MPH: How FIA can intervene immediately over 'trick' Mercedes F1 engine

Part of the new regulation set for F1 for 2026 is a new performance-equalising mechanism for the engine manufacturers: it’s called ADUO (Additional Development Upgrade Opportunities). Looks like it might be needed if what we are hearing of a Mercedes advantage — apparently gained through increasing the compression ratio beyond the regulation limit of 16:1 when in operation — is true.

After every five to six races (depending upon how the calendar falls), any power unit manufacturer found to be struggling (as measured by the FIA) can be granted a combination of benefits, including additional tools and resources, increased funding beyond the PU cost cap, additional dyno hours and even the possibility of re-homologation of specifications. Furthermore, any manufacturer suffering engine failures beyond a certain threshold will be allowed to adjust their budget cap so as not to get caught in a spiral of no development budget to address the problem.

It’s an interesting development of a sport recently transformed by controlling costs simultaneously with increasing income. Not so long ago, the £4.6 billion the Mercedes team was recently valued at would have bought the entire sport twice over. In the franchise model, teams now earn enormous incomes but have their costs limited. Which is precisely why their valuations have gone crazy. The difference in income and costs has given F1 leeway to allow underachievers to attempt to spend their way back to competitiveness.

The Mercedes innovation is said to centre on increasing the length of the con-rod as it reaches operating temperature, such that the compression ratio is raised. So the piston moves further up the cylinder (reducing the volume of the combustion chamber, thereby increasing the pressures and making the mixture more explosive) and further down on the downward stroke, increasing the power stroke. There are several side benefits; the exhaust valves get more time to cool and therefore become more tolerant of bigger bangs in the combustion chamber, for example.

The engineering challenges get pretty extreme as you get up to the sort of super-high compression ratios of the previous generation of power units, whereby the maximum was set by regulation at 18:1. For the new power unit regulations, that limit was lowered to 16:1 to make it less demanding for new manufacturers. But the Mercedes PU can apparently reach the old 18:1 ratio when in operation despite being 16:1 when measured stationary and at ambient temperature. Such an increase would be worth around 10-15bhp and around 0.3sec of lap time.

The closest analogy is the flexi-wing regulations. When on track, every single car can exceed the wing flex limit demanded by the regulations. But it can only be measured when stationary and at much lower loads than seen on track. But because everyone can do it, even though the cars are all technically illegal, that impossible-to-enforce regulation will not be enforced. This is different. Because not everyone can do it. Not yet.