McLaren’s start to the 2026 Formula 1 season has already been forgettable. Beyond the race results, the most interesting aspect of the British car is its wheelbase: the MCL40 has the shortest wheelbase on the grid, 35 cm shorter than the 2025 car and a full 15 cm less than the Ferrari SF-26. This was a deliberate and bold decision by the team led by Andrea Stella, achieved through meticulous work on the rear axle, not to mention a complete redesign of the sidepod cooling system.
F1 2026: technical challenges linked to weight regulations
It is equally striking to analyze a car with a design parameter so far from its competitors: a drastically shortened wheelbase. The FIA’s regulatory overhaul for 2026 mandated a sharp cut in wheelbase, from 360 cm down to 340 cm. The move has been widely praised by both drivers and fans.
Alongside the smaller dimensions, the floor aerodynamics have been completely overhauled, significantly reducing ground effect. In the era of the “wing cars,” teams were forced to maximize the full 360 cm length to extend the Venturi tunnels. For 2026 cars, this requirement has disappeared.
Now, the area responsible for generating downforce from the floor is considerably narrower and standardized across all teams. Another challenge imposed by the FIA concerns minimum weight, lowered by 30 kg. While logical given the smaller cars, this has made the engineers’ job more difficult than ever.
FIA tightens roll-bar tests for 2026
Today’s power units add roughly 34 kg, coupled with ongoing safety developments, including stricter roll-bar load tests and a new two-phase frontal crash test, increasing mass further. Overall, the cars are effectively 64 kg heavier.
Hitting the minimum weight target has become a true ordeal, with a 10 kg excess potentially costing 0.2 to 0.4 seconds per lap, depending on the track. In this context, the overall car length becomes a crucial variable during design to trim unnecessary kilos.
It’s also why we are now seeing cars with radically different solutions, innovative approaches across multiple areas, and varied wheelbase dimensions. Relying on official renders alone is insufficient, as these are often digitally altered before release.
McLaren: the shortest car on the 2026 grid
Between the Bahrain and Australia races, using precise photography and with the collaboration of Camillo Morande (who has historically assisted with my 3D animations), we carried out a direct comparison among the top teams. The 3D analysis confirmed initial visual impressions from the closed-door Barcelona testing. McLaren’s MCL40 emerges as the shortest car on the grid.
Until 2024, such analyses were conducted during the Hungarian Grand Prix, an opportunity now lost due to the track redevelopment which removed the press box and the famous terrace above the FIA technical area. This terrace was a “secret” spot, ideal for perfectly aligned photos of cars on the scales.
The real surprise comes from the McLaren: the MCL40’s wheelbase is approximately 15 cm shorter than the regulatory 340 cm. Andrea Stella and Rob Marshall confirmed this measurement directly. The reduction was achieved by moving the rear axle forward without changing the distance between the front axle and the cockpit (or the start of the sidepods), keeping it aligned with competitors.
This can be clearly seen when compared with the Ferrari SF-26. The adjustment is critical to separate front wheel turbulence from the sidepod inlet, optimizing both aerodynamic efficiency and cooling. The 15 cm reduction was made possible by compacting the gearbox-housing assembly.
All-new cooling system for the MCL40
Within this context, Rob Marshall’s team had to redesign the entire cooling system, as well as the aerodynamic surfaces of the sidepods and engine cover. In theory, this should provide benefits on all circuit types. The placement of the heat exchanger above the power unit remained almost unchanged, but the sidepod radiators were drastically repositioned. They now appear long and narrow, surpassing the size of those on any other car, with a much shallower installation angle compared to the more compact, shorter radiators on the previous MCL39.
Consequently, the geometry of the sidepods and the heat extraction concept have also changed. On the MCL39, there were tiny lateral vents on the engine cover with a narrow central outlet. For 2026, the MCL40 features a fully sealed side cover, with a larger central outlet at the rear.
McLaren’s season began worse than expected, so to evaluate the true potential of this shortened wheelbase, it is first necessary to solve the Mercedes power unit issues. Similarly, optimization of the aerodynamics will be crucial. Updates are expected in Japan, as Andrea Stella confirmed in China. It will be interesting to see whether the team has learned from early setbacks and if the aerodynamic revisions will deliver a significant performance step for the MCL40.
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