Parc Fermé
VerifiedThe rules locking a car's setup once qualifying starts, preventing changes that would undo the qualifying result's fairness.
From the moment a car leaves the pits for qualifying until the race's formation lap, it's under parc fermé conditions: the FIA restricts what teams can change on it, to stop a team qualifying with one setup and racing with a substantially different, better one.
Only a short list of adjustments are allowed under parc fermé, things like tyre changes, minor front wing angle tweaks, and repairs for safety reasons; anything beyond that requires special permission, and usually comes with a grid penalty attached.
A team that wants a bigger setup change (say, after a wet qualifying leaves the car set up wrong for a dry race) has to choose: keep the qualifying position and live with the setup, or start from the pit lane instead in exchange for a free setup change.