2026 Drama: Alleged engine loophole

[PlatinumZealot]

As hollus mentioned, that's right for the coolant. Rod beam temperatures are likely more towards 200 than 130.

I'm sorry but he should be corrected.
There is F1 telemetry screens showing F1 coolant temperatures and oil temperatures.

The bulk temperature of the block is not to be confused with it's surface temperature.

Be that as it may, can we agree that what is cooled should be hotter than what is cooling by very simple thermodynamical principles?

You basically didn't read my comment. Hehe.

[vorticism]

The fact that these questions did not arise in 2025 and prior when the limit was 18:1 may suggest that there's nothing to the rumors nor the FIA directives/rule changes. Was it not advantageous to exceed 18:1 in 2025? What did the test entail last year? Was it not tested?

law of diminishing returns :
how much more can be increased beyond 18:1 until knocking starts to happen ? 19 ? I don't think so. Probably some 18.5 (max). That's nothing like going from 16 to 18, which can be easily accommodated knock-free, since they have already done 18 previously.

That may be, although CR shouldn't be evaluated in isolation. For 2026, there is ~30% less fuel in the cylinder per cycle, and the engine has the same displacement (swept volume per FIA), which implies less fuel per CC volume although the boost pressure is now limited as well (4.8bar iirc). The leanness of the a:f ratio may or may not be reduced depending on what that figure is. If it's leaner then exceeding 16 may not be as easy as you think, hence that regulation--i.e. the charges are in fact leaner and it is too R&D intensive to exceed 16.

Sidenote: that the displacement is the same but the GCR is reduced means that the TDC CC volume is larger than last year.

The fact that these questions did not arise in 2025 and prior when the limit was 18:1 may suggest that there's nothing to the rumors nor the FIA directives/rule changes. Was it not advantageous to exceed 18:1 in 2025? What did the test entail last year? Was it not tested?

“5.4.6 No cylinder of the engine may have a geometric compression ratio higher than 18.0.”

Source: https://www.fia.com/sites/default/files ... -04-07.pdf

That's all it states in last year's regulations. That the FIA modified it in October for 2026 is very funny.

For 2026 (the 2023 and 2024 editions state)

No cylinder of the engine may have a geometric compression ratio higher than 16.0. The
procedure which will be used to determine this value may be found in the Appendix to the
Technical and Sporting Regulations.

Source: https://www.fia.com/sites/default/files ... -06-20.pdf (June 2023)

It's interesting that they added an extra line compared to the previous regulations. Almost like they wanted someone to exploit the loophole?

I'm not sure why they added that line, but its absence didn't necessarily imply that it wasn't inspected. The regs are full of limits and dimensions alone, whether they are commonly inspected or not, whether they have a dedicated procedural document or not. It could just be a clarification--these regs are more wordy and attempt to leave less doubt.

Why add that spec (in 2022 or whenever it was) and then never test for it?

[autodoctor911]

How does this chamber with a small hole work? People say that when heated the small hole closes, but shouldn't the small hole become a bigger hole when heated?

Maybe the chamber gets filled with fuel or something else when operational.

My thought is that within the chamber there is something in close proximity to the opening which with expansion closes the gap to the hole. Yes a hole in a surface will grow with heat in most cases

[FittingMechanics]

If we assume the engine does not pass the hot tenperature test at this moment, how can Mercedes pass the test in August? I thought engines are homologated and only slow engines get development time?

[WardenOfTheNorth]

If we assume the engine does not pass the hot tenperature test at this moment, how can Mercedes pass the test in August? I thought engines are homologated and only slow engines get development time?

Why would we assume that? I think most people have accepted that the new test temperature is way lower than the temperature that the combustion chamber actually reaches.

[WardenOfTheNorth]

What is an "e-vote" and why is the FIA making a spectacle out of this?

Electronic vote - probably via email. And to try and shut down all the speculation.

[FittingMechanics]

If we assume the engine does not pass the hot tenperature test at this moment, how can Mercedes pass the test in August? I thought engines are homologated and only slow engines get development time?

Why would we assume that? I think most people have accepted that the new test temperature is way lower than the temperature that the combustion chamber actually reaches.

I agree but I see many complaining about half a season with illegal engine. Do they expect the engine to fail in August or will Mercedes (and others) get a free upgrade.

[autodoctor911]

I'm pretty sure the August timeline is to get a more fair test procedure implemented with equipment not yet available. All to do a test that still can't catch what they want to try and catch. Need to just eliminate the loophole by rewriting the rule for next year

They will have to specifically prohibit any device that can change the volume of the combustion chambers by an opening that may close off during operation or whatever the best legal technical way of doing it is. No physical procedure will cure this and can't change the rule now for this year

[autodoctor911]

Plus. They still have to test and develop the procedure to make sure it doesn't fail everyone

[Badger]

Wolff on illegal fuel, compression ratio, and if he's in the Epstein files.

We were told compression ratio is something where we were illegal, which is total bullshit, utter bullshit,"

"Now the next story comes up that our fuel is illegal. I don't know where that comes from, and it starts spinning again.

"Maybe tomorrow, we're inventing something else that I don't know - I've been on the Epstein files. God knows what?

"So another nonsense. You know, this is a complicated topic with the process and all of this, but I can't even comment."

We said it all along that this looks like a storm in a teacup, the whole thing, and the numbers that were coming up, if these numbers would have been true I absolutely understand why somebody would fight it," he said.

"But eventually it's not worth the fight. It doesn't change anything for us, whether we stay like this or whether we change the new regulations."

"I think the way it's been done now, that it needs to be compliant to the regulations when it's cold and when it's hot, doesn't give anybody an advantage,"

"I think the attempt was from the other guys to have it only measured hot so they could actually have it cold outside of the regulation. So now it's a fair game for everyone."

https://www.the-race.com/formula-1/merc ... y-rumours/

Certainly not the calmest figure in the paddock today, seems quite irked. What he says at the end is interesting, because it suggests some cars may actually be running lower compression at operating temperature than ambient. This was something Mark Hughes said in a podcast recently too, that cars were actually reducing their CR slightly at temperature. (due to expansion of the cylinder exceeding expansion in the rods and piston).

[FittingMechanics]

Toto spin machine.

Others wanted to exceed 16:1 when cold , his theory implies others have illegal engines at the moment. Spin spin spin.

[Real PJ's Beard]

I think the biggest clarification that's needed is around the 130C temperature. What is it that's going to be 130C? Block? Coolant? Oil? Different answers there affect the outcomes they'll get and they could genuinely get caught out on an interpretation (how ironic)

[autodoctor911]

I think the current solution is the only one possible. It should have to comply at all times, yes. But the only way you can measure it is to physically measure it somehow then calculate it. Unless you have xray measuring tools and can do that on a chassis dyno all you can do is fill it with something while it is hot

[autodoctor911]

If you make the chamber opening not only temperature dependant but also dependent on a pressure diffential in a particular direction once closed up thermally. Like a check valve

[dialtone]

I think the current solution is the only one possible. It should have to comply at all times, yes. But the only way you can measure it is to physically measure it somehow then calculate it. Unless you have xray measuring tools and can do that on a chassis dyno all you can do is fill it with something while it is hot

Technically the FIA could threaten Mercedes to sue them, or seize the engine to check exactly what is happening, or add specific sensors just to Mercedes without changing any rule or going through the PUAC, you know... like they did with Ferrari in 2019.