The fuel-flow regulations for the opening three rounds of the 2014 World Endurance Championship have been adjusted in favour of the petrol-powered LMP1 machinery.
The Toyota TS040 HYBRID and the Porsche 919 Hybrid have been granted more energy per lap and larger fuel tanks in the final Equivalence of Technology table published by rulemakers the FIA and the Automobile Club de l'Ouest ahead of the WEC opener at Silverstone on April 20.
The table also shows a reduction in the amount of energy, measured in megajoules per lap, allowed to the turbodiesel Audi R18 e-tron quattro, as well as a smaller-capacity fuel tank.
Toyota and Porsche, which both run in the 6MJ hybrid sub-class, will now be allowed 139.5MJ per lap of the 8.47-mile Le Mans circuit rather than the original 137.5MJ in the original regulations published in December.
The fuel capacity of the TS040 and the 919 has been raised from 66.9 to 68.3 litres.
The fuel allocation for the Audi, which runs in the 2MJ hybrid class, has been adjusted downwards from 140.2 to 138.7MJ and the fuel capacity of the R18 reduced from 54.8 to 54.3 litres.
The new table also includes the energy allocation and fuel-flow rates allowed for Silverstone and round two at Spa, which is in direct proportion to the length of those circuits relative to Le Mans and then multiplied by a factor of 1.11.
The changes follow the supply of information to the FIA and the ACO by the three LMP1 manufacturers based on their testing up to the end of March.
The manufacturers were given a fuel table on the eve of the official WEC test at Paul Ricard March 28-29, but the FIA and the ACO refused to make it public at that stage.
The published table is dated April 7, although it is unknown if there have been any changes since the test.
The aim of the rules to guarantee technical equivalence between the different technologies used in LMP1.
The fuel rules for LMP1 are now set in stone up to and including the Le Mans 24 Hours in June, after which they will be re-evaluated and locked in place for a full calendar year until after the 2015 24 Hours.
Cars that exceed their energy allocation, which is measured by the same Gill sensor used in Formula 1, are subject to a sliding scale of penalties.
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