Toyota tweaks hypercar to run different tyre sizes for 2022 WEC

The Japanese manufacturer's four-wheel-drive GR010 Hybrid ran with 14-inch tyres front and rear in its title-winning debut season in 2021, but will switch to a second option currently allowed within the rules for this year.

That means it will run 13.5-inch front and 15-inch rear Michelins, the same as the rear-drive Glickenhaus 007 LMH.

The move has yet to be confirmed by Toyota, but sources confirm that pre-season testing has taken place with the car in the revised configuration.

A Toyota spokesman would not confirm the switch and said that it would be revealing the technical specification of the latest GR010 ahead of the official WEC prologue test the weekend ahead of the Sebring 1000 Miles season-opener on May 18.

Toyota's switch between the two tyre-size options in the regulations has been influenced by rule changes following the completion of the process of convergence between the LMH category and sister LMDh class, which comes on stream next year.

The so-called '120 rule', the minimum speed in kilometres per hour at which power can be deployed at the front wheels by an LMH hybrid when the cars are on slicks, has become part of the system of Balance of Performance.

This means that this speed and the 150km/h minimum enforced last year when the cars were on wet-weather tyres can change from track to track and from car to car.

It followed concerns from the manufacturers particularly those building cars to the rear-drive only LMDh rules about the advantages offered by all-wheel-drive.

It is unclear at this stage whether the change in the tyre configuration of the Toyota will count as one of the five evolutions allowed on performance grounds, known as 'evo jokers' in the regulations, to each manufacturer over the life cycle of an LMH.

Manufacturers must apply for permission to make the evolutions to the FIA and Automobile Club de l'Ouest, which write the rules.

An evo joker covers one area of the car as defined by the homologation form.

Peugeot has confirmed that its 9X8 is running 14-inch tyres front and rear and is confident that a fair balance between cars running the different sizes will be maintained in the BoP.

The latest rules say that for LMH cars homologated after 2022 the 13.5/15-inch set-up will be mandatory.

Spy shots of the 2022 Toyota reveal bigger rear wing endplates, though it is unclear if these are the extent of the aerodynamic evolutions for 2022.