Cadillac F1, Front Brakes and the Sepang Test: When Bottas Regained the Right to Brake Late

Inside the Cadillac garage in Baku, there was one detail I noted in my notebook before the race began: the inlet and exit profiles of the MAC-26's front brake cooling had changed completely from the version I photographed at the Hungaroring early in the season. No press release mentioned it. No render was published. There was only a re-angled duct, an exit vent extended by a few millimetres, and a mechanic crouching to check clearance with a feeler gauge. Details like that never reach a team's website, yet they are often where a season's real story begins.

Weeks later, Valtteri Bottas told me that upgrade had lowered front brake temperature by roughly 100°C. He said it as calmly as if reading the water temperature in a room. For a new team that had just lost at least four race results to brake overheating, a 100°C difference is the gap between finishing and sitting in the garage watching telemetry screens.

I start from junior-series data; every figure is a drumbeat before kickoff. Here too: before trusting any praise, I go looking for the chain of events that produced the result.

Context: a new team and the price of heat

Cadillac entered the 2026 season as one of the paddock's newest names, carrying Ferrari power units and a technical structure built from scratch. In the garage, the senior faces were all people who had passed through big teams: Craig Skinner from Red Bull, Eric Blandin from Aston Martin, Tim Lean in charge of operations. A young team stitching scattered pieces of experience together, and like every young team, it pays for lessons the established outfits learned long ago.

Cadillac's first lesson of the season was called brake heat. Front brakes absorb most of a race car's deceleration force, and once heat builds past the threshold, pads glaze, discs crack, and the electronics have to intervene to protect the system itself. When that happens at over 300 km/h, the driver is no longer racing; he is just trying to bring the car home.

The MAC-26 had a structural weakness in its front brake cooling. At the Hungaroring, Bottas retired. In Monaco, he retired again. In Austria, at the Red Bull Ring, he retired once more. Sergio Perez stopped at the Red Bull Ring too. Combined, the new team lost at least four race results to a technical detail that should have been resolved in pre-season testing. In a season where every point matters for a new entrant, four retirements are a loss no development promise can offset.

By the Spanish Grand Prix, the problem remained unresolved. Both drivers had to actively manage brake temperature throughout the race: braking earlier, lifting earlier, keeping distance from the car ahead to avoid hot air. That is how a team races when it is surviving, not when it is attacking. When a driver must think about the car more than about the rival ahead, that team has already lost part of its advantage before the lights go out.

Every contract is a reel shot from when the player was still training on a dust pitch. For Cadillac, those technical contracts only count once the car can run a full race distance.

Core analysis: the path of a fix

What I want readers to grasp is the development path, not the final result, because the path reveals whether a team has a process or merely one lucky break.

The chain ran like this. Early in the season, Cadillac ran the original brake cooling spec and quickly found the thermal margin too narrow. At the Hungaroring, the team brought a first upgrade, altering the inlet surfaces and aperture. It did not solve the problem. At the Azerbaijan round in Baku, the team switched to redesigned inlet and exit duct profiles, and this time the result was markedly better. It is a familiar development loop: form a hypothesis, test it on track, fail, re-read the data, and fix.

The credible technical step is not that the team found a miraculous solution, but that it dared to replace a failed approach with a different one. That signals a normal development process, where engineers learn from track data and adjust, rather than a one-off lucky fix. Backmarker teams often fail at exactly this point: they keep a broken approach because they fear losing test time.

Bottas says the new package cut front brake temperature by about 100°C. That is team- and driver-reported data, not independent telemetry I can verify from a third source, so I note it with a question mark beside it. A 100°C reduction tells us the thermal margin has improved, but not whether the braking system can endure an entire stint at a hot, abrasive, high-braking circuit. A few laps of cooler temperatures and 50 laps of survival are two different stories.

Alongside that, the team received a minor power-unit update from supplier Ferrari. Perez describes that step as worth only about a tenth and a half per lap. For a team at the back, that is not enough to change its competitive tier; it is only enough for the car to be less exposed on the straights.

From my experience following races, I always separate two kinds of updates: those that improve qualifying pace and those that improve the ability to finish. The brake fix belongs to the second. It does not make the MAC-26 noticeably faster, but it can return points that were previously lost to retirements. On the results sheet, a slow car that finishes still beats a fast car sitting in the garage.

Contrarian angle: the trap of optimism

Once the team confirmed the temperature drop, the story is easily told as Cadillac having solved its brake problem. I do not read it that way, and here is why.

First, the 100°C figure is team-reported. There is no independent on-track data, no pit-stop numbers, no public telemetry to cross-check. When an indicator comes from only one side, it is a signal, not yet proof. I keep my rule of cross-checking multiple sources before turning a number into a conclusion.

Second, enlarging or redesigning cooling inlets and exit ducts usually carries an aerodynamic drag cost. A bigger inlet can take away some straight-line advantage. At a power-sensitive circuit like Sepang, that trade-off could erode the very gain the fix delivers. The team has published no drag figure, so I leave that possibility open rather than dismissing it.

Third, the power-unit update is worth only about a tenth and a half per lap. Readers expecting a leap from it will be disappointed. The engine does not change Cadillac's position in the standings; the brakes are what decide whether the team finishes at all.

Finally, Perez himself says Cadillac will still struggle at Sepang. A driver who knows his car well usually judges it better than any outside praise. When an insider is cautious, I tend to trust that caution over optimistic headlines.

What can be inferred but the team has not said

Two points strike me as reasonable but unconfirmed. One is that cooler front brakes may reduce pad and disc wear, letting drivers brake later and harder in heavy braking zones and indirectly improving lap time. The reasoning is sound but confidence is only medium, since the lap-time effect also depends on how the driver uses the new margin. The other is that better thermal margin may let the team run more aggressive brake-balance maps across a stint, indirectly affecting tyre temperatures and degradation. Both need track data to verify, and either could be disproved within a single hot race.

The Sepang test and what to watch

Sepang is the right test. A hot climate, long sweeping corners and repeated heavy braking zones will punish the braking system far more than a cool European round. If the fix is only marginal, Cadillac will have to revert to a conservative mode: safe brake maps, earlier braking, earlier lifting. If the fix genuinely solved the problem, the team can let its drivers attack in the closing laps of a long stint.

What I am waiting for is not the qualifying position, but Bottas's braking behaviour over the final ten laps. When the stadium falls silent, I learned to hear the team through every page of notes. Here too: I do not listen to the statement, but to whether the driver dares to brake late.

Conclusion

A brake fix is not a glamorous story. It produces no fastest laps, no beautiful overtakes, no catchy headlines. It simply returns to a new team the right to race normally. But for Cadillac, the right to race normally is the biggest step of the entire season.

Data does not know impatience; it waits for me to read carefully before trusting emotion. I will wait for Sepang, to see whether the 100°C reduction turns into a full race distance or merely a pretty improvement on paper. If Bottas and Perez still have to brake early in the closing laps, then the new team's brake-heat lesson is not over yet.