Despite the Emilia Romagna Grand Prix weekend being a special one due to the Sprint format, which meant drivers only had one practice session before qualifying on Friday, an array of developments were introduced up and down the grid.
Red Bull were particularly busy, as they brought a significant upgrade for Max Verstappen and Sergio Perez, with a focus on the underside of the car.
It was effectively a double evolution for the team, as the RB18 not only went on a diet, but also took on various aerodynamic changes.
In terms of aerodynamics, developments were focused on the area under the chassis where the airflow is split.
A double splitter - with an additional fin - has been applied (see above), bearing similarities to Ferrari's F1-75 and the Aston Martin AMR22.
The aim is to increase the efficiency of the Venturi channels at the bottom of the car. An invisible change has been made here, but their construction is now lighter.
According to talk in the Imola paddock, the new and improved Red Bull is around four kilograms lighter. Compared to the first winter test, it is believed to have lost some 15kg.
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