Between 2014 and 2025 Formula 1 ran 252 grands prix, and Mercedes won 118 of them. The tally is not the interesting part. Most of that margin was decided before the first race of the formula, by an argument about where to put a turbocharger.
What the number actually counts
The hybrid regulations ran from 2014 to the end of 2025 — twelve seasons, 252 grands prix. Mercedes, as a constructor, won 118 of them, a shade under half (Formula 1, season-by-season records). It took the constructors' championship in each of the formula's first eight years, 2014 to 2021 (FIA); Red Bull took the next two and McLaren the two after that.
It is worth being precise about what "Mercedes won" means, because two different counts get muddled. 118 is the works team. Count every car running a Mercedes power unit — Williams, Force India, McLaren, Racing Point, Aston Martin — and the figure is 140 of the same 252 races. The engine was in the winning car more often than the team was.
The decision that made the difference
The 2014 rules replaced the 2.4-litre V8 with a 1.6-litre turbocharged V6 and five other regulated elements: the MGU-K, which harvests braking energy; the MGU-H, which harvests exhaust energy off the turbine shaft; the energy store; the control electronics; and the turbocharger itself. Every manufacturer was handed the same list of six parts. What differed was how they arranged them.
A turbocharger is normally one object — turbine and compressor bolted back to back on a short shaft, because that is the easiest way to connect them. Mercedes took it apart. The compressor went at the front of the engine, the turbine at the back, joined by a long shaft running through the vee of the block, with the MGU-H sitting on that shaft in the middle.
Three things follow, and they compound. Exhaust heat no longer soaks straight into the compressor, so the air fed to the engine starts cooler and the intercooler needed to chill it can be smaller. The compressor sits near the airbox rather than at the far end of the car, so the intake ducting is short and the engine answers the throttle faster. And the whole power unit packages tighter, which hands the aerodynamicists room they would otherwise have spent on cooling.
None of it is free. Andy Cowell, who ran the Mercedes engine division through the era, described getting the split turbo to work as "bloody hard" — a long shaft spinning at six figures wants to whip, and the bearings have to survive it (ESPN, 2016). No rival adopted the layout.
Why it stopped
The 2022 regulations moved the ground under it. Downforce came back to the floor through ground effect, and the Mercedes W13 porpoised — bouncing hard at speed as the floor stalled and re-attached, forcing the team to run the car higher than its aerodynamic map wanted. That is a chassis problem, not an engine one, which is why the engine's customers were untouched by it: McLaren, running the same power unit, took the constructors' championship in 2024 and 2025.
The end of the era is the best evidence for what caused it. When the rules changed the part Mercedes had solved, nothing happened. When they changed a part it had not, the run stopped inside one winter.
The car that started it is worth a look up close: the Mercedes W05 page pulls apart its MGU-H, and the F1 power unit anatomy lays out all six regulated elements in one diagram.
Go deeper: why the MGU-H was the hard onefor engineers
The MGU-K is a conventional problem: recover braking energy, store it, put it back. Its recovery is capped at 2 MJ per lap by the regulations, so the engineering question is efficiency inside a fixed envelope. The MGU-H had no such cap on what it could harvest from the turbine shaft, and it could run as a motor as well as a generator — spinning the compressor up before there was enough exhaust flow to do it, which is turbo lag deleted rather than reduced.
That makes it a control problem as much as a hardware one. The machine sits on a shaft whose speed is set by exhaust flow, which is set by the throttle and by how much energy the MGU-H is itself drawing off. Take too much and you choke the turbine; take too little and you waste it. Mercedes had that loop working in 2014, and mounting the machine in the middle of a long, thermally quiet shaft rather than jammed against a red-hot turbine is part of why.