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McLaren #MCL35M technical thread: The 2021 McLaren is probably the ‘new’ car with the most mechanical similarity to the 2020 spec car. This is because McLaren has change power unit supplier from Renault to Mercedes. #F1 1/many
The Mercedes PU is a different shape to the Renault with a split turbo layout with the compressor at the front of the V6 block and the turbine at the rear. Renault has the complete turbo at the rear of the block. 2/
This means that McLaren had to modify the rear bulkhead if the MCL35 tub to accommodate the Mercedes V6 (and its battery pack), it also needed to change the gearbox case. This meant it had no development tokens to spend. /3
This means the inboard suspension and most mechanical components carry over from 2020, but the electronics are new, there is revised cooling and some minor engine installation differences. /4
Aerodynamic development is not restricted however though the Mercedes style nose shape carries over from late 2020 as the front impact structure (the nose essentially) is a homologated part - 20 & 21 parts for comparison here. /5
Power unit installation changes and aerodynamic freedom has allowed for a revised roll hoop ducting layout. It looks like the roll structure remains unchanged but the shrouding is different. Suggests revised cooling layout. (20 & 21 compared) / 6
McLaren is sometimes understandably a bit coy about its new parts, the new bargeboard layout looks to me to be more 'launch spec' than final. Was a big area of development last year - 20 spec compared to 21 below. Keep an eye on this area for more development /7
Of course the most talked about change for '21 is the rear floor - this can be seen comparing the #MCL35 with the #MCL35M - James Key said earlier that it has significantly cut rear downforce and suggested that it had not all been recovered yet. /8
McLaren is being understandably cagey about the rear end of the car - it will feature a new diffuser with shorter strakes, but @Mclaren don't want us to look too closely at it right now, covered or edited out in the launch pics. /9
My mate @ScarbsTech has pointed out the reduced size of the rear brake winglets - a 2021 reg, I'd expect a fair few developments here. https://twitter.com/ScarbsTech/status/1361400103374884867 /10
The upper wishbone pickup extension of the upright seems to be slightly different, but as this is part of the upright but it is a homologated part. McLaren may have changed this last year and I didn't notice! (20 & 21 compared) /11
The sidepod inlet shape has carried over but the could be some different blanking in the ducts (hard to say comparing launch images - ( #MCL35M lighter image) /12
Thats all for now so here are some more #MCL35M pictures. I'll update this thread a bit in testing - but you'll have to look at @F1 TV & @autosportbooks for more detail.
