McLaren looking to make the cut
Besides the ‘T’ wing mentioned earlier, McLaren briefly tested a slightly revised rear wing last Saturday, though the British team elected against running it after it did not yield tangible benefits.
McLaren also brought a new floor to Shanghai, characterised by a meter-long longitudinal slit. Basically, this serves to isolate the air flowing under the car so the diffuser can work more efficiently. A similar opening can be found on the Mercedes, Ferrari, Toro Rosso, and Red Bull, albeit in a different shape for the latter.
The rationale is the same as the floor slots ahead of the rear wheels, i.e to allow high-pressure air above the floor to go under the car in order to seal the edges of the diffuser.
How does it work? The encounter between low-pressure and high-pressure air generates a vortex that acts as a wall to protect the diffuser from the dirty wake of the rotating rear tyres.
Sealing the diffuser’s edges is all the more important this year with teams running higher rake angle on their 2017-spec cars, which is especially true of the McLaren-Honda MCL32.
