The Italian company has already decided that its other tyres will remain unchanged for next year, and the Mexican running is the only opportunity to prove the worth of the revised C4.
Pirelli undertook a similar test with a new C2 on the Friday of the Japanese Grand Prix weekend last month but decided that it didn’t represent any improvement.
The decision to carry over unchanged tyres from one season to the next is an unusual one, and previously only happened between 2020 and 2021, when COVID meant there was no tyre testing.
Typically Pirelli has to keep up with increasing downforce levels, and in essence, make a judgement on where loads will be by the final race of the 2024 season.
However this year the focus of its in-season testing was on running without blankets, a move that has now been postponed to 2025 at the earliest.
Therefore it decided to stick with the current product, and the construction first introduced at Silverstone, which was itself a by-product of the no-blanket testing. However, the option to tweak the C4 compound remains open should Friday’s test be successful.
"In Mexico, we have a C4 with the idea to have a tyre the same performance as the current C4, but a wider working range and a bit better mechanical assistance,” Pirelli F1 boss Mario Isola explained.
“With the C4, at some circuits, we had a bit of graining, so we want to reduce it. If the test is successful, the plan is to introduce the C4 for next year. Otherwise, we keep the one we have now."
If Pirelli decides to switch to the new C4, examples will have to be fast-tracked for the end-of-season Abu Dhabi tyre test. Even if the tyres stay the same for 2024, that test will still be useful for Pirelli as teams will add additional sensors to gather data.
Isola remains confident that the current construction will be able to deal with the load increase to the end of 2024, pending new simulation data.
“If I look at the simulations we received in June, with the current construction we can cope with this level of load,” he said.
“But this year, for example, they have been able to achieve a higher level of performance or downforce compared to simulations earlier in the year."
"We are going to receive new simulations at the beginning of December, and obviously we will analyse them because they are probably more accurate compared to what we had in June."
Following the introduction of a no-blanket wet in Monaco, Pirelli still has the opportunity to test and introduce revised wets and intermediates during 2024.
"The target is to have a wet tyre with a better performance in order to have a better crossover with the intermediate, and possibly an intermediate that is working without blankets, already for 2024," Isola said.
“Probably not from the beginning of the season, because with the calendar we have next year the first tyres have to be delivered quite early for Japan, China, and Australia, so we don't have the possibility to change it from the beginning of the season.
“But if we find a better tyre for 2024, we will discuss with the teams, the FIA and F1 the opportunity to introduce those tyres during the season."
Meanwhile, Pirelli is continuing its investigation into its Qatar Grand Prix tyre issues, which has not yielded any firm answers yet.
"It's a bit early for any conclusion, because some of the tests are taking a bit of time to do properly, and then we will prepare a report," Isola explained.
"We are now testing several tyres with different tests to understand the level of the damage,” said Isola. “Looking at the microscopic analysis, we can confirm that after the race we had some damage in line with the sprint.
“We had also the possibility to run some specific tests to understand the residual life based on a normal circuit, not a circuit with the kerbs.
"The tyres had some residual life in them when tested. That means that the 18-lap distance was the right decision, in my opinion, because it was taking into consideration a margin of safety. It was exactly what we wanted to see.”
