Peugeot 9X8 - 10/12: Why is it the only Hypercar with 31" tires?

What do the regulations say?

Unlike the LMDh, the 4WD Le Mans Hypercars can opt for two different types of tire. Either 31" wide tyres at the front and rear, or 29" at the front and 34 at the rear. But the article 12.3.3 of the LMH technical regulation has been modified a few weeks ago. The governing bodies prefer that all the cars eligible in Hypercar have similar tires, and all the LMH homologated after 2022 December 31 will have to take the 29'' / 34'', like the LMDh and the non-hybrid LMH. But this does not concern Peugeot, as its car is currently undergoing homologation in order to be the start of the 6 Hours of Monza, the fourth round of the WEC, on July 10.

Why keeping this concept?

Toyota is having trouble with its rear tires in 2021, and has decided to abandon the 31", as we explained HERE. Ferrari has also changed its mind. But what about Peugeot? "Our car is designed for 31x31 and we would have had to change a lot of things, and that would have had an impact on our weight distribution and aero balance," replied Stellantis Motorsport director Jean-Marc Finot. "The impact on our schedule and budget would have been too big to consider a change." 

"When the discussions started in the summer of 2021, we evaluated the possibilities we had," added Technical Director Olivier Jansonnie. "And our project was very advanced around these tires. The car was almost finished. We knew that our weight distribution would be within the window recommended by Michelin, and we had a lot of discussions with their engineers and came to the conclusion that it was preferable to run the 9X8 with these tires given its weight distribution (close to 50-50). Our car was designed around a certain weight distribution concept. We could have changed the car, by swinging it more to the rear, but it was clearly not the right solution." In other words, it would have challenged the whole concept of the car.

Is it still worth having four-wheel drive?

In view of the increase in the speed of the electric motor triggering connected to the front axle, the question deserves to be asked. As a reminder, since the beginning of the current season, Toyota can only use its hybrid system above 190 km/h, compared to 120 km/h last year. "For those who decided to go with a four-wheel drive concept, it's a bit frustrating," Olivier Jansonnie told us. "Even though the simulations carried out before Sebring showed that with the tires we have on the Peugeot, we would have benefited from a slightly lower hybrid system activation speed." And therefore different from the Toyota.

"But it is certain that if the hybrid system's triggering speed is raised to such high levels for a long time, the fact of having developped an electric engine would be quite frustrating, knowing how demanding it is from human and economic points of view," admits Jean-Marc Finot. "And that's not to mention the additional parts (for the transmission) and therefore the risk in terms of reliability. If we don't get an advantage, it loses all its meaning."

Peugeot will therefore have its own tires, unlike its rivals, all of whom are equipped with the same 29" / 34" tires. An advantage or a disadvantage? "Worried or not worried, we don't have a choice, so we'll deal with it," admits Jean-Marc Finot. "We have been very good at complying with the regulations, respecting the spirit of the regulations completely, with a full Peugeot Sport design hypercar. This should not penalize us." Especially as because of the BoP, the difference between the competitors will be based on the management of the tires and therefore their consistency during a stint.

On the same topic :

- 1/12 : Behind the scenes of the tests in Magny-Cours

- 2/12 : Interview with Jean-Marc Finot

- 3/12: Objective Monza!

- 4/12 : Jean-Eric Vergne (1/2): "There is plenty of room for improvement"

- 5/12 - Jean-Eric Vergne (2/2): "Winning Le Mans with this insane car"

- 6/12 : Will the 9X8 be homologated without a rear wing?

- 7/12 - Loïc Duval: "I feel at home in Endurance racing"

- 8/12 : Who are the key people of the team?

- 9/12 Loïc Duval: "At the wheel, it remains a prototype"