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Re: 2025/2026 Hybrid Powerunit speculation
Posted: 18 Jan 2026, 02:31
by gearboxtrouble
wuzak wrote: ↑18 Jan 2026, 02:21
gearboxtrouble wrote: ↑17 Jan 2026, 23:56
Hoffman900 wrote: ↑17 Jan 2026, 22:44
Despite what they say, with the cylinder deactivation strategies and other harvesting strategies, there are psuedo traction control strategies at play and have been since 2014.
Indeed. That's what I think makes this even more feasible now because you have a 350KW MGUK providing negative torque that can be varied on demand when it's "harvesting". Instead of the brute force approach of deactivation you now have a fine grained approach of harvesting during the acceleration phase in certain conditions in a way that's a lot closer to real traction control. Given the torque of these new PUs, this could be very important for everything from tire wear to performance.
There is a rule (or rules) governing the ouput of the PU based on the driver input.
For example, the power output cannot be reduced (ie MGUK harvesting increased) unless the driver reduces demand (there are exceptions based on ERS parameters - but that involves deployment, not recovery).
Wouldn’t that depend on where that power is measured? I could see engine output rising with throttle but MGUK harvesting lowering wheel torque based on parameters programmed into the throttle maps and harvesting algo. Would seem that the rules offer enough space for creative interpretation in this area.
Re: 2025/2026 Hybrid Powerunit speculation
Posted: 18 Jan 2026, 05:00
by FW17
How likely are we to see 450KW~600hp from the engine 54% eff at the start of 2026 season
I think it will be somewhere between 570 and 600 hp from ICE
Re: 2025/2026 Hybrid Powerunit speculation
Posted: 18 Jan 2026, 05:44
by wuzak
FW17 wrote: ↑18 Jan 2026, 05:00
How likely are we to see 450KW~600hp from the engine 54% eff at the start of 2026 season
Unlikely, IMO.
I think they'll be 420-430kW, around 50-52% TE.
Re: 2025/2026 Hybrid Powerunit speculation
Posted: 18 Jan 2026, 07:22
by FW17
wuzak wrote: ↑18 Jan 2026, 05:44
FW17 wrote: ↑18 Jan 2026, 05:00
How likely are we to see 450KW~600hp from the engine 54% eff at the start of 2026 season
Unlikely, IMO.
I think they'll be 420-430kW, around 50-52% TE.
The last engines hit 51% at start of 2022 season when it was frozen
Re: 2025/2026 Hybrid Powerunit speculation
Posted: 18 Jan 2026, 08:12
by wuzak
FW17 wrote: ↑18 Jan 2026, 07:22
wuzak wrote: ↑18 Jan 2026, 05:44
FW17 wrote: ↑18 Jan 2026, 05:00
How likely are we to see 450KW~600hp from the engine 54% eff at the start of 2026 season
Unlikely, IMO.
I think they'll be 420-430kW, around 50-52% TE.
The last engines hit 51% at start of 2022 season when it was frozen
With turbo-compounding?
Re: 2025/2026 Hybrid Powerunit speculation
Posted: 18 Jan 2026, 08:21
by saviour stivala
FW17 wrote: ↑18 Jan 2026, 07:22
wuzak wrote: ↑18 Jan 2026, 05:44
FW17 wrote: ↑18 Jan 2026, 05:00
How likely are we to see 450KW~600hp from the engine 54% eff at the start of 2026 season
Unlikely, IMO.
I think they'll be 420-430kW, around 50-52% TE.
The last engines hit 51% at start of 2022 season when it was frozen
If you mean '600HP' from the ICE, That in my opinion is likely, Also in my opinion the new power unit will take-off with a better thermal efficiency than the previous best of power unit left of, and progress to maybe 3-4 percentage points more.
Re: 2025/2026 Hybrid Powerunit speculation
Posted: 18 Jan 2026, 08:46
by FW17
wuzak wrote: ↑18 Jan 2026, 08:12
FW17 wrote: ↑18 Jan 2026, 07:22
wuzak wrote: ↑18 Jan 2026, 05:44
Unlikely, IMO.
I think they'll be 420-430kW, around 50-52% TE.
The last engines hit 51% at start of 2022 season when it was frozen
With turbo-compounding?
What compounding?
Re: 2025/2026 Hybrid Powerunit speculation
Posted: 18 Jan 2026, 09:25
by wuzak
FW17 wrote: ↑18 Jan 2026, 08:46
wuzak wrote: ↑18 Jan 2026, 08:12
FW17 wrote: ↑18 Jan 2026, 07:22
The last engines hit 51% at start of 2022 season when it was frozen
With turbo-compounding?
What compounding?
The maximum efficiency was when the MGUH fed power directly to the MGUK.
This is turbo-compounding.
Re: 2025/2026 Hybrid Powerunit speculation
Posted: 18 Jan 2026, 09:49
by djos
wuzak wrote: ↑18 Jan 2026, 09:25
FW17 wrote: ↑18 Jan 2026, 08:46
wuzak wrote: ↑18 Jan 2026, 08:12
With turbo-compounding?
What compounding?
The maximum efficiency was when the MGUH fed power directly to the MGUK.
This is turbo-compounding.
In not sure you understand the definition of the word compounding, you can’t compound a turbo without a second turbine!
Re: 2025/2026 Hybrid Powerunit speculation
Posted: 18 Jan 2026, 09:52
by FW17
wuzak wrote: ↑18 Jan 2026, 09:25
FW17 wrote: ↑18 Jan 2026, 08:46
wuzak wrote: ↑18 Jan 2026, 08:12
With turbo-compounding?
What compounding?
The maximum efficiency was when the MGUH fed power directly to the MGUK.
This is turbo-compounding.
With compounding of MGU H it was 59%
51% was only from ICE
Re: 2025/2026 Hybrid Powerunit speculation
Posted: 18 Jan 2026, 10:00
by wuzak
djos wrote: ↑18 Jan 2026, 09:49
wuzak wrote: ↑18 Jan 2026, 09:25
FW17 wrote: ↑18 Jan 2026, 08:46
What compounding?
The maximum efficiency was when the MGUH fed power directly to the MGUK.
This is turbo-compounding.
In not sure you understand the definition of the word compounding, you can’t compound a turbo without a second turbine!
Turbo-compounding is where a turbine feeds power back to the crankshaft of an engine to enhance ouput.
Like the Wright R-3350 turbo-compound engine used in the Douglas DC-7 and some versions of the Lockheed Constellation.
The Wright R-3350 was supercharged, but not turbocharged. It had 3 "power recovery turbines" connected to the crankshaft.
A compound turbo setup uses two, or more, I guess, turbos.
Re: 2025/2026 Hybrid Powerunit speculation
Posted: 18 Jan 2026, 10:03
by wuzak
FW17 wrote: ↑18 Jan 2026, 09:52
wuzak wrote: ↑18 Jan 2026, 09:25
FW17 wrote: ↑18 Jan 2026, 08:46
What compounding?
The maximum efficiency was when the MGUH fed power directly to the MGUK.
This is turbo-compounding.
With compounding of MGU H it was 59%
51% was only from ICE
Was it?
Where is the source for that?
Re: 2025/2026 Hybrid Powerunit speculation
Posted: 18 Jan 2026, 10:20
by FW17
wuzak wrote: ↑18 Jan 2026, 10:03
FW17 wrote: ↑18 Jan 2026, 09:52
wuzak wrote: ↑18 Jan 2026, 09:25
The maximum efficiency was when the MGUH fed power directly to the MGUK.
This is turbo-compounding.
With compounding of MGU H it was 59%
51% was only from ICE
Was it?
Where is the source for that?
Dont know the source, but a lot of online chatter on RA621H being 1014hp
which would be close to 59-60%
Re: 2025/2026 Hybrid Powerunit speculation
Posted: 18 Jan 2026, 10:48
by wuzak
FW17 wrote: ↑18 Jan 2026, 10:20
wuzak wrote: ↑18 Jan 2026, 10:03
FW17 wrote: ↑18 Jan 2026, 09:52
With compounding of MGU H it was 59%
51% was only from ICE
Was it?
Where is the source for that?
Dont know the source, but a lot of online chatter on RA621H being 1014hp
which would be close to 59-60%
That'd be with battery assistance.
You can't count battery assistance in teh thermal efficiency calculation.
1014hp = 854hp from ICE.
Which is about 51% TE for the ICE.
Which is what you said.
Turbo-compounding would not give 160hp to the MGUK without battery assistance.
Re: 2025/2026 Hybrid Powerunit speculation
Posted: 18 Jan 2026, 13:19
by BassVirolla
wuzak wrote: ↑18 Jan 2026, 10:00
djos wrote: ↑18 Jan 2026, 09:49
wuzak wrote: ↑18 Jan 2026, 09:25
The maximum efficiency was when the MGUH fed power directly to the MGUK.
This is turbo-compounding.
In not sure you understand the definition of the word compounding, you can’t compound a turbo without a second turbine!
Turbo-compounding is where a turbine feeds power back to the crankshaft of an engine to enhance ouput.
Like the Wright R-3350 turbo-compound engine used in the Douglas DC-7 and some versions of the Lockheed Constellation.
The Wright R-3350 was supercharged, but not turbocharged. It had 3 "power recovery turbines" connected to the crankshaft.
A compound turbo setup uses two, or more, I guess, turbos.
Totally (w)right.
I'd like to note that the MGUH to MGUK is an electrically linked turbo compounding in place of the mechanical link of the Wright PRT.
Sometimes is overlooked (and understated) such electrical compounding link.