McLaren focuses on rear aerodynamics with diffuser update, avoids driver favoritism | Saudi GP. McLaren debuts a new diffuser and rear-end updates in Jeddah.

The McLaren seen in Jeddah features some updates. A new diffuser debuts on the MCL39, paired with modifications to the aerodynamics of the rear wheel assemblies, an area already worked on in the past month. The Woking-based team thus confirms its focus on the aerodynamic development of the rear end, whose traction effectiveness is already one of the project’s strengths. However, the team is careful to avoid any unequal treatment between Lando Norris and Oscar Piastri, adopting a more balanced approach than in past years.

The updates in Jeddah
The most significant change concerns the diffuser, aiming to intensify the extraction of airflow from under the car to generate more aerodynamic downforce from the floor, while also paying attention to sensitivity at various ride heights. Alongside this comes a second update to the appendages of the rear wheel assemblies, surfaces that generate aerodynamic load directly on the unsprung mass, without the filtering effect of the suspension. McLaren had already made changes in this same area at the Japanese Grand Prix two weeks ago, highlighting the attention paid to rear-end aerodynamic development.

The wheel assembly components represent a particularly sensitive area, as they interact aerodynamically with the diffuser. These elements, for instance, help mitigate the harmful impact of turbulence generated in the contact area between tire and asphalt, while also enhancing local low pressure to feed airflow extraction through the diffuser. McLaren is thus placing strong focus on rear-end development, making further updates in this area likely in upcoming races.

No favoritism
According to The Race, on Friday McLaren tested the updates only on Oscar Piastri’s car, before evaluating whether to use them on both cars for qualifying, though the outcome of this decision is not currently known. In any case, this was not favoritism toward the Australian driver, but rather a simple comparative test between the two versions.

Team Principal Andrea Stella has been clear about the intention to ensure equal treatment for both drivers. In 2023 and 2024, it sometimes happened that development packages debuted on only one car, as they were quite invasive and required a comparison with the old spec to better understand how to adjust the suspension setup for optimal use. However, in a season where both Lando Norris and Oscar Piastri are fighting for the title, McLaren is determined to change its approach and preserve harmony within the team garage.