Tech F1i: Red Bull leads F1 teams' upgrades for Japanese GP

Red Bull has implemented at Suzuka its first significant upgrade package of the 2025 season, with the Milton Keynes-based outfit tweaking three specific components on its RB21.

In addition to Red Bull, four other teams – Haas, RB, Williams and Sauber – are running modified cars this weekend in Japan.

Red Bull’s changes aim to instill more stability into a car that even Max Verstappen has found difficult to master, with the Dutchman never really in the running for the win in Australia and China, two races dominated by McLaren.

According to the FIA’s official documents, Red Bull’s changes involve the central exit aspect ratio of the RB21’s engine cover as well an enlarged exit duct with blanking options, while a "mild revision" has been made to the car’s the lower wishbone shroud and fairing into the rear wheel bodywork.

Red Bull describes the respective changes as helping reduce the losses incurred by the upper and lower rear wings for optimising cooling; improving local flow conditions with attendant fairing into the brake duct assembly.

"So you have a central exit. Well, everybody's got a central exit, haven't they, and supplemented with louvres at the sides if we want,” further elaboratedBull chief engineer Paul Monaghan

"So the air that comes out of there, the flow that comes off the top body mixes with the flow coming through the top body, so it tumbles and merges a bit and obviously it's not as clean as you might want it to be. Just downstream of that is the rear wing. So, if we get it right, then the cooling exit is of least impact to the rear wing performance, be that upper or lower.

"It comes out under the main wing, doesn't it, on top of the beam wing. So if you're trying to hold a low pressure on the bottom of the beam wing, you're then feeding it with something else.

"So if you get your downwash right, it goes through the gap, and there's no bother to it. So we're just trying to make a small refinement to enhance that a little bit. That's all.

"We've been able to do it with a little expense, and we've had the time to bring it here, so we'll bring it here.

"It gives you a small cooling improvement; it means we can run the car more closed and do less harm to the rear wing. So it's a small win. Let's take it."

Over at Haas, the US outfit previewed the introduction of a revised floor on the team’s VF-25 in a bid to solve the car’s instability in high-speed corners.

Describing how the update works, Haas said:

“This geometry changes the floor volume in floor proximity, aiming to improve stability when the car is running at low ride-heights in high speed corners.”

Williams has introduced a new front wing flap and endplate with a re-profiled edge on its FW47 to improve local load and flow conditioning.

The updated front flap geometry produces more local load, which allows for a more efficient rebalancing of the load from the rear wing.

The interaction of the subsequent flow with the front suspension and brake duct furniture is different, which leads to improved control of the front wheel wake.

Working in conjunction with the new flap, the revisions to the endplate modify the flow leaving the front wing assembly and improve its interaction with the downstream aero devices.

Sauber’s modification on its C45 include the car’s floor body, rear wing and beam wing, with the changes aiming to improve flow quality all along the floor, increase overall efficiency and improved cleanliness of the rear wing assembly.

Finally, as far as RB is concerned, only a small change has been implemented on the team’s VCARB02, specifically a reprofiled Halo shroud to improve the flow quality downstream of the safety element.

Keep up to date with all the F1 news via X and Facebook