We touched on it in another thread, tire pressure etc and didn't go much further because of general opinion.
What particularly interests me in analysing this is the reason behind changing it from Pirelli.
Increase of pressure is specifically used to support the tire structure / carcass by reduction of flex under load it is predicted to experience.
To split initially and examine just the structure we must remove the tread area temporarily from considering it's influence.
As they've got a raised front only temperature (against general trend) then they are predicting a harder time from heat build than normal.
Theres other influence definitely, but primarily and major in that heat accumulation is the flexing of the structure by deforming, squashing, sqeezing etc and so by raising start pressure the structure simply flexes less under the projected load it is going to experience.
The risk is taking it over temperature such that it starts to fail in that structure, ultimately to "de-laminate" fall apart in layman's terms.
Also carries risk of tread gauge material literally becoming unbonded from the structure to give initially "blistering" or more substantial tread detachment.
Now the more interesting relationship with the tread. The flex comes from the tread being "located " effectively to the track ... grip in other words. This to cause the structure now to bend between vehicle mass (including aero load) how the tire holds the track.
I'll use the example of soft tire here, if the driver raises the tread temperature very fast, such that the structure temperature doesn't have decent chance to follow that "curve" in accumulation, then the tread can go over temperature and start reducing grip against track from sliding too much. At which point the ability to generate flex in the structure now goes down. The driver starts to feel understeer, the structure doesn't see enough flex to bring it into optimum, the they call that "graining " which makes them slower.
Just as LeClerc did in Las Vegas when Max caught him after roasting his tread but not having built heat in structure sufficient to let the WHOLE tire function within it's IDEAL temperature range.
The alternate approach is to bring them in slowly (notice that in MV&RB, also Ferrari chassis) then as the structure temp comes up to ideal AND the tread coincide, then the full performance can be extracted.
Raised pressure increases that gap POTENTIAL between getting them both to the same place, at the same time.
The car with the absolute greatest load will always have advantages in accumulation of tire structure flex (that MB chassis seems to do this) to switch on tires (also valuable at low temp, but not exclusively) and demonstrates better performance with less risk.
Some circuit and pressure combination clearly favour just this raised pressure, for some chassis.
Conversely, high track heat and ambient temperature may take both the structure and the surface too high and out of range.
The problem the driver faces here, in a sprint, is that there will be precious little room to work their own characteristics of car tire interaction while even holding their position. Its he'll for leather from the start. That also leaves naff all room for any sort a strategy.
Get any graining and you'll be "toasted" by those near you, with little options in practical terms. There's very little in the way of respite to let the fronts recover around the lap , then try to give it absolutely everything in it out of last corner so you don't get caught by DRS down that straight.
It's gonna be hectic for all.
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