Mercedes has brought its first substantial upgrade package for the W17 to Sakhir: redesigned sidepods now follow a different profile, the floor has been completely overhauled with modifications in the outer sections and in front of the rear wheels, and updates have also been introduced to the diffuser and mirror supports. An experimental diveplane was also tested.
After six days of testing where teams evaluated car reliability and made initial setup adjustments, the second and final session in Bahrain is likely the most significant. This is when teams not only refine setups but also begin introducing upgrades ahead of the championship.
Mercedes is among the teams introducing notable innovations, with extensive updates distributed across the car, including micro-aerodynamic solutions. The modifications, focused mainly on the sidepods and floor, indicate that the package seen today at Sakhir is substantial and enriched with experiments aimed at data collection.
Redesigned sidepods
The most noticeable change concerns the sidepods, which now have an entirely new profile in the central and rear sections, as seen around the Petronas sponsor area. The lines are now smoother and the rear section more tapered and streamlined, with a closure different from what was observed during the previous test.
With the outer profile of the sidepods changed, the “slide” design has also been revised to follow a different path. This is evident in images showing the white AMG lines along the bodywork, steeper towards the rear. The radiator inlets have also been modified, although less noticeably.
Revised floor and rear wheel area
The W17 upgrades do not stop there. Brackley engineers have also intervened on the floor. Immediately after the bargeboards, the “sidewalk” design has been completely reworked: it now features a more sculpted profile, closing at a right angle earlier than before.
The elements in front of the rear wheels have also been redesigned to fit the new aerodynamic package: they now include two longitudinal channels along the floor with a curved ending, replacing the horizontal cuts seen last week. Additionally, the final element has been entirely redesigned, without the 3D-printed components observed during the first test.
This is an extremely delicate area aerodynamically, and it is no surprise that Mercedes, like other teams, has focused considerable attention here. The goal is to manage turbulence from the rear wheels to prevent it from disrupting diffuser efficiency.
Mirror supports and diffuser refinements
Regarding the diffuser, this second test session saw the introduction of a particularly interesting small vertical appendage on the outer part, attached to the inner wall of the diffuser with a metal element. Together with the diffuser surface, it generates a small jet to control the exiting airflow.
Brackley engineers also refined the mirror supports, now shaped similarly to solutions already seen on Alpine and Ferrari cars. This allows the mirrors to function as genuine aerodynamic elements, maximizing the volumes allowed by the regulations.
In the central section of the car, the air intakes have also changed. Intermediate openings on the engine cover, introduced on day three last week, were closed today and replaced with a new opening located further forward on the sidepods. This demonstrates that Mercedes is also testing to identify the most effective configurations and evaluate their overall aerodynamic impact.
As in the previous two tests, wool threads were placed under the rear wing support to monitor airflow. The last noticeable update concerns the front wing, which remains largely unchanged from the first Sakhir test, except for one detail: the addition of a diveplane, a small appendage located on the outer endplate.
Interestingly, this was a simple experiment: the two diveplanes were not integrated into the wing structure but temporarily attached for data collection. One of the diveplanes even detached in the morning. Once testing was completed, Mercedes reverted to the standard configuration seen last week.
