The timeframe of the rules, which make up the respective Hypercar and GTP classes in the two series, has been extended for reasons of stability, according to both the WEC and IMSA.
Richard Mille, president of the FIA Endurance Commission, told Autosport: “Stability is very important. It is the reason why we have all these manufacturers in Hypercar, that and the reasonable costs involved.
“We want to avoid obsoleting the cars: we need stability but at the same time flexibility, which is why we have the system of evo jokers so that manufacturers can evolve their cars.”
IMSA boss John Doonan said: “This is important for the manufacturers involved from a stability point of view, but it also creates opportunities for manufacturers looking at potentially coming into the GTP class.”
LMH rules came on stream in the WEC in 2021 with a five-year lifecycle, which was extended by two years when the LMDh cars arrived in 2023.
The move was announced at the traditional pre-Le Mans 24 Hours press conference held by WEC co-organiser the Automobile Club de l’Ouest.
The ACO and the FIA gave further details in the timeline for the introduction of hydrogen-fuelled cars into the Hypercar category.
The rules will be in place to allow a manufacturer to go for overall victory at Le Mans by 2028 when the two bodies are expecting the arrival of the first entrants with the zero-emissions fuel.
The existing LMP2 formula will also be extended for a further year until the end of 2027, the ACO has confirmed.
ACO president Pierre Fillon said: LMP2 is a key category for the ACO and we must absolutely protect it.
“We talked to all the teams and it was agreed to extend the category until the end of 2027,” he said.
Fillon regularly talks of a pyramid of endurance in which LMP2 plays an important part, even with its disappearance from the full WEC this year.
It remains the top category in the European and Asian Le Mans Series and is also an important component of the prototype grid in IMSA.
The current cars will be replaced by a new breed in 2028 that will have a downsized engine and will be lighter.
A one-year extension means that the current regulations will have had an 11-year lifecycle.
The rules, which demand the use of the one-make 4.2-litre Gibson V8 engine, were introduced ahead of 2017, initially with a four-year span.
There were a series of extensions, the latest of which was confirmed last October when it was announced that Gibson Technologies would continue as the engine provider at a new introduction date for the next-generation of P2 car in 2026.
LMP2 has become a de facto one-make category for the ORECA 07 chassis as rival chassis developed by Dallara, Ligier and Riley/Multimatic proved unable to match its performance.
