Williams publishes FW48 car weight as rumoured F1 2026 fears eased

Williams has confirmed that the new FW48 has weighed in at 772.4 kilograms following the launch of its F1 2026 car on Tuesday.

It comes after James Vowles, the Williams team principal, moved to ease concerns that the car is significantly overweight.

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Williams was the only team to miss the five-day shakedown in Spain last week due to what the team described as “delays in the FW48 programme.”

The team’s absence led to speculation that the car is significantly over the minimum weight limit of 768kg for the F1 2026 season.

The Grove-based outfit held a season-launch event on Tuesday, revealing its revised livery for the new campaign.

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Williams also put to bed claims that the FW48 is hugely overweight by publishing the its technical specification, with the 2026 machine coming in at 772.4kg – 4.4kg over the minimum limit set by the regulations.

For context, Williams engine supplier Mercedes confirmed earlier this week that the factory team’s 2026 car, the W17, weighs 772kg – just 0.4kg lighter than the FW48.

Speaking to PlanetF1.com and other media outlets on Tuesday, Vowles said of concerns over the car’s weight: “In terms of weight, until there’s two race cars built in the correct specification going forward, it’s hard to comment on that one.

“But even so, in that regard, your question was: does that stop you being competitive right now?

“No one knows – and I really do mean no one – what the pecking order is, especially ourselves as we haven’t been on track, so it’s hard for me to answer that question.”

Vowles’ latest comments come after the Williams boss last week vowed to activate an “aggressive programme” to drop the car’s weight if it proves an issue in next week’s second pre-season test in Bahrain.

“There’s no knowledge of the weight until we get to Bahrain in terms of understanding where it is,” he added.

“There’s not a single person who will truly know it.

“It’s impossible to know it, because you need the car together with sensors in the right form and that doesn’t exist today.

“If we end up being over the weight target, then from that point on it’ll be an aggressive programme to get it off.

“But I think right now, anything that you’re seeing as murmurings in the media is murmurings.

“I’ll come out and explain to everyone at the point where we know that.

“That isn’t today.”

Excess weight has regularly been an issue for teams at the start of a new rules cycle.

Red Bull famously began F1’s ground-effect era with an overweight car in 2022, with then-team principal Christian Horner revealing in 2023 that the team “managed to get 20 kilos out of the car” from one season to the next.

An overweight car did not stop Red Bull easing to the drivers’ and constructors’ world championships in 2022 with Max Verstappen winning the title with a then-record 15 race victories.

Additional reporting by Thomas Maher

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