LMP1 rule changes for 2018 delayed to control costs

The move delays changes planned for 2018 to both the hybrid and the chassis regulations.

The scope of the hybrid rules would have allowed for an additional or third energy-retrieval system at the same time as introducing a new 10 megajoule hybrid sub-class above the existing 8MJ top division.

The changes to the chassis rules focused on the survival cell and the seating position of the driver.

The decision, which follows Audi's withdrawal from the WEC announced last month, resulted from a meeting of the rule-making strategy committee that incorporates representatives from rule makers the Automobile Club de l'Ouest and the FIA, and remaining manufacturers Porsche and Toyota.

ACO sporting director Vincent Beaumesnil told Autosport: "We keep pushing on the costs and this will have a big effect by maintaining the existing rules rather than taking another step.

"We always listen to the manufacturers currently involved and those that are looking for an opportunity to join.

"This was a tough decision but a sensible one that makes sense in the current context."

The decision to delay the new rules follows a series of cost-cutting measures introduced over the past two seasons, which include limitations on testing, the number of engines used each season, hours spent in the wind tunnel and personnel working at each race.

Changes to the aero rules for next year that will rob the factory cars of downforce remain in place.

The move needs to be ratified by the next meeting of the FIA's World Motor Sport Council at the start of December.