Honda’s RA626H has only just been wheeled into the spotlight, but the subtext at its Tokyo launch was less about shiny casings and photo ops, and more about the oldest game in Formula 1: how hard you can lean on a rule before someone decides you’ve gone too far.
Aston Martin chief strategy officer Andy Cowell and Honda Racing Corporation president Koji Watanabe both found themselves fielding questions about the growing paddock chatter around cylinder compression ratios in the 2026 power unit regulations. The allegation doing the rounds is that two manufacturers have found a way to turn a tightly defined limit into something a little more… elastic, by exploiting how the ratio is assessed at ambient temperature rather than in the far more hostile reality of a fully heat-soaked engine on track.
If that sounds like the sort of technical fine print that only matters to engineers, it’s worth remembering what’s at stake. At the start of a new regulation cycle, a “small” interpretation can be the difference between being a benchmark and spending two seasons digging out of a hole. Compression ratio sits right at the heart of thermal efficiency. Nudge it in your favour and you’re not talking about a vanity gain; you’re potentially shifting the balance of power and fuel consumption in a formula where everyone is hunting marginal advantages.
Watanabe didn’t try to shut the topic down so much as widen the frame. His message, delivered through a translator, was that compression ratio is merely one of several areas that, in Honda’s view, still needs discussion with the FIA as the sport closes in on the new era.
“This year, as far as the new regulations, the interpretation of the regulation and the operations for it… there are a lot of factors that need to come in discussion,” Watanabe said. He pointed to what every manufacturer privately acknowledges when the rulebook lands: not everything is “listed very clearly”, and where there’s space, there’s incentive.
“There is a lot of room for interpretation as well, and this is also part of the race,” he added, striking a tone that will sound familiar to anyone who’s watched F1’s regulatory push-and-pull over the years. The key line, though, was the one that underlines where Honda is positioning itself: it wants clarity, and it wants it through consultation rather than confrontation.
“For Honda, we have a lot of different ideas and we would like to discuss with the FIA to understand if our ideas are accepted or if it’s not okay,” Watanabe said. “We would always look to the FIA, to consult with them, on regulation related matters.”
That’s a diplomatic way of saying Honda is going to play the game, but it doesn’t want to be the manufacturer left discovering, too late, that the goalposts have been moved by someone else’s clever reading.
Cowell, for his part, sounded like a man who has lived through this movie before — because he has. He was central to the Mercedes power unit project that arrived in 2014 with such a step change that rivals spent years trying to understand where the time had gone. If anyone in the Aston Martin-Honda orbit knows how early-regulation advantage is built, it’s Cowell.
“There’s always a topic that bubbles up when new regulations come into place,” he said. “Every competitor reads the regulations and pushes performance to the limit.”
He didn’t pretend compression ratio was a minor detail. Quite the opposite. “Compression ratio is clearly a key thermal efficiency enabling aspect of an internal combustion engine, so you always push it to the limit. I’m sure every single power unit manufacturer is doing that.”
That last sentence matters. Cowell isn’t singling out villains here; he’s normalising the behaviour. In other words: if you’re surprised teams are exploring the edge of a measurement defined at ambient temperature, you haven’t been paying attention to how F1 operates when the rulebook refreshes.
Still, neither Cowell nor Watanabe attempted to adjudicate the merit of the alleged loophole in public. They pushed the responsibility back to where it inevitably lands.
“The FIA have the job to make sure that everybody interprets the regulations in a fair and equal way, which is what’s ongoing at the moment,” Cowell said.
The timing is interesting. Honda’s launch wasn’t just a technical unveiling; it was also a statement of intent as it switches its factory support to Aston Martin. Lawrence Stroll was on stage alongside Cowell, Watanabe and Honda CEO Toshihiro Mibe, underscoring how seriously both sides are selling this as a full-blooded works-style relationship rather than a loose supply arrangement.
There was also an unmistakable sense of Honda wanting to draw a line under the slightly ambiguous optics of its final Red Bull years — officially “at arm’s length”, in practice still deeply involved. Now, with Aston Martin, the branding and the accountability are much more direct. If the new era begins with regulatory grey areas, Honda will want to be seen as both competitive and correct — and those two aims don’t always sit comfortably together in this sport.
What happens next sits with the FIA’s appetite for early intervention. Clamp down too hard and you risk writing away legitimate innovation. Leave things too open and you can end up with a regulation set that effectively rewards whoever was boldest in the gaps.
Either way, Honda’s first big 2026 moment has landed with an extra layer: the RA626H isn’t just being built to the new rules, it’s being built around the question of what the new rules really mean once the engines fire up in anger.
