Mercedes' new engine upgrade plan is terrible news for Ferrari

Mercedes is working on what could be a killer blow to rival Ferrari's fading 2026 Formula 1 title chances with an ADUO-assisted engine upgrade set for introduction.

Despite it being accepted in the paddock that Mercedes has the best complete power unit package, it has earned the right to bring a development step this year under F1's catch-up mechanism known as Additional Development and Upgrade Opportunities (ADUO).

That is because the FIA's analysis of the different manufacturers has concluded that, based on the internal combustion engine element that ADUO is judged on, Red Bull is more than 2% ahead of everybody else.

It means Mercedes has the right to bring one power unit upgrade this season and one in 2027, while Ferrari, Audi and Honda can bring two this year and two next. Red Bull is not allowed any improvements yet.

Mercedes had declared earlier this season that, while it would be making use of the extra test bench hours and development spending that has been opened to it through ADUO, it did not plan to introduce any hardware changes.

However, The Race has learned that there has now been a change of plan and that efforts are ongoing at Mercedes' Brixworth engine facility to ready an ADUO step before the end of the campaign.

No date has yet been set in stone for the introduction of the upgraded specification, but it is anticipated that it will likely be at some point during the upcoming triple header that comprises Azerbaijan, Malaysia and Singapore.

The timing of this could coincide with when George Russell has to take a grid drop penalty for fresh power unit components, with him unable to get through to the end of the season on his current pool.

Clues from Antonelli's new parts

It has not been confirmed in what area the Mercedes ADUO modifications will be made, but a big clue may have come at the Italian Grand Prix through the new parts Kimi Antonelli did and did not introduce there.

The world championship leader had headed into his home race knowing that he would be starting from the back of the grid because of an engine change penalty.

However, Mercedes chose not to fit a totally new power unit and instead restricted the changes to Antonelli's internal combustion engine, battery and control electronics.

It did not fit a fresh turbo, MGU-K, exhaust and ancillaries, even though taking new versions of these would have been without consequence.

Holding fire on introducing the full suite of components suggests Mercedes plans to bring those parts later this season – with the door then open for any of these to be upgraded when they are fitted.

It is widely understood that Mercedes has little to gain through improving its ICE, and that doing so risks pulling it ahead of Red Bull and handing its rival an opportunity for ADUO.

Modifications are likely to be focused in other areas, with the turbo the most obvious area where good gains can be found.

Due to Mercedes' tactics in Italy, in terms of what it did not replace, bringing the first fresh turbo will be without penalty.

So, when any ADUO step comes then that could mean both Russell and Antonelli getting their hands on it at the same time.

Under F1's rules, if a manufacturer introduces an upgrade of specification, then this has to be made available to its customer teams.

At the first race where it comes, the works squad must make at least one version of the change available to each of its customer teams.

So, when the new part comes, Alpine, Mercedes and Williams will all enjoy any progress that has been made, even if they have to choose how best to stagger any introduction between their drivers.

This could have an impact on the fight at the front too, with McLaren's recent progress having helped it win races and any gain it has potentially giving it a further edge over Ferrari.

The arrival of the Mercedes ADUO upgrade will likely come around the time of a major car upgrade that looks set to arrive at the Bahrain Grand Prix in Malaysia at the start of next month.

With the team having been conservative with its development spending this year, it has elected to space out its introduction of major new parts.

It last introduced a major package in Montreal in late May, but is working on what could be a big overhaul for Sepang.

Hamilton says Mercedes advantage 'mind blowing'

Mercedes' plan to bring an ADUO upgrade will be bad news for Ferrari, which introduced the second of its two allowed upgrades at the Italian Grand Prix.

It is understood that the changes it made to try to improve engine power were related to the turbo – making the design bigger with some other modification to the concept aimed at helping its potential.

Ferrari had downplayed the significance of its ADUO 2 step, which was also raced by Haas's Ollie Bearman.

However, it was clear from the relative performance of Ferrari against Mercedes on Monza's straights that there remains a big differential in play.

Ferrari team principal Fred Vasseur said that his team did not have the energy available to fight properly, as rivals battled with different deployment strategies.

"[Some] were 10km/h faster on one straight and 10km/h slower on another," he said. "The issue was that we were almost 10km/h slower everywhere.

"When we were putting a bit more energy in one corner, the gap was even bigger in the next straight line. It was quite impossible to manage."

Lewis Hamilton said he was taken aback by the differences between his own Ferrari and the Mercedes.

"We knew that they were fast on the straight, but it was really mind-blowing just how quick they were on the straight," he said. "Mercedes power, that thing just keeps pulling, pulling, pulling."

Despite Vasseur singling out the deployment deficit as a limiting factor in the race, he said there was no obvious root cause for the overall poor Ferrari performance.

"When you have a lack of pure power, then you start to play with deployment to try to compensate in one straight line," he said.

"If you deploy more somewhere, for sure you will deploy less somewhere else. And then you are going in the wrong spiral to try to play with this when you are fighting.

"Honestly, it's not about deployment. I think deployment was good. Even McLaren, they were playing a little bit Friday and Saturday morning. At the end, we are missing pure power."

Despite the Monza upgrade being the second step that Ferrari has made this season, following the revisions introduced in Austria in June, Vasseur thinks the long lead times for engine changes means getting on terms with Mercedes will be a long-term project.

"We were not expecting to recover [with] ADUO 1 or ADUO 2," he said. "We are doing small steps, but what you have to keep in mind is that…even if you make a couple of horsepower, it's a good step on the grid.

"We have a new engine next year, and ADUO 1 in 2027, and ADUO 2. The target is to catch up, to catch up as soon as possible, but I was not expecting that in two months we will recover the delta with Mercedes."