2026 Drama: Alleged engine loophole

[f1isgood]

I feel like the compression ratio is smoke. I think the real matter is somewhere else.

Well of course it isn't just smoke if they are scheduling meetings over it. It's real. To what extent no one knows.I agree its perhaps not the only area of interest. You don't change the engine chassis aero regs all at once and cover every loophole possible. I'm sure after Melbourne we'll here about at least 5 different loopholes being exploited.

To me its interesting because Toto went all defensive and started to attack others like him and Brown attack Horner. Thats never good imo

I think they're doing something that goes beyond regular loopholes and have a feeling that other teams know what that is and will use that.

Of course we will have theories about multiple loopholes or videos from you about something flexi soon xD

[ferkan]

One thing I am thinking…if maximum allowed compression ratio is 16:1, and people argue there is certain amount of expansion that happens to components due to high temperatures, who says you cannot run your engine at lower, at 15.6:1, 15.9:1 or whatever? Minimum is not set, only maximum.

[f1isgood]

One thing I am thinking…if maximum allowed compression ratio is 16:1, and people argue there is certain amount of expansion that happens to components due to high temperatures, who says you cannot run your engine at lower, at 15.6:1, 15.9:1 or whatever? Minimum is not set, only maximum.

Yes but why would you run lower? If i understood things correctly the larger the ratio the more horsepower.

[gearboxtrouble]

I think there are two things at play here. One is using thermal expansion to maximize the CR at operating temp. Pretty sure everyone is doing this to some extent and RBPT even said straight up they designed the engine to be at 16 when cold and higher when hot. This is normal rule optimization and seems like it would survive a challenge. Two is this recently rumored 1cc chamber that's thermally isolated from the cylinder at operating temp. This seems to have crossed the line into gaming the rules to go against what they intended and should be banned to avoid an arms race in the area. It's analogous to what Ferrari was allegedly doing to cheat the fuel flow limits in 2019. It's this recently revealed thing that the other manufacturers seem to be trying to ban and with RBPT seemingly now on board, they have the votes to force a change for this season. It's too late to change the internals at this point so Motorsport Italia is now saying that Mercedes apparently offered to race with a fuel energy flow penalty to offset the gain from the compression cheat.

[Badger]

I think there are two things at play here. One is using thermal expansion to maximize the CR at operating temp. Pretty sure everyone is doing this to some extent and RBPT even said straight up they designed the engine to be at 16 when cold and higher when hot. This is normal rule optimization and seems like it would survive a challenge. Two is this recently rumored 1cc chamber that's thermally isolated from the cylinder at operating temp. This seems to have crossed the line into gaming the rules to go against what they intended and should be banned to avoid an arms race in the area. It's analogous to what Ferrari was allegedly doing to cheat the fuel flow limits in 2019. It's this recently revealed thing that the other manufacturers seem to be trying to ban and with RBPT seemingly now on board, they have the votes to force a change for this season. It's too late to change the internals at this point so Motorsport Italia is now saying that Mercedes apparently offered to race with a fuel energy flow penalty to offset the gain from the compression cheat.

Nugnes...

This 1cc chamber thing sounds like total BS. I sincerely doubt that is the "trick".

[f1isgood]

I think there are two things at play here. One is using thermal expansion to maximize the CR at operating temp. Pretty sure everyone is doing this to some extent and RBPT even said straight up they designed the engine to be at 16 when cold and higher when hot. This is normal rule optimization and seems like it would survive a challenge. Two is this recently rumored 1cc chamber that's thermally isolated from the cylinder at operating temp. This seems to have crossed the line into gaming the rules to go against what they intended and should be banned to avoid an arms race in the area. It's analogous to what Ferrari was allegedly doing to cheat the fuel flow limits in 2019. It's this recently revealed thing that the other manufacturers seem to be trying to ban and with RBPT seemingly now on board, they have the votes to force a change for this season. It's too late to change the internals at this point so Motorsport Italia is now saying that Mercedes apparently offered to race with a fuel energy flow penalty to offset the gain from the compression cheat.

Anything Mercedes offers is useless from a performance pov. If the fia hasn't changed its compression ratio measuring methods from last regulations, no reason to change for new engine regulations either.

Imo if merc are doing something that fools the test itself which without some tricks it would fail the test then we have something a lot more serious going on

[ferkan]

One thing I am thinking…if maximum allowed compression ratio is 16:1, and people argue there is certain amount of expansion that happens to components due to high temperatures, who says you cannot run your engine at lower, at 15.6:1, 15.9:1 or whatever? Minimum is not set, only maximum.

Yes but why would you run lower? If i understood things correctly the larger the ratio the more horsepower.

I am saying 16:1 is maximum. Some are arguing, correctly at that, that there will always be some thermal expansion so no one can be exactly within the maximum compression ratio, but I am asking why not take thermal expansion into account (which they do) and design engine in the way that it doesnt go over 16:1?

Running it lower is not forbidden, only maximum is in a rule book.

[f1isgood]

One thing I am thinking…if maximum allowed compression ratio is 16:1, and people argue there is certain amount of expansion that happens to components due to high temperatures, who says you cannot run your engine at lower, at 15.6:1, 15.9:1 or whatever? Minimum is not set, only maximum.

Yes but why would you run lower? If i understood things correctly the larger the ratio the more horsepower.

I am saying 16:1 is maximum. Some are arguing, correctly at that, that there will always be some thermal expansion so no one can be exactly within the maximum compression ratio, but I am asking why not take thermal expansion into account (which they do) and design engine in the way that it doesnt go over 16:1?

Running it lower is not forbidden, only maximum is in a rule book.

Yes but running it lower means you are willingly giving up power. If your base is 15.5 : 1 and it goes to 16 : 1, your maximum is 16:1 and less horsepower than someone whose base is 16:1 and if it goes to 17:1 since higher ratio means more power.

This ratio is measured at ambient temperature. So it is sufficient to pass the test by being 16:1 at that point. So no reason to go lower and willingly give up power.

[brakeboosted]

One thing I am thinking…if maximum allowed compression ratio is 16:1, and people argue there is certain amount of expansion that happens to components due to high temperatures, who says you cannot run your engine at lower, at 15.6:1, 15.9:1 or whatever? Minimum is not set, only maximum.

Lower thermal efficiency at partial loads is one of big reasons why teams chase higher compression. And I guess this is one of the many thigns that's being overlooked with this whole compression saga. Partial load and/or overrun harvesting, the higher thermal efficiency means you harvest more energy for the same unit of fuel, or conversely harvest the same energy for a smaller unit of fuel. So either your average power output is higher or your race fuel load is less. Either way over a race distance this could be worth much more than over a single lap. Which is why I believe its grabbed so much attention. Their gains are obviously dependent on how much they are raising the compression by.

[ferkan]

Yes but why would you run lower? If i understood things correctly the larger the ratio the more horsepower.

I am saying 16:1 is maximum. Some are arguing, correctly at that, that there will always be some thermal expansion so no one can be exactly within the maximum compression ratio, but I am asking why not take thermal expansion into account (which they do) and design engine in the way that it doesnt go over 16:1?

Running it lower is not forbidden, only maximum is in a rule book.

Yes but running it lower means you are willingly giving up power. If your base is 15.5 : 1 and it goes to 16 : 1, your maximum is 16:1 and less horsepower than someone whose base is 16:1 and if it goes to 17:1 since higher ratio means more power.

This ratio is measured at ambient temperature. So it is sufficient to pass the test by being 16:1 at that point. So no reason to go lower and willingly give up power.

No, 16:1 is maximum compression ratio and it is measured at ambient temperatures. Every rule has to be fully complient at any given time over race weekend.

I bet you they all could run at exactly 16:1, and since reason for the rule change to 16:1 was easier entry for new manufacturers, cheaper and less complex engines, gaming this rule cannot be considered legal.

In whole honesty, FIA should have never lowered it to 16:1 in the first place because both Mercedes and Ferrari ran at 18:1 in last regs, as did Honda (and they confirmed they needed 4 years to get there).

[Rodak]

Geometric compression ratio and operating compression ratio are different, as valve overlap will alter the ratio; also this is a turbo-charged engine, so pressure in the cylinder is affected by boost levels. These engines will not be operating at a 16:1 compression ratio even if that is the geometric ambient number.

[FittingMechanics]

No, 16:1 is maximum compression ratio and it is measured at ambient temperatures. Every rule has to be fully complient at any given time over race weekend.

I bet you they all could run at exactly 16:1, and since reason for the rule change to 16:1 was easier entry for new manufacturers, cheaper and less complex engines, gaming this rule cannot be considered legal.

In whole honesty, FIA should have never lowered it to 16:1 in the first place because both Mercedes and Ferrari ran at 18:1 in last regs, as did Honda (and they confirmed they needed 4 years to get there).

You could make an engine that is always at or under 16:1, but it is likely none of the engines satisfy this rule, especially as it was always measured at ambient and specified that the test is at ambient.

They can make a clarification and ask for changes for 2027, that seems reasonable.

[AR3-GP]

Today there was an outbreak of propaganda being posted by Italian media sources for reasons...
AMUS is also useless without Michael Schmidt. None of the sources being parroted are credible. Stop losing your minds over planted bs stories.

[dialtone]

Today there was an outbreak of propaganda being posted by Italian media sources for reasons...
AMUS is also useless without Michael Schmidt. None of the sources being parroted are credible. Stop losing your minds over planted bs stories.

Is your issue the 1cc chamber or that redbull switched sides (from autoracer and not nunes)?

[PlatinumZealot]

This is how the "1.0 cc" works. And it is very sneamy. You guys let me know if you see anything illegal:

A cylindrical chamber in the cylinder head open to the combustion chamber has a conical plug inserted though it's central axis. This conical plug is essentially a heat activated valve that leaves a very narrow annulus between the chamber walls and the valve seat. The plug is made of a higher thermal expansion material than the head. It doesn't have to be any fancy alloy. The cylinder head could be steel and the plug aluminum for example. At room temperature the annulus is open. Only a tiny gap in the annulus is needed for air to pass through during the compression test. This gap could be a "leak" of microns wide. The supposed cylinder volume is in it's highest form here.

Then, as the engine heats up, the annular conical plug expands, creating perfect metal to metal seal, and the annulus no longer exists. That "1 cc" is now sealed off from the cylinder volume and higher compression ratio is achieved.


That said, this trick is easy to pull off and will be easily copied by manufacturers if the FIA passes it as legal.