The Automobile Club de l’Ouest (ACO) together with the FIA World Endurance Championship has decided to bring changes in its Equivalence of Technology rules ahead of the 6 Hours of Silverstone race.

Following the gap seen during the 6 Hours of Spa and Le Mans 24 Hours between the hybrid Toyota LMP1 cars and the non-hybrids of Rebellion, DragonSpeed, SMP Racing and ByKolles, the ACO and WEC have been forced to alter its EoT rules.

On the lines of the feedback received after the Le Mans race, the ACO has decided to eliminate the 0.25 percent laptime advantage for Toyota from next month’s 6 Hours of Silverstone round – the percentage was worth half a second per lap for Toyota.

This resulted in the Japanese manufacturer winning by a massive 12 laps advantage over the privateers during the Le Mans 24 Hours race. The fuel flow for the non-hybrid cars has been increased to 115kg/h from 108kg/h compared to 80kg/h for Toyota.

The fuel flow of the refueling system has also been altered for the private teams with the cars having normally aspirated engines given 15kg weight break – all the changes has been made to help the privateers to reach to the performance levels of Toyota.

ACO’s Techinal Delegate Thierry Bouvet said: “As a result of the studies carried out this winter we gave private teams a fuel flow to help them achieve performance levels close to those of the hybrid cars.

“We then took advantage of concrete information collected during the Prologue, the first round at Spa and the Le Mans test day. As competitors know, not everything can be foreseen at Le Mans.

“For example, between the test day and qualifying at Le Mans the fastest time in the LMP2 category improved by 2.4 seconds compared to 0.2 seconds for the non-hybrid LMP1s. Several factors can explain this such as different track conditions or because the teams didn’t want to compromise reliability.

“Finally, multiple contextual parameters could also have affected certain EoT estimations. This is why we’re taking the following decisions: the performance gap of 0.25% is being reduced to 0% (the 0.5-seconds difference per lap at Le Mans between hybrids and non hybrids is no longer relevant).

“The fuel flow for privateer LMP1s goes up from 108 kg/h to 115 kg/h compared to 80 kg/h for the hybrids. Furthermore, the fuel flow of the refuelling system used by private teams has been increased. And last but not least, cars powered by normally-aspirated engine will benefit from a 15kg weight reduction.”