McLaren’s Mercedes Power Unit deficit shows F1’s new customer-team reality

Same Hardware, Different Advantage

The FIA’s Formula 1 regulations guarantee customer teams access to the same power unit specification as the manufacturer’s works outfit. Yet the emerging complexity of the 2026 systems has put a sharper emphasis on something the rulebook cannot equalise: experience in extracting performance.

Historically, works status has carried advantages, even if customer teams have still claimed championships, including McLaren in the past two years, Brawn in 2009 and Red Bull during its title-winning period with Renault. During the hybrid era, the FIA moved to ensure equal engine specification for customers, and as development matured, power units became less visible as a performance differentiator.

Energy Management Returns To The Foreground

The increased role of the MGU-K has made energy management a more decisive performance factor, with software systems now significantly more sophisticated than those used previously. Customer teams still receive direct manufacturer support in the garage, but the responsibility for optimising the power unit remains with the team itself.

A supplier can answer technical questions and provide support, but it cannot guide a customer through performance extraction in the same integrated way that occurs inside a works operation.

At Silverstone, Andrea Stella made clear that McLaren’s deficit cannot be explained only by car development. His comments also sit alongside wider concerns over McLaren’s recent performance trajectory, including the upgrade timing issues covered in our analysis of Stella’s view on McLaren’s Silverstone slump.

Stella said Silverstone placed heavy emphasis on energy usage and power unit performance. “We still seem to have a little bit of a deficit in extracting the most from the HPP power unit,” he said, adding that GPS overlays suggested McLaren was leaving performance behind.

The Limits Of Equal Supply

Attention also turned to a Mercedes qualifying feature, with George Russell and Kimi Antonelli briefly lifting before the finish line. Stella admitted the tactic surprised McLaren and said it was not something the team had discussed or was sure it could access without further elements.

McLaren is also waiting to see whether it can receive the latest Mercedes specification, although Stella described it as a reliability upgrade and stopped short of claiming it would solve the performance question.

The broader lesson is clear: equal hardware does not automatically mean equal exploitation. In modern F1, the works advantage increasingly lies in accumulated know-how — developing, calibrating and managing systems so complex that the final tenths may depend less on what is bolted into the car, and more on how well a team understands how to use it.