AUSTIN, Oct 19 — McLaren boss Zak Brown warned on Friday of "massive consequences” if champions Red Bull were found to have breached Formula One rules on adjusting car set-ups during closed ‘parc ferme’ conditions.

Red Bull have confirmed the presence of a ride-height device in their cars but said it could not be accessed once the cars were fully assembled.

The team have agreed to make changes after discussions with the governing FIA, with the device likely to have seals attached to it.

Brown said at the U.S. Grand Prix there were still questions to answer.

He said Red Bull’s statement was carefully worded, with cars not always "fully assembled” in parc ferme conditions and particularly when issues of driver comfort needed to be addressed.

"What doesn’t quite stack up is the comment that you can’t modify it,” he told Sky Sports television. "If it’s not accessible post or during parc ferme, then why put a seal on it?

"I think it needs to be a very thorough investigation because if you touch your car from a performance standpoint after parc ferme or in parc ferme, that is a black and white material, substantial breach which comes with massive consequences.”

"I think I’m not alone in our concerns for what we have seen and heard,” he added.

Red Bull boss Christian Horner said he detected "paranoia”, adding that his team were "totally comfortable” with the governing body probing the device that has become a hot talking point.

Verstappen takes pole

McLaren and Red Bull are fighting for both constructors’ championships and drivers’ titles, with Brown’s team leading the constructors’ standings by 41 points and Horner’s ahead in the drivers’, with Max Verstappen 52 points clear of Lando Norris.

Verstappen qualified on pole for Saturday’s sprint race in Austin.

There have been suggestions from some teams that such a device might allow the car’s ride height to be adjusted between qualifying and the race, which would be illegal but produce a performance advantage.

"I think there has been a bit of moaning from one of our rivals, and it is the FIA’s job to look into these things,” Horner told Sky Sports television.

"It is on a list of open-source components so it has been publicly available for the last three years. The FIA are happy with it. I think it’s just to satisfy some paranoia elsewhere in the paddock.

"If you think that there’s some kind of handbrake or lever that the drivers can activate with a low, medium or high setting, I’m really sorry to disappoint you. There isn’t.”

McLaren’s Brown accepted that drivers would physically be unable to adjust the ride height from within the cockpit.

"Our questions are a bit more around what has maybe historically happened in understanding if it’s been used in an inappropriate manner,” he said.

Red Bull have won the last two constructors’ championships, including the most dominant

season on record last year, and the last three drivers’ titles with Verstappen.

McLaren were in the spotlight at the last race in Singapore when questions were raised about their rear wing. — Reuters