Audi has joined calls for the FIA to investigate potential loopholes in the 2026 Formula 1 engine regulations concerning compression ratios. Manufacturers like Mercedes and Red Bull are accused of using materials that allow higher ratios at operating temperatures, potentially gaining up to 15bhp. A key meeting is set for January 22 to discuss dynamic measurement methods.
The controversy over compression ratios in Formula 1's 2026 power units echoes past technical disputes, such as the 2009 double diffuser row and 1980s ground-effect loopholes. Under the new regulations, the compression ratio is capped at 16:1, down from 18:1, but measurements are taken only in ambient conditions, not during operation. This has led to claims that Mercedes and Red Bull employ connecting rod materials with thermal expansion properties that increase the ratio when hot, bypassing the intent of the rules.
Audi technical director James Key, speaking at the team's 2026 car launch in Berlin, emphasized the need for a level playing field. "We have to, as we do, trust the FIA with making the right decisions here," Key said. He drew parallels to the 2009 diffuser controversy, where teams like Brawn benefited from a loophole others couldn't exploit due to prior design choices. "If someone came up with a clever diffuser and you said it's not the right thing to do, no one else can have it, but you can have it for the rest of the year. It doesn't make sense. We'd never accept that."
Audi chief operating officer Mattia Binotto warned of a "significant gap" in performance, estimating gains of 10-15bhp, equivalent to 0.3-0.4 seconds per lap. "If it's real, it is certainly a significant gap in terms of performance and lap time," Binotto stated. Audi, alongside Ferrari and Honda, has written to the FIA demanding clarity, with a meeting scheduled for January 22 to explore real-time measurement techniques.
Red Bull Powertrains director Ben Hodgkinson dismissed the uproar as "a lot of noise about nothing," insisting, "I’m confident that what we’re doing is legal." The FIA maintains there is no evidence of rule-breaking but has a performance-balancing mechanism called ADUO for upgrades. Cadillac F1 chief Graeme Lowdon expressed confidence in their Ferrari-supplied engine, saying, "We have a fully legal engine," and noted the regulations are clear in black and white.
No immediate rule changes are expected, as discussions focus on long-term solutions to ensure fair competition under homologated power units.