Mercedes cars parked? Zak Brown responds to worst-case Australian GP scenario
McLaren have competed with Mercedes customer engines since 2021
Zak Brown, the McLaren chief executive, says he “can’t imagine” a scenario of cars with a Mercedes engine being forced out of the opening race of the F1 2026 season in Australia.
It comes after it emerged that rival manufacturers are pushing for a change to rules ahead of the Australian Grand Prix.
Zak Brown rules out Australian GP without Mercedes-powered cars
Reports over the winter claimed that two engine manufacturers – widely named as Mercedes and Red Bull Powertrains – are exploiting a loophole in the new engine regulations related to compression ratios.
The regulations for the F1 2026 season state that compression ratios must not exceed 16.0, a drop from 18.0 under the previous rules.
With compressions ratios only measured when the engine is cold, however, it is said that Mercedes and RBPT have found a way to increase the compression ratio to 18.0 when the car is out on track.
Such a trick would almost certainly provide a significant competitive advantage, improving the performance of the engine as well as fuel efficiency.
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Reports last week claimed that Mercedes’ rivals are pushing for a change to the way compression ratios are measured in time for next month’s Australian Grand Prix, potentially through the use of sensors when the car is on track.
Another possible solution could see compression ratios measured in the garage when the engine has reached operating temperature.
McLaren has competed with customer Mercedes engines since 2021, with the Williams and Alpine teams also using Mercedes power units – in addition to the factory team – in F1 2026.
All together, these teams account for eight of the 22 cars on the grid this season.
Brown has played down fears that a change to the rules could force the Mercedes-powered teams out of the season opener in Melbourne on March 8.
He told PlanetF1.com and other media outlets: “I can’t imagine that you wouldn’t have Mercedes teams on the grid in Australia.
“We’re not privy to those conversations and so I wouldn’t even know from a power unit point of view what would be required to change the regulations.
“But we’ll have all the Mercedes teams on the grid in Australia, I’m sure.”
Various meetings have been held over recent weeks in an attempt to resolve the situation before the start of the new season.
As reported by PlanetF1.com, the FIA met with “technical experts” representing the engine manufacturers on January 22, four days before the start of the first test of 2026 in Barcelona.
A second meeting with technical experts was held last Monday before the Power Unit Advisory Committee (PUAC) met three days later.
According to the governance of the PUAC, a significant and immediate change to the engine rules requires the backing of four of the five manufacturers, along with the FIA and FOM.
The stance of Red Bull Powertrains could prove crucial amid suggestions that the manufacturer hasn’t enjoyed the same success as Mercedes with the supposed loophole.
As such, it could suit RBPT to join the opposition manufacturers in a bid to close down that avenue.
Brown insisted that any efforts for a late change to the engine rules are simply part of the political game in F1, arguing that the Mercedes engine is “totally compliant” with the regulations.
He said: “It’s typical politics of Formula 1.
“The engine has been designed and totally compliant within the rules. That’s what the sport is about.
“[This case is] no different to things like double diffusers that we’ve seen in the past, where they’re compliant within the rules.
“I don’t believe there’s a significant advantage as being represented by the competition.
“But of course their job is any perceived advantage, they’ll make some story out of it.
“But the reality is the engine is completely compliant, passed all its tests, and I think HPP [Mercedes High Performance Powertrains] has done a good job.”
Asked if McLaren is involved in talks about the engine rules, he added: “We’re aware, but it’s a Mercedes topic.
“We obviously don’t build and design the power unit, so HPP does a good job of keeping us in the loop, because obviously we’re very interested.
“But we don’t sit in the power unit working group where those conversations happen.”
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