2026 Drama: Alleged engine loophole

[SharkY]

It seems like a weird thing if FIA just lets it go. There is a hard limit of compression ratio in the regulations and it should be enforced.
It feels similar to the Ferrari fuel flow trick, where they took advantage of the measurements to bypass the maximum limit.
Given how keen they are to introduce mid-season or pre-season changes to testing, I don't see why engines should be exempt from this. Either run the test with hot air or specify a maximum thermal expansion between the piston pin and the piston top and let the teams work on the engines to comply.

On the other hand, why wasn't it an issue before? Is 18:1 such an ideal compression ratio, that teams didn't chase to exploit this?

[dialtone]

This is BAD NEWS for all the other teams. At least Red Bull are with it, so we won't have another Merc only season. Fantastic work from Merc and Red Bull. Very very clever engineering. Well done. That is all Red Bull and Merc need for that extra .5 seconds to qualify at the top every race, and always have race pace advantage. This is an enormous development. Other engine manufacturers will not be able to catch up till it is far, far too late for 2026. Peace out Fred! lol.

Such hypocrisy.

Do i need to search what you said about ferrari engine in 2019?

[AR3-GP]

On the other hand, why wasn't it an issue before? Is 18:1 such an ideal compression ratio, that teams didn't chase to exploit this?

There's probably a practical limit around 18:1 for these engines. Thermal efficiency increases but the gains become less and less at higher ratios. That comes from the theory, but you also need stronger pistons and a stronger crankshaft for higher compression ratios. That makes the rotating parts of the engine heavier (bad). You start to eat into the theoretical gains once the engineering required to operate at higher compression ratios is taken into account.

[sucof]

Well, the FIA can cap max horsepower.
They can not measure compression on the fly, but they can surely measure power from the engine. If the alleged gains by the loophole is there, they can set a max power from all the engines till they either comply with the intention of the rules, or the other teams catch up.

It is very interesting how opposing teams found this out. Kinda just as interesting as the loophole itself

[Tommy Cookers]

.... the FIA can cap max horsepower.

... as interesting as the loophole itself

capping max horsepower (in a fuel rate limit formula) is capping ICE efficiency (in an efficiency formula)

there is no loophole
eg cylinders expand in running - the conceptual 1600 cc limit is breached before the car leaves the pit
but it is compliant with the 1600cc limit when checked by the mandated inspection


arguments eg against 18:1 ?
conflicts with valves
Otto cycle efficiency impaired by thermal dissociation (CO2 becomes CO & reverts to CO2 too late in the expansion)
but remember these are Miller cycle engines - the 18:1 is for the expansion not the compression

[MV8]

If they are doing tricks with thermal expansion in parts of the piston (I'm assuming this, I don't really know), would it lead to fatigue problems (more than existing rn)? resulting (maybe) in reliability problems?

It is very interesting how opposing teams found this out. Kinda just as interesting as the loophole itself

Some media are reporting that someone from Mercedes leaked it.

(https://x.com/MercedesF1_Hub/status/2002314574943445449)

[sucof]

.... the FIA can cap max horsepower.

... as interesting as the loophole itself

capping max horsepower (in a fuel rate limit formula) is capping ICE efficiency (in an efficiency formula)

Sorry but this is not an argument even.
Like any part of your argument is written in diamonds by god itself...
The FIA can do whatever they want, including the teams.
The FIA have repeatedly said, when there will be huge differences between engines, they will act.
And regardless of this, they still can. They just have to want it.

If the teams in question have a brain, they will probably limit their engines so that it will not be deemed too much stronger than the competition, so they will retain some benefit. If their engine will be deemed too much more powerful the FIA will probably step in.

[sucof]

If they are doing tricks with thermal expansion in parts of the piston (I'm assuming this, I don't really know), would it lead to fatigue problems (more than existing rn)? resulting (maybe) in reliability problems?

It is very interesting how opposing teams found this out. Kinda just as interesting as the loophole itself

Some media are reporting that someone from Mercedes leaked it.

(https://x.com/MercedesF1_Hub/status/2002314574943445449)

Thanks, very interesting! Also seems to be a bad situation... for the engineer, because the info got out, so I presume everyone will know who he is.

[jumpingfish]

A couple of weeks ago I read that Marcin Budkowski (former Alpine director) said some things about the 2026 engines. Among other things there was a rumor that Ferrari has problems with materials - they’ve chosen something for building the engine pistons which has turned out to be a mistake and they now have to change the design. Could this mean that Ferrari trying to increase compression ratio?

[Badger]

Reading a bit between the lines it seems to me like the FIA is reluctant to do anything about this, they keep reiterating that the test is done under ambient temperatures. https://www.the-race.com/formula-1/tric ... ntroversy/

An FIA spokesperson told The Race: “The regulations clearly define the maximum compression ratio and the method for measuring it, which is based on static conditions at ambient temperature.

“This procedure has remained unchanged despite the reduction in the permitted ratio for 2026.”

However, the issue may have cropped up ahead of 2026 because manufacturers have realised, amid the change of characteristics with the 2026 regulations, that there are grounds to seek advantage from chasing a higher compression ratio than what is laid down in the rules.

And while it is well known that thermal expansion of engine components is a natural phenomenon, there is no measurement laid down in the rules that dictates what is an acceptable level for this to happen.

The FIA has suggested that procedures could be changed, or even the regulations revised, if the matter blows up in the early stages of the season.

The FIA spokesperson added: “It’s true that thermal expansion can influence dimensions at operating temperature, but the current rules do not currently require measurement under hot conditions.

“That said, the topic has been and is still being discussed within technical forums with the PUMs [power unit manufacturers], as the new limit naturally raises questions about interpretation and compliance.

“The FIA continuously reviews such matters to ensure fairness and clarity, and if necessary, adjustments to the regulations or measurement procedures can be considered for the future.”

With F1’s engines homologated, and designs having been locked down long ago, any change to the rules that requires new internals could be incredibly complicated to achieve – especially in a short time frame.

Any change on this front would require a complete redesign to the internals of the ICE, that's a big job and it's way too late for that if the FIA hasn't raised red flags earlier than this. Also consider the implications on fuel, each manufacturer's fuel blend will be designed with the compression ratio in mind to minimise knocking.

This is standard F1, some teams saw the change in compression ratio and didn't think too much about it, others realised it was an opportunity.

[proteus]

.... the FIA can cap max horsepower.

... as interesting as the loophole itself

capping max horsepower (in a fuel rate limit formula) is capping ICE efficiency (in an efficiency formula)

Sorry but this is not an argument even.
Like any part of your argument is written in diamonds by god itself...
The FIA can do whatever they want, including the teams.
The FIA have repeatedly said, when there will be huge differences between engines, they will act.
And regardless of this, they still can. They just have to want it.

If the teams in question have a brain, they will probably limit their engines so that it will not be deemed too much stronger than the competition, so they will retain some benefit. If their engine will be deemed too much more powerful the FIA will probably step in.

If they step in and limit the engines, then they should simply close the doors and dispand the sport. In what universe is this even considered as good and competitive?

The best thing is that at every race they start to give away participation medals to the drivers instead of podiums and points. Everyone is a winner....

Ever since they decided they want to run a budget racing series (even before official budget cap) the whole sport started to look like a kids show. This will take it to a whole new level of that.

Ban the engine suppliers then, chuck in a generic engine. There is no use to have suppliers in the sport if they are basically forced to curb themself, or being handicaped by the governing body.

[AR3-GP]

A couple of weeks ago I read that Marcin Budkowski (former Alpine director) said some things about the 2026 engines. Among other things there was a rumor that Ferrari has problems with materials - they’ve chosen something for building the engine pistons which has turned out to be a mistake and they now have to change the design. Could this mean that Ferrari trying to increase compression ratio?

It was suggested that Ferrari attempted to design a 3D printed cylinder head (allows for better cooling of the head which allows higher operating temp and thus greater thermal efficiency) but it was too unreliable. That would have been the “materials problem”.

[Emag]

I made this comment in the RedBull team thread, but I think here it's more appropriate :

I don’t really know engine hardware enough to understand the implied consequences. So, if we assume FIA decides they don’t agree with this, would Mercedes and RBPT be heavily compromised like what happened to Ferrari’s 2020 power units after 2019?

Or is this more of a “quick patch” that just switches off this presumed advantage and they can go ahead run with the same designs?

[dialtone]

I made this comment in the RedBull team thread, but I think here it's more appropriate :

I don’t really know engine hardware enough to understand the implied consequences. So, if we assume FIA decides they don’t agree with this, would Mercedes and RBPT be heavily compromised like what happened to Ferrari’s 2020 power units after 2019?

Or is this more of a “quick patch” that just switches off this presumed advantage and they can go ahead run with the same designs?

They can quick patch and lose some performance, nowhere near the penalty that Ferrari got in 2019, they had to redesign the engine from scratch, particularly the hybrid part.

A fuel for a higher compression can be reused in lower compression (you can use premium fuel in engines that don’t need it, bit of a waste but works fine), and they would need to make changes to the piston to not reach that higher compression, depending on the trick it could be quick or not, in all likelihood once again designing a standard piston/cylinder is probably something they already have done so they can probably just switch to that design. They certainly have A/B tested their trick against the common design to validate it.

It will be worse than if they started with that design from the start but nothing really terrible.

[selvam_e2002]

so we ill have teams MEC and the engine used by the team like, Williams, Mclaren, Renault along with RB will be in good position compared to Audi and Honda..... I really feel for Alonso, it is never worked out for him with Honda. I am expecting GP2 again from him.....