Beyond Power Unit Disparities: Unpacking McLaren's Struggles Against Mercedes in 2026

For 2026, the power unit will comprise a 1.6 litre V6 turbocharged internal combustion engine with a significantly enhanced electrical component. The MGU-H will be removed. The electrical power output will increase substantially with a more powerful MGU-K and larger energy store.

Any PU Manufacturer intending to supply a Power Unit to an F1 Team during a Championship (year N) must: a. Declare to the FIA, before 1 August of year N-1, that they provided to their customer F1 Teams: i. An initial full external space model of the Power Unit including details and locations of all physical interfaces required by the team to install the Power Unit. ii. Preliminary estimates of important operating parameters such as heat rejection, fuel mass and density, clutch shaft stiffness and engine stiffness. b. Declare to the FIA, before 1 November of year N-1, that they provided to their customer F1 Teams: i. A final full external space model of the Power Unit including details and locations of all physical interfaces required by the team to install the Power Unit. ii. Firm predictions of important operating parameters such as heat rejection, fuel mass and density, clutch shaft stiffness and engine stiffness. iii. Initial details of any other parts, procedures, operating conditions and limits or any other information required by the team to install and operate the Power Unit as intended. After the 1 August of year N-1, any significant change compared to previous communication, must be notified to the customer F1 Teams in due time. Should a Customer Team consider that the change has an unreasonable impact on the Power Unit installation in the car, they may contact the FIA within 7 days of the notification. The FIA will then contact the relevant PU Manufacturer and its customer F1 Teams in order to conduct its investigation. If the FIA is satisfied, in its absolute discretion, that these changes are acceptable, the FIA will confirm to the PU Manufacturer and the customer F1 Teams within 14 days that they may be carried out.

At the end of each of the ADUO periods specified above, every PU Manufacturer granted ADUO may implement further upgrades to their homologated Power Unit (as described in Article 3.3 of this Appendix), extend the usage of their Power Unit Test Benches for Restricted Testing (as described in Article F5.2.7) and must make a downward adjustment for Cost Cap purposes (pursuant to Article 4.1(t) of the Power Unit Financial Regulations). a. PU Manufacturers whose ICE Performance Index is at least 2% but less than 4% below the best-performing ICE will be eligible for: i 1 additional homologation upgrade in season N ii 1 additional homologation upgrade in season N+1 b. PU Manufacturers whose ICE Performance Index is at least 4% below the best-performing ICE will be eligible for: i 2 additional homologation upgrades in season N ii 2 additional homologation upgrades in season N+1 ADUO homologation upgrades are not cumulative within a season and will only be granted following the first occasion that the PU Manufacturer is assessed by the FIA as eligible for ADUO according to the criteria in this Article. [The proposed 2% threshold and subsequent resolution of the ICE performance index will be validated or adjusted after conclusion of the ongoing activities between PU Manufacturers and F1 Teams related to the on-track ICE performance measurement]