Mercedes’ rivals can point to the 2026 rules reset and insist the playing field has been levelled by tighter power unit policing. On paper, that’s broadly true: the regulations are explicit that a manufacturer must homologate one specification for everyone it supplies, with only fuel, oil and wiring allowed to vary. Same hardware, same control software, same operational capability — end of discussion.
Except it isn’t, not really. Because the real fight under a new formula isn’t only about what’s inside the engine; it’s about how quickly you can shape the entire car around it, and how many real-world laps you can use to iron out the messy details that never show up in a homologation dossier.
Bernie Collins has been outlining why Mercedes will start 2026 with two subtle, but potentially decisive, edges over its own customer teams — and, by extension, over manufacturers with fewer cars gathering data. The first is the one anyone who’s lived through an engine change recognises immediately: integration.
Mercedes, as a works team, doesn’t “receive” a power unit package in the same way McLaren, Alpine and Williams do. Brackley and Brixworth can iterate together from day one, deciding not just the headline dimensions but the awkward bits — the routing of pipes around the engine, the placement of ancillaries, where the oil pickup sits, how tightly everything can be packaged without turning routine maintenance into a nightmare. Those decisions are where weight comes off, where bodywork gets slimmer, and where cooling becomes a design choice rather than an emergency.
For customers, even in a modern era of sophisticated data sharing, there’s a natural lag. Collins, speaking to Sky F1, described it through the lens of her time in a Mercedes-customer environment: you’re building your car around a CAD model that updates periodically, while the works outfit is effectively working on the live version. That difference sounds administrative until you’ve been burned by it — you commit to a layout, the engine model changes, and suddenly a part that cleared yesterday doesn’t clear today. The result is rarely one catastrophic failure; it’s death by a thousand delays, and the calendar is ruthless when you’re trying to launch a new-generation car.
That’s a particularly sharp point in 2026 because the power unit architecture itself has shifted. The MGU-K has been dropped and the balance between electrical energy and the combustion side is now a straight 50:50 split, with fully sustainable fuel in the mix. Even for teams that have lived comfortably in the hybrid era, this is a major repackaging problem. Energy systems, cooling requirements and the way teams chase efficiency are all being re-optimised at once — and that makes the “we can integrate from the start” advantage feel less like a nice-to-have and more like a head start.
The second edge Collins highlighted is less visible to fans, but engineers talk about it constantly in the paddock: mileage equals knowledge, and knowledge arrives faster when you’ve got more cars on track.
Mercedes has four teams’ worth of running feeding back into the same power unit programme — its own works entry plus McLaren, Alpine and Williams. That doesn’t mean Mercedes can magically develop four different engines; the rules are clear on supply parity. But it does mean the manufacturer has far more opportunity to spot trends, identify weaknesses and understand how the unit behaves across different chassis philosophies, different cooling concepts and different operational styles.
If one customer runs aggressively with tight bodywork and another chooses a more conservative cooling approach, you end up with a broader map of what the power unit tolerates, where it drifts, and what needs attention. It’s not hard to see why a manufacturer with a single team — Audi, or Honda supplying Aston Martin — might feel they’re fighting with one hand tied behind their back in the early races, when every weekend is effectively a live test session.
There’s also an important psychological component here. Customer teams will naturally focus on their own performance problems first: balance, tyres, aero correlation. They can flag power unit issues, of course, but they don’t have the same incentive to run experimental configurations or chase edge-case diagnostics unless it’s directly in their interest. A works team can decide that sacrificing a slice of Friday is worth it if it helps the bigger programme.
All of this sits under the broader reality of 2026: even before the first proper competitive laps, the power units are already drawing scrutiny. Mercedes and Red Bull have reportedly found themselves at the centre of early-season noise around a potential loophole related to compression ratios — specifically the allegation that an engine designed to meet the 16:1 limit when measured at ambient temperature could effectively see that ratio rise at normal operating temperatures. The performance implications being whispered about are exactly the kind that cause paddock paranoia: more power, better fuel efficiency, and enough lap time to turn a close midfield into a clean break.
None of this is proof of wrongdoing — and in a regulation reset year, “loophole” is often shorthand for “someone read the wording better than we did”. But it does underline why integration and data volume matter so much. If your package is already tight, your cooling is already under control, and you’ve got four teams feeding you real-world information every week, you’re far better placed to either exploit the grey areas or defend yourself when rivals come hunting for them.
The irony is that the 2026 rules are trying hard to make customer parity real. The homologation language is explicit, bordering on paranoid. Yet the sport has never been only about identical parts; it’s about timing, iteration and the speed with which you turn information into performance.
Mercedes’ customers may receive the same power unit as the W17, but they won’t receive the same development rhythm — and in a year when everyone is relearning what “fast” looks like, that rhythm could be worth more than any headline number on a dyno sheet.
