Convinced that the FIA would not change anything in the way engines are measured for the 2026 regulations, and that it would allow Mercedes and Red Bull to continue with the effective increase in compression during operation (from the 16:1 specified by the regulations to around 18:1, due to heat and thermal expansion of some components), Ferrari decided to react a few weeks ago.
According to what Leo Turrini writes on his blog “Profondo Rosso”, the team led by Enrico Gualtieri is already working on a new power unit, which will not be able to be put into use before the seventh race of the season. The new “ADUO” system for reviewing engines foresees three control windows: the first opens in the sixth race and from there, teams that are at a disadvantage between 2% and 4% compared to the best engine can use an improvement. If the difference is over 4%, two improvements are allowed.
These windows will then reopen in the 13th and 17th races. However, Ferrari's project seems to be taking longer. It is known that the "trick" of Mercedes and Red Bull stems from the use of controlled expansion metallurgy, which allows the volume of some parts to increase with temperature. What is not yet clear is whether this comes from 3D-printed forged pistons, or from a channel around the spark plug that closes due to the expansion of the materials.
According to Turrini, Ferrari is experimenting with a connecting rod made of "a material with a high expansion coefficient, which allows the compression ratio to be maintained or improved when the materials expand", as the Italian journalist explains. However, he warns that "it is a solution that will take time to become functional. It is unlikely to be tested on the test bench before mid-season, so it would be a 'trick' intended for the following season, that is, for 2027".
Meanwhile, there are also doubts whether Mercedes, in a smart strategy, will immediately exploit the full potential of the new thermal engine. They can wait to see if they really need those 10 or 15 extra horsepower to win races. A slight advantage could be more useful, keeping rivals outside the 2% threshold that would give them the right to use the “ADUO” correction system. In this way, Mercedes would maintain a significant but effective lead, without allowing their opponents to immediately recover the difference.
