ADUO controversy explained: are the FIA’s engine calculations missing something?. FIA says Red Bull leads, Red Bull disagrees: understanding the ADUO mystery.

The initial results from the FIA’s new ADUO engine measurement system have caught many by surprise, contradicting the paddock consensus that pointed to the Mercedes power unit as the class of the field. Unexpectedly, the official data awards the top spot to the Red Bull Powertrains-Ford partnership. However, Red Bull themselves do not agree with this assessment. This disconnect can be explained by the discrepancy between the data available to individual teams versus the governing body, though the specific formula used for these calculations may also be fundamentally unsuited to modern power units.

A matter of methodology and telemetry data

As always happens in Formula 1, every team tries to protect its own interests, but it is highly likely that the engineers at Red Bull-Ford have genuinely observed superior power figures from the Mercedes units based on straight-line performance. Estimating an opponent’s output requires precise knowledge of their aerodynamic drag levels as well as their electrical deployment strategies. This is a massive hurdle because the ADUO system isolates and measures only the internal combustion engine (ICE) power.

While teams can only make educated assumptions about their competitors’ aero maps, the FIA possesses direct measurements via torque sensors mounted on the driveshaft ahead of the gearbox. The FIA has adopted a purely statistical approach, monitoring every single car—including customer teams—across all laps while filtering out anomalies like Safety Car periods. Consequently, this ranking does not reflect pure peak horsepower, which explains why opinions on the actual competitive order differ so wildly. Instead, the final classification relies on a performance index calculated through a formula that weights engine output differently across various phases of a straightaway.

Why the 2026 power unit regulations break the formula

The underlying principle of the FIA’s current calculation is to place a higher value on the power deployed at the beginning of a straight compared to the top-end speed at the end of it. Generally speaking, having more punch out of a corner is highly rewarding, as it allows a driver to carry that initial velocity all the way down to the next braking zone. However, this may no longer be the most accurate approach for the 2026 power units, which revolve almost entirely around complex energy management. At the end of a straightaway, battery harvesting actually robs power from the internal combustion engine. At this point, the useful power pushing the car can drop below 100 hp, meaning that even a tiny discrepancy of a few horsepower becomes proportionally massive.

Defining what makes a great Formula 1 engine

There is another critical layer to consider. Any modern racing engine is a product of compromise. The sizing of the turbocharger, the packaging around the exhaust, and optimal operating temperatures are all characteristics that directly dictate ICE performance. Sometimes, engineers deliberately sacrifice raw peak power in favor of low-end corner exit torque or tighter aerodynamic packaging. A year ago, the FIA proposed incorporating these very parameters into the ADUO formula, but the teams rejected the idea. Regardless, the ongoing debate likely needs a much broader perspective.

Judging the true quality of a power unit solely by its raw thrust at the wheels risks being overly reductionist, especially since isolating an engine’s exact impact on lap time is incredibly difficult. Honda, for instance, is currently focusing heavily on combustion stability to improve drivability after their drivers reported sudden hesitations from the power unit. These anomalies do not just prevent drivers from pushing to the absolute limit; they also discourage them from using lower gears in corners to optimize battery harvesting, further complicated by the gearbox issues Aston Martin has been experiencing. Another vital factor is engine braking, which is intricately linked with both hydraulic systems and energy regeneration. This serves as ultimate proof that evaluating a power unit independently from the rest of the chassis is an uphill battle, and complicating the ADUO formula even further might not be the right way forward.

In summary, the friction surrounding the ADUO figures highlights the immense challenge the FIA faces in accurately leveling the playing field, as technical compromises between pure horsepower, drivability, and energy management continue to blur the lines of true engine performance in modern Formula 1.