2025 car comparison thread

[Farnborough]

Interesting perspective there.

That McL showing most evolved application of the available pieces there.

That top rear link being very empathetic and analogous to "conditioning " vane on approach to leading edge of floor structure.
Interesting words coming from McL (believe from Stella) about driver feedback and feel being "numb" which is in accordance with predicted relationship in using more extreme geometry on front suspension/steering, thus to ultimately favour or prioritise aero function.

Last race results hinted at dominance of pull rod type arrangement in competency of aero performance with a lockout of top four positions too. Ferrari now creeping into this sphere as they come to more familiarity of the system they've built.

[AR3-GP]

McLaren have found a way to control these vertical kicks and the downforce they generate across various ride heights. This is the big tricky topic, as massive kick surface can generate massive downforce peak that disappears if the kick stalls locally - while also leading to high-speed bouncing that Ferrari struggled with.

I believe this floor design is part of the reason McLaren exhibits lower Top Speed figures, both with and without DRS, compared to rest of Top 4 cars.

Further on this point, I talked a lot about how so much "energy" is being consumed by the Mclaren and it was not clear where it comes from. Maybe it's lost to the tire cooling solution.

I've been saying it for a while.

An insider speculates: "Perhaps they circulate the air in such a way that it stays cool in the crucial areas and shield the heat through the use of certain materials." Chief Technical Officer Rob Marshall is said to be the father of the system. He has been carrying the concept around with him for years, but has only now made it work. That would be bitter for Red Bull. Marshall was at Red Bull for 17 years before moving to McLaren in early 2024.

Stella also made an interesting statement. "Even when it gets hot, our car stays cool. We've developed a very efficient cooling system." This also affects tire temperatures. If the car as a whole gets too hot, it radiates to the tires. Stella's statement also explains why the McLaren is near the back in terms of top speed. More cooling reduces efficiency.

https://www.auto-motor-und-sport.de/for ... peraturen/

[Vanja #66]

cooling tyres through secret suspension arm channels, they are surprisingly open about it

[Luscion]

Apparently the FIA took a look at Mclaren's brake duct solution after the miami gp and determined it complies with the regulations

https://www.the-race.com/formula-1/mcla ... all-clear/

[AR3-GP]

cooling tyres through secret suspension arm channels, they are surprisingly open about it

I can't rule it out at this time

[FittingMechanics]

While I find the phase change materials an interesting idea, shouldn't it affect their ability to switch on the tires quickly? For example starting behind a safety car or after pitstops. Other cars could make the drum hotter than McLaren and thus fire them up quicker. We don't seem to observe these warmup issues.

Obviously phase change material could allow for the drum to absorb more heat while staying at the same temperature, that would help long term modulation of the drum/rim temperature which fits with the observed effects.

To me, it sounds more like they have some kind of a clever system for cooling, perhaps the system doesn't work at low/medium speeds due to aero not being there (like you would have in warmup laps), but with higher speeds it feeds the system much more and super cools the rim? It would fit better with the alleged DRS top speed deficit McLaren seems to have.

Very fascinating. Btw, given that Toto is fully on board with McLaren being legal maybe Mercedes has an idea how the system works and are bringing their own version in the future.

[Alexf1]

Apparently the FIA took a look at Mclaren's brake duct solution after the miami gp and determined it complies with the regulations

https://www.the-race.com/formula-1/mcla ... all-clear/

Can you show me the quote from the FIA where they say that?

[Vanja #66]

I can't rule it out at this time

"Very efficient cooling system" "Our car stays cold"

I wonder what exactly on chassis gets hot and radiates internal heat around front axle. Driver feet heater?

[Emag]

An insider speculates: "Perhaps they circulate the air in such a way that it stays cool in the crucial areas and shield the heat through the use of certain materials." Chief Technical Officer Rob Marshall is said to be the father of the system. He has been carrying the concept around with him for years, but has only now made it work. That would be bitter for Red Bull. Marshall was at Red Bull for 17 years before moving to McLaren in early 2024.

Stella also made an interesting statement. "Even when it gets hot, our car stays cool. We've developed a very efficient cooling system." This also affects tire temperatures. If the car as a whole gets too hot, it radiates to the tires. Stella's statement also explains why the McLaren is near the back in terms of top speed. More cooling reduces efficiency.

https://www.auto-motor-und-sport.de/for ... peraturen/

Wait, this is actually kind of mad. Why would he give this information away?

It sounds like they have some sort of overly aggressive cooling solution that would normally keep the tires too cold, but they use residual heat from PU components and transfer it to the rear tires (somehow) to counteract that.

The front-end is relatively normal I would say, there's not much you can do about it there, but the rear must be really complicated. That's the area they try to hide during assembly right?

[Farnborough]

An insider speculates: "Perhaps they circulate the air in such a way that it stays cool in the crucial areas and shield the heat through the use of certain materials." Chief Technical Officer Rob Marshall is said to be the father of the system. He has been carrying the concept around with him for years, but has only now made it work. That would be bitter for Red Bull. Marshall was at Red Bull for 17 years before moving to McLaren in early 2024.

Stella also made an interesting statement. "Even when it gets hot, our car stays cool. We've developed a very efficient cooling system." This also affects tire temperatures. If the car as a whole gets too hot, it radiates to the tires. Stella's statement also explains why the McLaren is near the back in terms of top speed. More cooling reduces efficiency.

https://www.auto-motor-und-sport.de/for ... peraturen/

Wait, this is actually kind of mad. Why would he give this information away?

It sounds like they have some sort of overly aggressive cooling solution that would normally keep the tires too cold, but they use residual heat from PU components and transfer it to the rear tires (somehow) to counteract that.

The front-end is relatively normal I would say, there's not much you can do about it there, but the rear must be really complicated. That's the area they try to hide during assembly right?

The highlighted statement could be read to mean two (opposed) view.

1) that the car emmiting too much heat will cause the tires to heat by radiatnt pathway, so efficient is the cooling system though, that this eventuality is avoided.
2) that they transfer heat from core operating systems to provide heat into the tire by some means.

I think it's the first statement in #1 above.

[Farnborough]

In looking at these effects it's often productive to go with a "phase change " (pun intended ) in the thinking you approach them with.

Another way of "removing" heat from rear brakes could be to run effectively too high on regeneration in braking the rear axle, to then push excess capacity (keeping within the recovery remit) to resistance energy to heat exchange facility, then to cool that output through cooling capacity.

That would relocate the kinetic output to a more manageable location and allow liquid cooling of that as product.

Back down of regeneration potential in BBW system for Q laps (they do anyway, switching regeneration off for that single lap) would effectively move the heat "location" around the car to best effect.

Run race with higher regeneration in place while bleeding off excess through resistance/cooling exchange and away from rims.

It will give "differential" braking on rear axle too (rear retard operating through "open" diff setting) on corner entry, requiring different driver approach to that phase !!! a characteristic we've seen and commented about by both drivers.

[Emag]

In looking at these effects it's often productive to go with a "phase change " (pun intended ) in the thinking you approach them with.

Another way of "removing" heat from rear brakes could be to run effectively too high on regeneration in braking the rear axle, to then push excess capacity (keeping within the recovery remit) to resistance energy to heat exchange facility, then to cool that output through cooling capacity.

That would relocate the kinetic output to a more manageable location and allow liquid cooling of that as product.

Back down of regeneration potential in BBW system for Q laps (they do anyway, switching regeneration off for that single lap) would effectively move the heat "location" around the car to best effect.

Run race with higher regeneration in place while bleeding off excess through resistance/cooling exchange and away from rims.

It will give "differential" braking on rear axle too (rear retard operating through "open" diff setting) on corner entry, requiring different driver approach to that phase !!! a characteristic we've seen and commented about by both drivers.

They would have had all of these tools available since early hybrid era though (unless I am missunderstanding). It’s at the very least a consideration I would say and it wouldn’t be an easily missable oversight, contradicting the apparent confusion of other teams on how McLaren is managing such impeaccable temp management.

[Farnborough]

As I understand it the BBW (brake by wire) used so far has the initial brake application through regeneration for the rear, then as the allowed store capacity in the rules for recovery is reached, the BBW system blends in line pressure to rear calipers .... supposedly in seamless "tapering" such as to be invisible to driver input.

They could have the POSSIBLE addition to dump out through electrical resistance and produce heat instead of filling energy store. This then to be cooled by supplementary system to evacuate. Technically, it wouldn't breach the energy stored allowance as it's wasted. This I don't recall as part of original design.

It would fall straight into that thesis area of the linked yt clip in terms of handling heat transfer at different location from the wheel assembly though.

Effectively it would add inefficiency to the car, which is easier than chasing efficiency. But would likely have a drag penalty for the additional cooling.

It could have the "toggle" effect observers are theorising in how it's deployed though.

Some "theatre" in operation of car build to obscure the real reason by getting people to look at the brake tins a bit of fun to complete the illusion.

[GrizzleBoy]

Another way to think about what he said is that he meant the complete opposite of the words he said and they're actually re-routing heat to turn the tyres on how and when they want to allow them to properly maximise the life of the compound.

[AR3-GP]