The FIA has announced that its ADUO regulations, aimed at lagging power unit manufacturers, will commence after the Formula 1 Canadian Grand Prix weekend.

The 2026 season has ushered in F1’s latest era, with a truly hybrid 50-50 power unit propelling the cars for the very first time in the sport’s history.

That said, this massive technical regulatory overhaul has also induced a substantial gap between engine manufacturers with some getting it right and some disastrously lagging behind.

The governing body of the sport, the FIA, has taken cognisance of this and initiated its Additional Development and Upgrade Opportunities (ADUO) scheme.

Initially scheduled to come into effect from the Miami GP onwards (the sixth round of the season), the cancellation of the Saudi Arabian and Bahrain races pushed this back.

Now, the FIA has revealed that the scheme will activate upon the conclusion of the race weekend at the Circuit Gilles Villeneuve – the sixth race of the adjusted F1 calendar.

“Article 4.2 of Appendix C5 of the 2026 F1 Technical Regulations divided the 2026 season into three periods during which ICE performance will be analysed in order to determine whether a manufacturer might qualify for ADUO,” read an FIA statement.

“These 3 periods cover, respectively, races 1-6, 7-12, and 13-18. However, the first period, encompassing the Australian, Chinese, Japanese, Bahrain, Saudi Arabian and Miami grands prix was disrupted by the ongoing events in the Middle East.

“The first period has therefore been adjusted and is now formed of the season’s first five races (Australia, China, Japan, Miami and Canada). The results will be communicated no later than two weeks after the Canadian Grand Prix.”

Which F1 engine manufacturers are eligible for ADUO?

Currently, five engine manufacturers have entered their power units on the grid.

Some of them have done exceptionally well, both, in terms of performance and reliability such as Mercedes. However, PU manufacturers like Honda have had a troubled start to the 2026 campaign.

Naturally, the Japanese Automobile giants are slated to receive ADUO – which has been reserved for manufacturers whose performance index is at least two per cent but less than four per cent below the best-performing engine.

Qualifying for ADUO will mean a chance to develop its engine – beyond the cost-cap and testing restrictions in place – and the list will be revised on two more occasions this season.

“The 2nd period will cover races 6-11 (Monaco to Hungary) and the 3rd period from race 12 (Netherlands) to race 18 (Mexico City),” the statement continued.

“Once the results have been communicated, ADUO eligible PU manufacturers will receive a separate notification detailing their allowance.

“They will be able to implement upgrades as early as the following race.”

As things stand, the likes of Ferrari and newcomers Audi might also be included in the first ADUO list.

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