Valtteri Bottas has shone after his switch to Mercedes and it was not lost on fans how the Finn was able to put pressure on his old team at last weekend’s Emilia Romagna Grand Prix.
The Finn’s charge was helped by a fairly significant upgrade at Alfa Romeo’s disposal for Imola, with a notable change in its sidepod philosophy evident as a result.
The changes on the C42 start at the front of the floor though, with the leading edge distribution of the floor and the strakes altered to improve not only how the airflow migrates under the car but also how it travels around the upper surface and around the sidepod .
Comparing the new sidepod solution with the old one, it’s obvious that the bodywork is now drawn down to meet with the floor, which will clearly have an impact on how the airflow not only travels around but also over the sidepod.
Alfa Romeo C42 floor tunnel detail
Fortuitously, Alfa Romeo’s livery helps with this distinction, as the red section at the rear of the sidepod illustrates the differences between the two configurations without need for any additional accompaniment.
It’s also worth noting how the undercut is retained for as long as possible before the floor and sidepod merge, granting room for the airflow as it makes its journey along the car’s flank.
Alfa Romeo C42 sidepod comparison
As can be seen from the top down overviews (inset) the new bodywork that merges with the floor doesn’t align completely with the upper surface of the sidepod to create the full width downwash ramps we’ve seen elsewhere.
However, it does likely improve the geometry of the floor if we consider how this corresponds when viewed from the underside.
Some modifications were also made to the rear brake duct fence, with the geometry of the forward section changed in order to open up the channel for which the inlet resides behind (red arrow).
