For Formula 1 cars racing in Mexico City, the normal rules don’t apply.
When speeding down a straight that is almost a mile long, teams would usually need to race a car with as sleek a body shape as possible to cut through the air and hit top speeds quickly. But at the Autódromo Hermanos Rodríguez, where this weekend’s Mexico City Grand Prix will be held, it’s the opposite.
Autódromo Hermanos Rodríguez first held a Formula 1 world championship race in 1963. For the drivers, the track will feel more akin to racing on a slippery street course like the one in Monaco, where regular automobiles that use the streets when Formula 1 is not in town wear away the traction provided by the sticky tire rubber laid down by racecars.
In Mexico, it’s all about altitude. The country’s capital city is a little more than 7,000 feet above sea level, one of the highest of any capital city (La Paz, Bolivia, is No. 1 at about 12,000 feet). But in Formula 1 terms, there is no competition.
The next highest races are the Brazilian Grand Prix at about 2,700 feet above sea level and the Austrian event at about 2,200 feet. Las Vegas is next up at about 2,000 feet. Of the other 20 events this year, 11 sit under 50 feet.
Whereas the air is heavier at sea level, Mexico City’s great height results in thinner air, taking the breath away from drivers, suffocating cars and upending the normal engineering processes for the teams at the race.
“Theoretically you should be moving faster. But without that mass of air [to press down on the cars], it’s the same,” Tim Wright, a former race engineer for the McLaren team, said about the effects of Mexico City’s thinner air.
“They’re just moving through the air a lot differently than they would at sea level,” Wright added.
To compensate for this, teams attach their largest bodywork kits, like wings, to their cars. On tracks at or near sea level, these kits are usually required only if the track has many turns and few straightaways because the bigger wings, which increase downforce and thus traction, help cars turn faster in corners. On straights, that added downforce creates drag, which hinders acceleration. In essence, drag is good in corners; bad in straights.
But, Wright said, thin air means “you’ve just not got so much pressure on the wings,” which lessens downforce and drag. So to race in Mexico City, teams fit bigger wings to increase these aerodynamic effects and help drivers maintain speed in the track’s 17 corners. The cars still reach high speeds on straights that wouldn’t be possible using these bigger wings at sea level.
But even then, the altitude challenge means the drivers will still struggle to race their cars as they do elsewhere.
“Aerodynamically, it’s huge; it’s like driving in the wet,” the driver Lance Stroll of Aston Martin said. “It’s a huge reduction in grip. A very unique challenge, for sure.”
This means the cars move more erratically in corners.
“It’s quite a tricky track to drive,” said Santiago Ramos, a Formula 3 driver who is an official ambassador for the Mexico City Grand Prix.
“Whenever downforce reduces, it increases the risk of having a problem in the middle of the corner,” he added.
If this occurs, Ramos said the temperature of the tires would suddenly rise, and a driver would “lose grip in the next corner and the next braking zone” and be more likely to make a mistake and run off the track.
“It’s usually quite a crazy race in terms of crashing and everything because of that,” Ramos said.
The thin air also creates other big problems. The turbo hybrid engines that power the cars “rely on forced air” volume moving through them to stay cool, Wright said. This usually stops cars from overheating and breaking. But at altitude, “the thinner the air is the less cooling you’re going to have,” he said.
“The turbo in the engine gets much hotter than in other tracks because it’s working harder to try to compensate for that lack of oxygen,” Ramos said. “Cooling for the engines — the system of radiators — is working less because there is less mass hitting them, too.”
Wright said that Formula 1 engine designs with “a thicker intercooler to cool the air and a bigger compressor to force it into the engine” would do better in Mexico. For years, the Honda engine that the Red Bull and Visa Cash App RB teams used had a power advantage because of that. However, Mercedes in particular has improved its engine operations at altitude by altering its design to force in air.
To try to improve engine cooling in Mexico, teams will open gaps in bodywork pieces that are usually closed for races at sea level. They will also fit their biggest brake-cooling devices, as thin air causes drivers to struggle to quickly slow their cars because of brakes overheating.
Ramos said that teams could alter the software settings on the engine so that it would not work as hard and get as hot. But, Ramos said, “with the brakes, you cannot do anything because you still have to brake, and the brakes will still stress when used.”
Sergio Pérez, the Mexican driver from the Red Bull team, said that braking was a challenge at his home race. “Basically, nothing works in Mexico, and on the track the brakes are really hot,” he said. “Everything is on the edge.”
At the Mexico City Grand Prix in 2023, the driver Kevin Magnussen of Haas crashed after his brakes caught fire, and his rear suspension was damaged.
“It’s an odd race,” he said this month. “And physically you feel it too — you’re breathing more with the thin air. But for a driver it’s not really a big challenge. More for the cars.”
“Cooling the brakes and the engine and gearbox is very tricky there,” he said. “So it’s a pretty inefficient race aerodynamically for the car. And things are harder to control. As a consequence, I had that rear suspension failure because of hot rear brakes last year.”
One thing the drivers can do is deploy the “lift-and-coast” technique. They ease off the gas pedal a few hundred feet before a corner and glide toward it (like a suburban driver does on very wet roads). The brakes then don’t have to work as hard to slow the car.
“We didn’t employ that much in my days,” said Wright, who was part of the McLaren team that won the Mexico City race in 1988 and 1989. “But lifting and coasting would be of big benefit these days because then you’re not relying on the brakes so heavily.”
With all the additional considerations because of the altitude, the race usually ranks among the lowest on the schedule for overtaking, which reduces some of the excitement for fans.
“Our track and location certainly pose different challenges for teams and drivers, and how that affects performance,” said Federico González, the general director of the event. “So, strategy plays a big part.”
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