2026 Drama: Alleged engine loophole

[Hoffman900]

If the engines measure at 16:1 at ambient, which I suspect all do, then none are legal at 12,000rpm in a firing engine.

We don't know that. While the rods may stretch at 12,000 RPM, if the head expands then it may compensate for the rod stretch. If one intended to remain under 16:1 at all times, that is what you would do.

We do know that. Every race engine builder under the sun knows that. Set your piston to head clearance too close at ambient and you’ll crash the piston into the head. I’ve seen it. I’ve also see the witness marks on piston and head to know it was absolutely on the limit. We literally build engines this way creeping up to this. We can run FEA and all that but we have no way of verifying / correlating it without a massive investment in instrumentation that it’s just easier to use progressively thinner head gaskets. Race engine builders have been doing it this for 50+ years.

Over the last 55 pages of this thread, it’s clear you haven’t built an engine or know engine building. I have / I do, and at a pretty competitive level. Just stop.

[AR3-GP]

If the engines measure at 16:1 at ambient, which I suspect all do, then none are legal at 12,000rpm in a firing engine.

We don't know that. While the rods may stretch at 12,000 RPM, if the head expands then it may compensate for the rod stretch. If one intended to remain under 16:1 at all times, that is what you would do.

We do know that. Every race engine builder under the sun knows that. Set your piston to head clearance too close at ambient and you’ll crash the piston into the head. I’ve seen it. I’ve also see the witness marks on piston and head to know it was absolutely on the limit. We literally build engines this way creeping up to this. We can run FEA and all that but we have no way of verifying / correlating it without a massive investment in instrumentation that it’s just easier to use progressively thinner head gaskets. Race engine builders have been doing it this for 50+ years.

Over the last 55 pages of this thread, it’s clear you haven’t built an engine or know engine building. I have / I do, and at a pretty competitive level. Just stop.

I'm not fighting you on your prodigal engine knowledge. You have said without any proof that other teams are operating above 16 CR when running. If a team has designed their engine to run at 16CR when running, then that's what it will do. Simples. You don't have any grounds to suggest otherwise. These teams are campaigning for the test, so logically you can conclude that they know they will pass it. Otherwise, everyone is illegal and it makes the entire inquiry moot.

[WardenOfTheNorth]

Mercedes would have an engine spec from September that complied with the regulations before the October amendment. So they can just use that right?

Have they?? Built, tested, with mapping and fuel etc all ready and available??

[WardenOfTheNorth]

Isn't this just another case of spirit of the rules?

No. You're either pregnant or you're not.

And the PU will either pass the ambient test or it won't.

[SB15]

Mercedes would have an engine spec from September that complied with the regulations before the October amendment. So they can just use that right?

Have they?? Built, tested, with mapping and fuel etc all ready and available??

Well why wouldn't they? The regulations didn't change until October so why would Mercedes have constructed an engine outside the limit before then?

of course you must think people here are very stupid. Everyone knows that Mercedes didn't develop a brand new engine with higher compression ratio in 3 months time. They've been working this angle for potentially years. Yet the FIA found it only convenient to change the regulations in October of 2025...to make the Mercedes engine legal when for years they were developing an illegal engine.

"if the engine is illegal..." We have came full circle!

This is last year all over when everyone was desperate to call the Mclaren "illegal" thanks to their tyre cooling and Flexi-wing tricks.

[dialtone]

The flexi wing is a great example here. MCL knew the testing was orthogonal weight flex, they designed their wing to torque by deliberately changing the carbon layout.

In this case Mercedes also deliberately designed the engine to go around the test. The clarification doesn’t mean much and Ferrari in 2019 asking “hey FIA, so the fuel flow sensor is the only way you measure fuel flow right?” This isn’t collaborating with FIA, this is just for show.

Design specifically to circumvent an “at all times” rule should be illegal because it was ruled illegal in the past, there’s not much to it.

Teams will accept whatever FIA chooses, but not so sure the fans will, but everything will get along.

[Watto]

I have mixed feelings on this one.


It annoying me when cleaver engineers find their way around rules finding loopholes only for the FIA to shut them down cause.....reasons.

The hesitation I perhaps have in this case is the late tocahge to ambient temperature seemed a little....off - though I have no issue with teams asking the FIA for clarification on what they can and can't do within the rules to find an edge.

[venkyhere]

The most farcical thing about this whole saga, is :
FIA ASKING THE TEAMS TO SUBMIT A METHOD TO MEASURE COMPRESSION RATIO.
why ? the people who 'frame a formula' don't have the know-how to define a way to test/measure the compression ratio of an engine ? that too, geometric compression ratio ?
I don't know whether this is FIA being lazy ? facetious ? stupid ? corrupt ? or all together ?
The more I read this thread, the more disillusioned I become.

[Bence]

If the intent is showing up to sneakily circumvent a R-U-L-E, well, that's not clever engineering, but blatant, disgusting cheating, fraud, scam. And from the point it brings imbalance to a structure, it must be eliminated. Period.

[AR3-GP]

The hesitation I perhaps have in this case is the late tocahge to ambient temperature seemed a little....off - though I have no issue with teams asking the FIA for clarification on what they can and can't do within the rules to find an edge.

That regs clarification should have come years ago. Then fair game, but it didn't.It only leaves 2 scenarios

(1) Mercedes and the FIA have known about this for years and made a late regulations amendment at Merc's request because Mercedes didn't want to tip anyone off.

(2) Mercedes never had clarification. They designed an engine that was never legal according to the existing regs, thought "oh ****", and then went to the FIA to make a deal to amend the regulations.

Either way, Mercedes 100% colluded with the FIA to amend the regulations in October and that's not right. It's corruption. That's why Mercedes will not challenge it if it goes against them. They know the email chains and messages would come to light showing how they influenced the late regulations change and it wouldn't look good for anyone involved. That's my take.

[peewon]

That regs clarification should have come years ago. Then fair game, but it didn't.It only leaves 2 scenarios

(1) Mercedes and the FIA have known about this for years and made a late regulations amendment at Merc's request because Mercedes didn't want to tip anyone off.

(2) Mercedes never had clarification. They designed an engine that was never legal according to the existing regs, thought "oh ****", and then went to the FIA to make a deal to amend the regulations.

Either way, Mercedes 100% colluded with the FIA to amend the regulations in October and that's not right. It's corruption. That's why Mercedes will not challenge it if it goes against them. They know the email chains and messages would come to light showing how they influenced the late regulations change and it wouldn't look good for anyone involved. That's my take.

Yeah, the late regulation change is the smoking gun for me. For years we have seen so many regulatory decisions involving Mercedes going a certain way but they can all be individually reasoned. Although, the hypocrisy with which the FIA dealt with the Flexi wing saga last year was also damning. Under closer inspection, this late change to the regulations cannot be anything other than collusion.

[bluechris]

I have mixed feelings on this one.


It annoying me when cleaver engineers find their way around rules finding loopholes only for the FIA to shut them down cause.....reasons.

The hesitation I perhaps have in this case is the late tocahge to ambient temperature seemed a little....off - though I have no issue with teams asking the FIA for clarification on what they can and can't do within the rules to find an edge.

I am personally pretty annoyed really where only the MB stuff are "clever engineer's" or "Innovations" and all the rest are fixed immediately.

[hollus]

FIA ASKING THE TEAMS TO SUBMIT A METHOD TO MEASURE COMPRESSION RATIO.

Teams are also asked to provide an adaptor for holding the front wing planes when wing flex is measured.
This might be different… or not.
We still don’t know what is in that appendix, it might be super-restrictive in what is to tested and how, or it might be farcically loose. But we don’t know. And we don’t know what we don’t know.
Until (if) we know, going for absolutes seems a bit … opinion.

With this amount of smoke, and the sources of said smoke, it looks like there is something going on. But what? we are shooting in the dark.

[chrisc90]

When will we hear about the meeting outcome? Does anyone know what day its scheduled for?

[AR3-GP]

When will we hear about the meeting outcome? Does anyone know what day its scheduled for?

Wednesday