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With 22 circuits, there can be a lot to take in, so we’ve organised for you to join us in Lando and Oscar’s engineering briefings, where we’ll walk you through this weekend’s key trackside topics so that you can enjoy the Mexico City Grand Prix to its fullest.

The Autódromo Hermanos Rodríguez is a unique circuit, with so much of the conversation centering around altitude, instead of the actual track. At 2,285 metres above sea level, the circuit is the highest point of the calendar, and that comes with some significant implications for the team, who have to contend with a quarter less oxygen as well as all of the impact it has on the car.

Those include less power, downforce and grip, and a greater demand on the turbo and cooling systems. There’s also some additional chatter about the plank this weekend, as well as a Pirelli tyre test to tackle. Tom Stallard will be leading this weekend’s briefing, in partnership with Google Chrome, where he’ll look to explain all of this and more.

It’s time to begin. Grab a coffee and follow us through the glass doors and into the Paddock Performance Centre. Take notes if you need them, but please keep them to yourself. 

Engineer: Tom Stallard 
Event: Mexico City Grand Prix 
Circuit: Autódromo Hermanos Rodríguez 

Why does everyone keep talking about high altitude?  

The Autódromo Hermanos Rodríguez is an outlier circuit. It’s dominated by having one big, long straight and by the altitude and the impact that has on downforce. It’s the lowest downforce circuit of the year – less than Monza – even though you’re running as much downforce as you’ve got in the aero package. With high altitude comes low air density which means cooling is a nightmare. Lots of teams will be bringing bigger brake ducts, potentially more open bodywork. Everybody will be running with open shoulder louvres. There’s no air to pull through the ducts, so everything has to be massive to keep the cars cool.  

We’ll split the cars on cooling specification at the start of FP1. We would like to know if we have any headroom – because more cooling means more drag, and so anything we can do to reduce that adds performance.  

When we first came back to Mexico, everyone was keen to do a lot of following practice – because following another car closely really can push cooling to the limit – but we’ve all got pretty good references now, and understand what sort of allowances we need to make for following – but we’ll still want to do a few laps in dirty air.  

What aerodynamic specification will we be using? 

We’re going to be running the rear wing we had in Austin and Qatar. It isn’t quite our ultimate highest downforce rear wing but it is a little more efficient than the one that is, because it has less drag, so it’s become part of our default maximum downforce package now. 

Some of the work we do will be looking ahead to 2024 

There is nothing new on the car this weekend, other than some tweaks for cooling. Of course, the last two races have been Sprint weekends, which has limited our practice running – but at this stage of the season we’re not feeling this has put us on the backfoot. We’ve got a pretty good understanding of the upgrade introduced in Singapore – but there’s still some validation tests to do here, and because everything seems to fit in with our models, much of this work is tasked with looking ahead to 2024.

Tyre choice  

Tyres are interesting this weekend, as we’re going softer a step in the Pirelli range. Whether or not the C5 is a good race tyre, or whether it’s going to suffer with graining is something we’re keen to discover. We think it’s going to be OK, but it’s something we need to learn.  

The Autódromo Hermanos Rodríguez has low tyre wear – because the load into the tyre is low – but tyre surface temperatures can be a problem because the track surface gets very hot. This, again, is a consequence of altitude. The sun is more direct, which really warms up the asphalt. Last week in Austin, track temps didn’t get above 43°C. Here, they may go above 60°C, even if the air temperature is a little cooler than Texas.  

Why there is less grip  

It's also the case that the thin air makes the cars slide around a little more, and those two things combine to create problems with surface temperature management. It’ll be one of the things we’ll want to practice with Oscar, knowing how he’s going to fight other cars while managing surface temperatures. The good thing, because it’s not a Sprint, is that we’ll have opportunity across practice to figure that stuff out.  

We’ll also do some learning for qualifying. The lap is pretty much flat-out – but you don’t want to over-push. Surface temperature control means you can’t slide the car around – not that you ever really want to do that in an F1 car. It’s a question of driving normally, rather than driving to save the tyre – but with an awareness that being too aggressive at the start of the lap will cost you some time at the end.  

Judging that will require some figuring out. As will knowing if this is a first lap tyre, if it requires a warm-up lap, as sometimes happens on the shorter circuits, or if it’s one that is better on a second push lap after a cooldown lap. We’ll investigate these things in practice – but usually, they’re not too difficult to see.  

Does the Pirelli tyre test benefit us?  

We’ve also got a Pirelli tyre test. The rules are the same as they were for the test in Japan – albeit with an experimental C4 compound rather than an experimental C2. We get two sets of test tyres and are free to do what we can with them, rather than having a pre-determined run plan from Pirelli. It’s essentially a compound test for next year. We might use this in 2024 – or stick with the one we have.  

Does the tyre test benefit our programme this weekend? That’s a matter of perspective. It’s not useful from the point of view of studying tyres – because you’re not learning anything about the real compounds you’ll qualify and race on – but it does present you with an extra opportunity to learn about your car. You can use these to experiment with kerbs, for instance, but not to gather information on race strategy. That makes them handy first-up, when the grip is low, and useful for another run before your quali sim.  

A fascination with the plank  

Everyone seems very interested in the plank this week! The Autódromo Hermanos Rodríguez isn’t particularly bumpy, and because there’s no air, you can run the car very low, without having to run it too stiff – because there’s less downforce to then squash it into the ground. This lets you run a softer car that will ride the kerbs well. There are kerbs to run here – but they’re not particularly aggressive.  

What can be challenging here is that, on the softest, grippiest tyres, the lack of downforce means the inside wheels are very unloaded, which causes ride problems mid-corner. The double-apex T6 is the first place, but the hairpin in the stadium can be bad too. It can also be set off if you take too much kerb elsewhere – T2 for instance. So, it’s tyres and air density rather than bumps that’ll cause problems this week – but it’s something we’ll study intently through practice.  

Confidence counts  

While we’re learning all about this, the drivers will also be learning about the track for themselves. This is a circuit where driver confidence counts for a lot, and that only builds up with laps on the board. There isn’t much rear end in the cars here, which means the rear is very unsettled. Positioning the cars accurately with an unsettled rear relies on good confidence from the driver – fortunately both our drivers are pretty good at that, so I think they’ll do well – but they will need to build the confidence. Surface temperature and low grip puts the consequences of mistakes quite high.  

Briefing complete. Time for Lando and Oscar to head out onto the track and put our hard work to the test.