Red Bull has continued its efforts to claw back performance versus McLaren with a revised Formula 1 floor design for this weekend’s Miami Grand Prix.
Although the RB21 has shown glimmers of competitiveness over the opening five rounds, the car's weaknesses have largely manifested in its handling characteristics and greater tyre degradation versus the MCL39.
In an effort to improve its baseline performance, Red Bull has made a series of detailed changes to the underbody of its 2025 F1 car to extract more performance and improve its stability.
The fences inside of the floor's opening have been repositioned, and the team has stated in its pre-event technical notes that this should "extract a small increase in load for the same flow stability".
Further optimisation of the floor has extended to its floor edge wing, which now features greater camber (ie. wing curvature) to extract more downforce in this area.
Neither McLaren nor Ferrari have registered any changes for Miami, having done so at the previous rounds in Saudi Arabia and Bahrain respectively.
Ferrari used a new floor at both Middle Eastern races, while McLaren's diffuser modifications were only seen in practice at Jeddah.
Mercedes has brought a new rear wing assembly to Miami, which features a lower-camber upper rear wing flap to trim downforce - and hence drag - out of the package in an effort to improve the W16's top speed along the two DRS zones.
Although Miami has a mix of corners, the long straights (or acceleration zones) between Turn 8 and Turn 11, and later between Turns 16 and 17, requires the teams to pare back the downforce to maximise their top speed.
As such, Aston Martin has also introduced a new wing package to address both the front and rear of the car; it has a new front wing with "less aggressive profiles" to trim some of the load out of the car to balance it with the changes to the rear wing.
This also extends to the beam wing, which "works in conjunction with the upper wing for this event to achieve the required drag range".
Williams also has a shorter-chord beam wing to cut drag out of this weekend's package.
Elsewhere, Alpine had prepared new front brake ducts and front suspension members to improve the flow in this area and increase the brake cooling efficiency, but has elected not to run them this weekend owing to the nature of the sprint weekend.
Sauber has also modified its lower front suspension wishbone fairings to help pursue its aerodynamic improvements.
