Ferrari SF-25 development continues: major updates expected after Spanish technical directive. Ferrari remains committed to the SF-25, with a major upgrade package planned after the Spanish technical directive.

The final developments of the so-called Venturi cars are in the works. All teams will only be able to afford one major design revision package, as opposed to the two steps of previous years. Even the corrections are limited, which is why McLaren has “its finger on the trigger,” but in practice, the team led by Andrea Stella continues with a cautious approach. The late technical directive regarding the wing flexibility, at least according to some, also carries weight. All front wings will need to be rebuilt with new specifications, which has a financial impact. At the beginning of the 2025 Formula 1 championship, Ferrari team principal Frederic Vasseur already announced that the Maranello team’s introduction of the technical directive would not alter their plans; rather it simply set the date for the introduction of the new front wing, which had already been in development.

Normally, factories must provide a minimum of 6 to 8 units per team, with appropriate load variants and stock to deal with frequent back-to-back races. We can estimate the cost at about $1 million. The average development budget for current cars is approximately $18 million, which would mean a good 10% of the budget would, according to Red Bull, have been spent unnecessarily due to the delay of the flexing technical directive. However, since this is the final year with this philosophy, there is a double concept to dedicate tools and resources to. This means a worse impact in terms of percentage, probably close to double.

So what happens if the values change in Spain? Less flexibility of the wings limits the aerodynamic balance of the cars, and the usage window may shift because the fast corners will become more decisive to manage compared to the slow sections. The cars may suffer more understeer in the medium-slow corners to keep the wing lower in the fast ones.

In the first five races of the 2025 Formula 1 championship, Max Verstappen limited the damage, staying relatively close to the McLaren MCL39 cars of Oscar Piastri and Lando Norris. At the 6.174-kilometre Jeddah Corniche Circuit, the penalty gave the victory to the ice cold Australian driver. From their perspective, the stewards applied the rules, questionable but not scandalous. It should also be noted that the escape routes allow for a certain approach, and Oscar Piastri could have pushed Max Verstappen, as the Dutchman had done in the past. Notably, Kimi Antonelli locked up the front and then gave the position back to Charles Leclerc, who had given him more space than Oscar Piastri.

Red Bull is pushing with a new aerodynamic update package which should be ready for the Imola Grand Prix. It is expected to be worth two tenths theoretically, but no one trusts the correlation. Engineer Gianpiero Lambiase, between Bahrain and Saudi Arabia, as Max Verstappen’s trusted man, unusually returned to Milton Keynes to personally contribute to some technical discussions, revealing a profile very similar to Ross Brawn.

For Ferrari, some small adjustments are scheduled for the upcoming race. A significant aerodynamic update package will be deployed later, possibly across multiple events, but a revised rear end could come after the introduction of the technical directive in the Spanish Grand Prix weekend. The technical leadership of the Italian side wants to show that the SF-25 project is not a failure and that things can change. The SF-25 can indeed do more and have a say in this Formula 1 championship. Charles Leclerc can now drive the car much better, and more speed in fresh air to avoid degradation requires a better performance in the qualifying session.

The Saudi Arabian Grand Prix once again showed that turbulence has returned to the levels from 2021, and now chasing cars need about one second per lap better pace in order to be able to overtake. The large diffusers extract the most air but are no longer as responsible for the downforce as they were three years ago. The engineers’ attempt to achieve more downforce without lowering the car has silently focused work around the bodywork and the edges of these floors, which now generate more harmful interactions for the car behind.

Side-by-side comparative images of the best cars are perhaps the most interesting example to at least grasp what is meant by flow cleanliness and search for efficiency in downforce. All teams had concluded that the downwash design left greater pathways, but the stability of downforce was the most complex part to find. Aerodynamicists work in the wind tunnel, but the correlation is problematic because vortices under the floor are unstable at high speeds. If the car sways, so will the vortices around the body, throwing technicians into a crisis. No antidote has been found as the search for more downforce moves the reference points each time. No observer can fully understand the reasons behind a design, but the visible differences are clear, as explained by F1 expert Giuliano Duchessa for autoracer.it.

The Mercedes W16 has the cleanest horizontal line, though it still maintains very wide and steep edge slots. The low line is well integrated with a generally flat design of the front wing, which is why it appears to have a low drag coefficient. McLaren and Red Bull seem the most harmonious, but the MCL39 has reached the best compromise for a year now, limiting the use of cuts in areas of greater flexing of the floor, which reduces the rigidity of the floor. Unlike Ferrari and Red Bull, the surface of the large outer side panel behind the front wheel is below the maximum allowed, showing that the ultra-aggressive design of the front suspension can contain disturbances better than the competition. Mercedes might have optimized that area well too, at least in terms of numbers.

Ferrari has kept a layout not so different from the old car, at least in this area. There is a less gradual and more abrupt drop of the airflow under the sidepods. This could be one of the reasons causing problems when the SF-25 single-seater travels in dirty air. However, there is compensation from greater efficiency in the upper bodywork. In summary, rigidity and efficiency are always the key words of this regulatory cycle.

The Maranello team relies on Charles Leclerc to remain as close as possible to the top, while Lewis Hamilton is clearly in crisis. It is no secret that the multiple-time English champion could not digest the ground effect cars. He had very problematic Mercedes cars, not to mention the initial failure of the W13, and now a Ferrari that is deeply different from his routine, with which he has been driving since the end of January. This is not enough to explain his poor form, as other drivers have changed teams, and during the SF-23 TPC tests, he seemed to do well.

In Jeddah, Lewis Hamilton lost 5 tenths per lap to his Maranello teammate with some signs of inconsistency. Driving style says something but not everything; both want a responsive front end for corner entry, but Charles Leclerc adapts much better through the center of the corner. The Englishman needs to “feel the load” that pushes the car down, which requires very high sensitivity, and he is formidable in acceleration because it allows for strong tire management under traction. Unfortunately, with these cars, it is not possible to generate mechanical movement that fully aligns with his old preferences. Charles Leclerc, like Max Verstappen, has the most instinctive ability on the grid, even when the rear end is not planted.

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