turbo engines and the fuel-efficiency of smaller, lighter cars. A minimum weight of 800 kg was put in to maintain structural safety and there were defined dimensions of 100 cm minimum height, maximum 200 cm width and 480 cm length. These dimensions mirrored those of the ACO's GTP regulations. There was also a compulsory 100x80 cm flat floor area required between the axles to try to limit the undertray "ground-effects" performance enhancements. Fuel tanks were a maximum of 100 litres capacity and no more than 25 fuel stops were allowed in the race for each car – a maximum of 2600 litres from the start. The windscreen regulations were such that the drag effect would almost guarantee that any car would need to have a closed-bodyshell and not open-top. Unlike other races in the championship run to a set distance, where teams could calculate their required fuel economy, the open-ended nature of Le Mans would require prudent fuel management. Going on the previous year's winning run by Jacky Ickx and Derek Bell of 4825 km (just under 3000 miles) using this year's maximum 2600 litres of fuel would require a fuel economy of 54 litres per 100 km. This was at odds with the IMSA regulations, that instead used a sliding weight-scale to balance engine capacity. This then precluded the Daytona and Sebring endurance rounds from the World Championship. With Group C taking over, it made the Group 6 and Le Mans GTP classes redundant. Group B would supersede the Group 4 and Group 5 GT classes. Entries Whereas other races in the World Championship needed their fields bolstered by Group 6 cars “grandfathered” into the entry list, the Le Mans list had very strong support for the new Group C with 33 entries, coming from a wide variety of manufacturers and racing specialists. There were factory teams from Porsche, Ford, Lancia and Mazda; with racecar builders Lola, March and Rondeau bringing works cars. Finally a raft of small privateer specialists brought their own Group C designs. These amounted to 30 "works" entries, the most seen at Le Mans for many years. However, as an interim year, to complete the field the ACO accepted entries from IMSA in the GTX and GTO categories, and had limited spaces for the former FIA classes. Note: The first number is the number of arrivals, the second the number who started. Group C After