Dissecting the MCL35M - And Why McLaren are Already on the Back Foot
We all know the livery is the same, but the car has many significant talking points
I sat there at seven in the evening, working on my F1 Fantasy team (yes, I am a spreadsheet person) and listening to a boring car launch, agonisingly waiting for the car to be revealed. Thirty minutes of waffle later, they showed us... the same thing!
At least that's what it looks like on the outside.
The biggest change - although not so obvious - is the engine. Switching engine supplier at all isn't easy but going from Renault to Mercedes, who go about the fundamentals of engine configuration in different ways, is even harder. Renault have their compressor and turbine in the same section, whilst Mercedes opt for a split design, with the compressor on one end and the turbine on the other.
Therefore not only do McLaren have to compensate for this by repackaging the aforementioned parts, but they also must reconfigure the electricals, wiring, cooling and so on as well.
As part of cost-saving measures, for the new season teams are permitted three 'development tokens' with which they can make changes to the car. McLaren have already used at least one of these on the rear of the chassis to accommodate the Mercedes PU, and so have less to use for outright aerodynamic gain.
This could be detrimental later in the season, because their rivals who have not had to use tokens on repackaging a new engine will be able to make more performance tweaks, and therefore gain laptime.
The rear axle moved back ever so slightly, whilst the body itself was slimmed. This brings drag advantages as well as more space for aerodynamic exploitation. Because of the new engine arrangement, the intercooler is also repositioned meaning the radiator inlet is reshaped and the sidepod is more undercut.
If you look at all of the Mercedes powered cars (Aston Martin, Williams and... Mercedes, obviously) they all have this undercut sidepod area. This draws air from the top side of the car and channels it to the diffuser, therefore increasing downforce.
The biggest change for 2021 is the revised floor; all of the lateral slots along the side which had huge benefits are gone (the red circle). The change was made to reduce downforce by 10%, and more importantly reduce loads on the rear wheels to stop them for delaminating (remember Silverstone?).
Each team will have their own way of going about it, but McLaren seem to have not done very much. James Alisson said in their raw form the rule changes would see Mercedes from comfortably first, to comfortably last.
There's a tiny slit towards the rear tyre (the small red line) which may try to drag air underneath and sucked towards the diffuser, but - from the launch car itself - there isn't much else adapted.
As part of the new cooling, the MCL35M (M for Mercedes) has these new gills positioned behind the cockpit. From here we can also see that the mirror is a bit different, perhaps in the hope that it will create vortices (strong, high energy spiralling air) that will be dragged to the diffuser area.
Here you can get a better view of how the sidepods differ between the last two seasons.
The endplate is also ever so slightly altered; the lower slots - red lines - remain the same, McLaren have had these for a few years now. But the upper slots have been removed, and in their place are some vane-like pieces which were pioneered in 2019 by... Haas, strangely enough!
In 2020 Red Bull also used them at high downforce tracks:
See?
Furthermore, they've changed the front crash structure to a more Mercedes-orientated design - in place of the conventual jutting iteration you can see above. This was narrowed to make space for the 'cape' which allows you to start redirecting airflow to the bargeboard earlier. They previously ran the slotted vanes that are slowly growing out of fashion.
Here's the 2021 spec. See what I mean?
At first they'd tested this in Mugello, last year, in order to implement it on the car before the token system came into force - presumably to save some for the engine mounting. After some teething issues, they ran it for the rest of the year and actually it helped them quite a bit - McLaren of course claimed third in the constructors.
Here is a better look at the endplate:
They've been quite secretive here, in that where they would usually have the diffuser McLaren have just removed it from the render. For 2021 the internal fences have been reduced by 50mm and again this was to reduce downforce. Yet again, each team will go about reacting to this in a different way and for some reason they've decided to hide their way of doing it!
Aaaaand... that's about it! Not too much to conclude with the new car, basically just some aero bits are different and they've had to spend vital tokens on reconfiguring the new engine. Hope you enjoyed this!
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All pictures are source from the above-stated sources. All edits except those marked with an * are my own
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