2025/2026 Hybrid Powerunit speculation

[Tommy Cookers]

....I haven't even gotten to the point of asking about using nitro-methane in them... Would 100L get a car to the end??

no
nitromethane is a very poor fuel compared to the conventional fuel

nitro has over twice the stoichiometric mass-specific energy ....
so makes over twice the power for a given air consumption ie from a given engine it gets over twice the power ....
but has about one eighth of the mass-specific energy so that power needs about eight times as much weight of nitro fuel

ie equal power might come from halving the engine size but would need 3 - 4 times as much weight of nitro fuel and ....

(nitromethane's own oxygen accessed by rich AFR) would allow an even smaller engine but need a disproportionate fuel load
such a semi-rocket piston engine might not last 5 races

[Zynerji]

....I haven't even gotten to the point of asking about using nitro-methane in them... Would 100L get a car to the end??

no
nitromethane is a very poor fuel compared to the conventional fuel

nitro has over twice the stoichiometric mass-specific energy ....
so makes over twice the power for a given air consumption ie from a given engine it gets over twice the power ....
but has about one eighth of the mass-specific energy so that power needs about eight times as much weight of nitro fuel

ie equal power might come from halving the engine size but would need 3 - 4 times as much weight of nitro fuel and ....

(nitromethane's own oxygen accessed by rich AFR) would allow an even smaller engine but need a disproportionate fuel load
such a semi-rocket piston engine might not last 5 races

As always, I love your responses!

Thank you!

[taperoo2k]

Is anyone actually happy with the expected 2026 engines?

I'm of the mind currently that it could seriously just be best to move to a 1.6l v6 N/A-DI 2 stroke (v12 sound, and high RPM feel) with the current (mostly) block architecture and delete the turbo. Keeping a 240kw KERS to torque fill would seem preferable for economy and drivability. Then 2008 sized cars, and I'm in.

In an ideal world with synthetic fuels you'd go back to the V10 or V12 screamers. But that is of no interest to the manufacturers. F1 is a testing ground for Hybrid technology amongst other elements of the PU alongside being a marketing exercise.

What I see and hear for 2026 currently simply does not feel very impressive, and that is hugely disappoint to this long-time fan.

It's either going to be a clown car show in terms of the racing or it might actually be exciting. It's hard to say at this point. Max wasn't very impressed with the simulator runs with the RB PU a couple of years ago now. Things have likely moved on since then.

When you look at the technical challenges the manufacturers face for 2026, it is quite interesting. You have to wonder how much of an impact the synthetic fuels are going to have on the respective PU's performance levels.

[DenBommer]

Always great videos and analyses from Scarbs. And personally, it’s also nice to hear that I’m not the only one who sees it as a missed opportunity for F1 not to have regenerative braking on the front wheels—at the very least, to recover some energy.

[mzso]

I'm unclear how development will work, perhaps I wasn't paying attention.
They talk about submitting for homologation in a Honda article. So I guess the PUs will be instantly frozen? For how long?

Potentially another disaster in the making. As it was in 2014 where the development was limited by some point system. And even that they revoked seeing how things turned out. And even after it took other manufacturers to around 2020 to reach mercedes. (Not counting Ferrari's cheaty engines.)

[mzso]

Always great videos and analyses from Scarbs. And personally, it’s also nice to hear that I’m not the only one who sees it as a missed opportunity for F1 not to have regenerative braking on the front wheels—at the very least, to recover some energy.

Yeah, the cartel shouldn't have a say in the regulations.

[ENGINE TUNER]

I'm unclear how development will work, perhaps I wasn't paying attention.
They talk about submitting for homologation in a Honda article. So I guess the PUs will be instantly frozen? For how long?

Potentially another disaster in the making. As it was in 2014 where the development was limited by some point system. And even that they revoked seeing how things turned out. And even after it took other manufacturers to around 2020 to reach mercedes. (Not counting Ferrari's cheaty engines.)

You are incorrect, the token system worked very well. It stopped the manufacturers from making small revisions, and forced them to focus on both financial and performance efficiency. Ferrari made huge changes for 2015(and still didn't use all their tokens) and were almost up to par with Mercedes at that point, but I do think that is when they began fuel cheating. The token system allowed unlimited reliability changes yet Renault and Honda kept having problems well into 2018, so not a token problem. The token system did almost exactly what it was intended to do. Merc were just better than everyone else. The situation with engine parity was about the same as it was with the 2.4Lv8s, Merc and Ferrari the best. Renault and the rest struggling.

[wuzak]

I'm unclear how development will work, perhaps I wasn't paying attention.
They talk about submitting for homologation in a Honda article. So I guess the PUs will be instantly frozen? For how long?

In Appendix C4, Table 1 there is a list of PU components with the upgrade schedule.

For instance, item 4 is: Main ICE assembly comprising Combustion chamber surface and pre-chamber detail within cylinder heads, piston, connecting rod, camshaft lobe profiles, intake and exhaust ports, Valvegear air spring sub-assemblies.

The homologation schedule for that item is 2026, 2027 and 2029. No new homologations for 2028 and 2030.

However, there is a category "Additional Development and Upgrade Opportunities". Manufacturers will apply for his if they are behind, and if they are granted this status they will be able to upgrade that component in years where upgrades are not available. Not all items allow that, though.

[wuzak]

[piast9]

Well, I don't get it. I undestand and I think it is a good idea to gradually taper down the electric power when the battery is running out to avoid being rear ended. But leave everyting else, please! Nobody says that if you are permitted to use 350 kW of electric drive then you HAVE TO do it. Let the driver and team manage the energy around the lap. What's wrong with that?

[mzso]

Well, I don't get it. I undestand and I think it is a good idea to gradually taper down the electric power when the battery is running out to avoid being rear ended. But leave everyting else, please! Nobody says that if you are permitted to use 350 kW of electric drive then you HAVE TO do it. Let the driver and team manage the energy around the lap. What's wrong with that?

It's probably fastest to do it in a dangerous way.

[diffuser]

I'm unclear how development will work, perhaps I wasn't paying attention.
They talk about submitting for homologation in a Honda article. So I guess the PUs will be instantly frozen? For how long?

Potentially another disaster in the making. As it was in 2014 where the development was limited by some point system. And even that they revoked seeing how things turned out. And even after it took other manufacturers to around 2020 to reach mercedes. (Not counting Ferrari's cheaty engines.)

You are incorrect, the token system worked very well. It stopped the manufacturers from making small revisions, and forced them to focus on both financial and performance efficiency. Ferrari made huge changes for 2015(and still didn't use all their tokens) and were almost up to par with Mercedes at that point, but I do think that is when they began fuel cheating. The token system allowed unlimited reliability changes yet Renault and Honda kept having problems well into 2018, so not a token problem. The token system did almost exactly what it was intended to do. Merc were just better than everyone else. The situation with engine parity was about the same as it was with the 2.4Lv8s, Merc and Ferrari the best. Renault and the rest struggling.

The token system was Honda's biggest impediment. Honda complained so much about it. The biggest problem was it limited the number of parts on the PU you could update at once but all the parts in a PU work together. So. If you're limited to only 2 parts and you want to modify your heads but you can only modify the exhaust or the intake but not both.

Once they announced the demise of the token system, Honda completely redesigned the whole PU.

[wuzak]

This was taken from the Autosport forums:

A quote of Kimi Antonelli about the 2026 regulations:

“We will have much more power from the electric, but with the same battery capacity. Also looking at simulations, we noticed the graph and the battery will go from full charge to nothing on a straight and so this will mean that on circuits like Monza the electric could finish very quickly, finding yourself with only the 500 horsepower of the internal combustion engine. This means that the car will slow down on the straight, but we have seen that we as drivers can also make a lot of difference in how we manage the battery. Especially where there are curves one after the other we will also have to not go full on the accelerator to save more battery and have more for the straight. It is very complicated, so much so that even the FIA ​​is continuing to apply changes because they have realized that it is not the best of the regulations. We certainly do not yet know what it will be like in the end, but we drivers have already seen that with driving we can really make a lot of difference“. In addition to the important changes related to the engine, the aerodynamics will also bring important changes: "In the end, the car itself will return a bit to how it was before this regulation, so it will no longer be in ground effect, it will return to the flat bottom. And so let's say it will be a bit more old-fashioned. I have to say that the car itself will be fun to drive, the only problem is that with this battery factor there will be more things to take into consideration. You will definitely have a lot more thrust initially, in fact we will reach the top speed much earlier than now. In Monza we did some simulations and the top speed will probably be immediately after the finish line. So it will be really different and in fact as a team we were thinking of bringing a simulator to the track, obviously a small one, not the ones we use in the factory, so that we can also mentally prepare ourselves, because it will require a completely different driving style compared to what we are used to now".

The source of the quote was https://x.com/Auto_Racer_it/status/1922716840913936722

Doesn't sound too encouraging.

Especially since the Mercedes is supposedly the strongest PU for next year.

[wuzak]

The first 2026 car test will be held in private.

https://www.the-race.com/formula-1/firs ... s-private/

[Juzh]

Hey wuzak, have you noticed this update to engine regs (post from reddit highlighting PU changes)
https://old.reddit.com/r/formula1/comme ... erational/

There is a limit on energy harvesting of 8.5Mj per lap. At some events this may be reduced to 8Mj where the FIA determines that you can't really harvest more than 8Mj per lap.
This limit may be further reduced to no less than 5MJ for Sprint Qualifying and Qualifying sessions at Competitions where the FIA determines that the harvesting strategies required to achieve the above limit are excessive, subject to the conditions specified in Article B7.2.

Also:

There is a total power reduction limit of 450kW maximum and the resulting electrical DC power of the ERS-K must remain above -100kW(i.e. 350kW deployment to 100kW harvest = 450kW power reduction)
These limits are changed respectively to 600kW and -250kW for the Sprint Qualifying and Qualifying sessions.

So more regen will be allowed in quali, but not during the race. I expect this is because -250kw is a serious amount of decel while under full throttle and it could be seen as a sort of brake check and potentially dangerous.