Red Bull’s PU on ‘very limit’ of rules amid F1 engine trick 'noise'

Red Bull have no concerns they are doing anything illegal with their 2026 F1 power unit amid recent “noise” over suspected engine tricks.

Much of the build up to the new F1 season has been dominated by an early controversy before a wheel has even turned after reports some teams have found a loophole in the regulations.

Rivals suspect that Mercedes and Red Bull are exploiting thermal expansion to enable them to achieve a higher compression ratio than the permitted 16:1 when their car is running. Crucially, during the FIA’s static tests, the compression ratio is within compliance.

The trick could theoretically hand teams successfully carrying it out a potentially crucial performance advantage. 

Audi, Ferrari and Honda have already raised their concerns with F1’s governing body the FIA.

Much ado about nothing?

Red Bull have admitted to taking the design of their first in-house engine to the “very limit” of F1’s compression ratio rules, but are confident it is legal.

“I think there's some nervousness from various power unit manufacturers that there might be some clever engineering going on in some teams,” Red Bull Powertrains director Ben Hodgkinson said at the team’s season launch in Detroit.

“I'm not quite sure how much of it to listen to, to be honest. I've been doing this a very long time and it's almost just noise. You just have to play your own race really.

“I know what we're doing, and I'm confident that what we're doing is legal. Of course, we've taken it right to the very limit of what the regulations allow. I'd be surprised if everyone hasn't done that. My honest feeling is that it's a lot of noise about nothing. I expect everyone's going to be sitting at 16, that's what I really expect.”

Hodgkinson feels the allowed compression ratio limit, which was originally set at 18:1 before being reduced for 2026, is too low.

“From a purely technical point of view the compression ratio limit is too low,” he said.

“We have the technology to make the combustion fast enough, so the compression ratio is way too low. We could make 18:1 work with the speed of combustion that we've managed to get, which means there's performance in every tenth of a ratio that you can get.

“Every manufacturer should really be aiming at 15.999 as far as they dare when it's measured.”

Red Bull’s RB22, which was not revealed at the launch, will be driven by Max Verstappen and Isack Hadjar for the first time during a private shakedown in Barcelona between 26-30 January.