The fastest car usually belongs to the team that develops it best over a season. Since 2021, F1 has rationed the two biggest inputs to that development: money and aerodynamic testing.
The cost cap
Each team may spend up to a fixed limit a year on the car, under the cost cap. Driver salaries, the three highest-paid staff and marketing sit outside it. For 2026 the cap rose from $135 million to $215 million, because almost nothing could be carried over to the new cars. Power unit makers have a separate cap of their own.
Aerodynamic testing restrictions
Wind-tunnel and simulation time is allocated on a sliding scale: the lower a team finished in the previous Constructors’ Championship, the more aerodynamic testing it may do. The champion gets the least. It is a deliberate handicap that helps the field converge.
Upgrades
Teams bring new parts through the season - a revised floor here, a new wing there. Whether an upgrade works is one of the season’s big stories: a team can gain three tenths in a weekend, or bring a package that takes months to understand. With the cap, a failed upgrade is money that cannot be spent again.
Why rules resets shake things up
When the rules change as much as they did for 2026, every team starts from a blank sheet. The order can flip, and the team that reads the new rules best can dominate early - until the others catch up through the season.