Andretti Global is still ramping up preparations for a Formula 1 team despite having its General Motors-backed bid rejected earlier this year.
Andretti was given an initial greenlight by the FIA for 2025 or 2026, only to be rejected by F1's commercial rights holder (FOM) in an emphatically brutal statement that doubted whether Andretti would be a competitive proposition in F1.
The team said it "strongly disagreed" with F1's decision and dismissed two of the key rebuttals: that it was targeting a 2025 entry and that it had avoided meetings and correspondence with F1 management.
Over two months on Andretti has now formally opened a new Silverstone-based facility with an approximate Andretti Global UK workforce of 80 people.
The new 48,000-square-foot building is described as the "next stage of our preparations to enter the FIA Formula 1 World Championship" by Andretti and is an "independent property in its own name with the possibility to scale up activities as the situation evolves".
The new facility houses manufacturing and research and development facilities and will work in partnership with Andretti's Indiana site as well as the team's Formula E base in Banbury.
The F1 project is also supported by General Motors' technology centre in North Carolina.
Former Lotus and Renault Formula 1 technical director Nick Chester is spearheading the formation and development of Andretti-Cadillac's F1 project.
Last year Andretti claimed it was testing a 2023-spec in the windtunnel and has been building towards an F1 entry for some time.
"We have said that our work continues at pace – this new facility embodies that work," Andretti's statement read.
"While we are building an American works team, having a European base is a great way to attract the best in F1 talent and install state-of-the-art machinery."
Team owner Michael Andretti explained why the team's still expanding despite being rejected.
"We are still working along with FOM and we will show that we are bringing a lot to the party," Andretti told Sky Sports F1.
"General Motors is huge coming to the party. They are not just coming to be here, they are coming here to be a big part of our team, and I think it's not been understood yet how big that is.
"I think once everybody understands what we are really putting together it'll be a point where they can't say no."
FOM's indicated it might be more interested once General Motors delivers its planned 2028 engine project, but Andretti is still pushing for a 2026 entry with Renault power.
"They [General Motors] are currently building an engine. They are already registered to do it," Andretti added.
"So we will have an engine in '28, but obviously we need to build to get there. To just, all of a sudden, show up in '28 with a new engine and no team, we need two years to build there to get there that when we do get our own engine the team's ready to go and be competitive.
"So we are not naive in any way in that way.
"One thing is General Motors, it's not something that's small. General Motors has never been in Formula 1 so to have them come with us says something because they were not just going to do it just on their own, they wanted to do it with a partnership like us.
"So I think the whole way we're going about it is something that's never been done before and that's going to be huge for Formula 1, especially in the United States with having an all-American car being built in America with American owners, American engine and American driver.