Even though General Motors sub-brand Cadillac will hit the Formula 1 grid in 2026, its in-house power units won’t appear until 2029.

But according to GM president Mark Reuss, the team’s PU division has already ticked off another major milestone: Its first prototype has already come to life.

Cadillac F1 power unit roars to life

When the FIA opened up expressions of interest from prospective Formula 1 teams back in 2023, one entry really stood out: That of Andretti Global, which would be arriving at the top level of international open-wheel racing with a General Motors partnership.

It took some internal reorganization before the outfit received approval from Formula One Management — which made it clear that while it wasn’t particularly keen on a Michael Andretti-run team, it would love to bring in GM as a power unit supplier.

FOM approval came when Andretti stepped back, allowing Cadillac to assume a front-and-center role as team owners.

Now, the team will be making its debut in Formula 1 in 2026. This initial entry is effectively the first phase of a two-part process — the first getting a team on the grid, and the second introducing the team’s power unit.

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Though that PU won’t arrive in full force until 2029, GM president Mark Reuss has big news: A functional prototype has already roared to life.

“With regard to the power unit, development is already well underway,” Reuss revealed during a press conference held in the build-up to the Miami Grand Prix and reported in Motorsport.com.

“In fact, we fired up our first engine last week.”

GM then shared images of the PU on a test bench.

Of course, this is still a prototype, which means it’s far from being the final version of the PU that will make it into the Cadillac chassis — but the fact that development is already so advanced is a great sign, particularly because the official PU facility in North Carolina won’t be complete until 2027.

Examples of the chassis, too, have entered production.

“We are working on the cars. We have been in the wind tunnel for a long time. The chassis has arrived, we continue to add people to the team. There are so many work streams that are all happening at the same time,” Cadillac representatives said in Miami.

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