Parc Ferme: Red Bull’s ADUO trap, to sandbag or not to sandbag

Back in the heady manufacture-driven days of 2022, the "ADUO" (Additional Development and Upgrade Opportunities) system must have seemed an easy band-aid to apply in the event that any one PU supplier had got a bit too clever with their design.

Implementation of the 2026 Formula 1 PU regulations was a long way off – four years, and the ramifications of racing a power-starved battery had not been investigated in any depth.

As the end of the 2025 season approached, grumbles about a Mercedes PU exploiting a regulatory loophole began to surface. By early January 2026, the details of this trick were out in the open and being circulated.

Mercedes had designed a combustion chamber that contracted at high operating temperatures but expanded at low temperatures. Since “cold’ was the condition for the ratio to be measured, Mercedes could comply but gain a power advantage when running. Clever stuff! 

Initially, Red Bull Power Trains aligned itself with Mercedes (it was rumoured they had taken a similar approach). If they had stayed on that side of the fence, the storm would have abated. However, they then changed their minds and sided with the other manufacturers in protest.

As a result, it was decided that the regulations would be changed mid-season: Compression ratios would be measured when hot (130°C) as of the 1st June 2026 – in time for the Monaco Grand Prix.

The FIA then announced the results of the ADUO benchmarking calculation at the same Grand Prix. To say that classifying Red Bull Power Trains as the benchmark PU was somewhat of a poetic farce would be an understatement. Especially as it meant that the original source of complaint – Mercedes, received a one credit upgrade.

To rub more salt into the Red Bull wound, Ferrari got two upgrade credits! The Milton Keynes outfit has, of course, launched a furious appeal on the basis that the calculation is flawed, with their evidence being that these two constructors are leading the Constructors championship. 

Any calculation can be flawed, but Red Bull Power Trains would do well to remember a couple of points. Firstly, the method of calculation was about the engine only, not who won the races or circled the track the fastest. Ferrari has done what they have done with a slower engine but a superior chassis. Parc Ferme suspects Mercedes also enjoys a good mix here but with no outright advantage.

If Red Bull’s chassis were equal to Ferrari or Mercedes, they would be the ones running away with the championship. Secondly, and more importantly, they were at the table when ADUO and the evaluation system were approved.

Is the ADUO system a good one? Maybe, maybe not, but this is irrelevant. The PU manufacturers were consulted, and they agreed on the format and testing methods. In F1, the devil is always in the details. It is incumbent on all to make the best of it if those details don’t come back to bite you. T

his weekend’s Austrian Grand Prix only increases the pressure on Red Bull. Spielberg is both their home race and a power/speed track. They will want to win here, but in doing so, they will kind of prove the ADUO system is correct.