They were agreed between rule makers the FIA and the Automobile Club de l’Ouest and the manufacturers on Wednesday afternoon ahead of the start of practice on Thursday for this weekend’s Spa round of the championship.
The move follows the #7 Toyota GR010 HYBRID losing 11 minutes in the pits early in the second hour of the Portimao WEC round earlier this month when a rear driveshaft torque sensor mandated in the regulations stopped working.
Toyota had to pit the car and replace a rear corner in Portugal despite a request to race control to continue running.
It is understood that two stints’ worth of data needed to have been gathered before such a request was agreed under the previous protocols.
That is why Peugeot was able to continue running the #94 9X8 that finished fifth at Portimao; it suffered a failure of a driveshaft torque sensor during the second half of the race.
New protocols have now been agreed to allow a car to run in default or back-up mode if there is a repeat failure early in the race.
Toyota Gazoo Racing Europe technical director Pascal Vasselon revealed that these procedures would be in place for the Spa 6 Hours, round three of the 2023 WEC, on Saturday.
“We very quickly agreed with the FIA and ACO that we have do everything possible to make sure we avoid stopping a car when such a thing happens,” explained Vasselon.
“We have had a very constructive meeting on how the procedures could improve to make sure we make the best use of the data available to allow running in default mode.”
The driveshaft torque sensors are a key component of the Hypercar formula because they measure the power output and the energy used over a stint, which are both laid down in the Balance of Performance for each car running in Hypercar.
The sensors on the front driveshafts of the four-wheel-drive Le Mans Hypercars, which race against the new rear-drive LMDhs in the top class of the WEC, also police the ban on the torque control that would be possible with a hybrid system on the forward axle.
Vasselon would not go into details, but he revealed that the back-up would involve the sensor that measures power on the input shaft of the gearbox.
“We have one redundancy, which is the input shaft of the gearbox, so we have the output of the engine,” he explained.
“The commitment is to make best use of the data available.”
Vasselon explained that it was important that running in default mode offered no performance advantage.
“The idea is to define a default mode that cannot be a performance gain,” he said.
“We have to make sure that with all these controls the default allows the car to run but certainly without any performance gain.”
He revealed that the performance of a car running in default mode would “somehow have to be downgraded but not much”.
The Peugeot shared by Loic Duval, Gustavo Menezes and Nico Muller was slowed as the team strived to keep it within the prescribed torque curve and its per-stint energy allowance laid down by the BoP.
Peugeot Sport technical director Olivier Jansonnie revealed that “we had to detune the car quite a lot to keep it legal” as a result of the failure at Portimao.
He stressed that the onus was on the teams to ensure that a car running in default mode remains within the parameters laid down by the BoP.
“We have to develop our own solutions to back up the sensors when they fail,” he said.
“Part of the work that can be done on our side is to make sure that from what we learn on our virtual sensors we can run the car in the maximum performance conditions when it happens, which was not the case in Portimao.”
It is unclear if the failures on the Toyota and the Peugeot two weeks ago were linked.
Jansonnie revealed the series was still awaiting answers from the manufacturer.
Neither Toyota nor Peugeot revealed the identity of the maker of the sensors, but it is known to be California-based MagCanica, which has publicised its involvement in the WEC.
The failures at Portimao were the first to occur during a race weekend in the WEC since LMH machinery arrived in the series in 2021, but Vasselon revealed that there had been issues during testing.
