2025/2026 Hybrid Powerunit speculation

[Zynerji]

Yet, the sportscar world championship was successfully killed, when an engine that no-one wanted to use was forced.

Bad ideas will have consequences.

Such as "setting rules in stone" that no-one wants to compete by. You can't just ignore what potential competitors want.

The human nature will always bias the teams decision making when it comes to rules, so they should have zero part in it.

The 200 IQ play is to set the rules in stone, then compromise slightly after the initial feather ruffle... This works in business every single day, all over the world.

The teams will compete if you have a Formula, prize purse, and enough exposure to drive sponsorship. They may cry about change that doesn't benefit them, but they will get over it.

And yes, if the stone- set idea is bad, it will fail... As it should.

The world is not changed by reasonable men.

[wogx]

Two-stroke engines & eco-fuel: F1 aims to be greener than Formula E

Formula 1's plan for green and noisy engines: two-stroke hybrids, running on synthetic fuel

https://www.motorsportmagazine.com/arti ... -formula-e

[vorticism]

Mentions opposed piston designs as well, although I'm not sure if this is best for the application. Twin crank (save weight on valvetrain but gain it back with extra crank and power carrying idler gears) or doubled up long connecting rods (might limit engine speed)?

This was from 2020 though; the FIA article was from this year and mentions high revving V6s. The 'attracting new manufacturers' part leads me to believe it won't be anything too off the wall.

[gruntguru]

When designing a high efficiency, high speed two stroke, opposed piston and uniflow scavenging is a front running architecture.

[vorticism]

Do you think road car manufacturers would go that way? FIA pushes for road relevance and I take it this means conventional engine architectures.

[johnny comelately]

When designing a high efficiency, high speed two stroke, opposed piston and uniflow scavenging is a front running architecture.

Noooooo
in my opinion
reasons later

[johnny comelately]

Do you think road car manufacturers would go that way? FIA pushes for road relevance and I take it this means conventional engine architectures.

hopefully not limited to conventional, why limit any thinking
that is why the F1 engine is so important, it has taken IC engines to another planet in my way of thinking.
and for tech transfer, TJI is now in Maserati and some Hondas???

[J.A.W.]

Do you think road car manufacturers would go that way? FIA pushes for road relevance and I take it this means conventional engine architectures.

Yeah, best take that FIA claim as mere platitude/propaganda palliative as 'green-washing',
since it has never panned out that way in reality/real-time.

With ICE being demonised by political policies in favour of EV, a more radical approach is
IMO warranted, esp' as the money men of F1 still want the 'BIG SHOW' to roll on...

[J.A.W.]

Bad ideas will have consequences.

I stopped watching WEC when Audi showed up with Diesel engines - Diesel's belong in Semi-trucks, tractors and large commercial vehicles, not in race cars and passenger cars, IMHO. It's not that I dont like the engines, it's the toxic cancer causing by-products they emit that I dislike (plus they are not much fun to drive unless torque is all you care about).

But that is just your opinion. I really like that low rumble, combined with the insane visible acceleration from the onboards. Still at the time we had Porsche V4 and Toyota and LMP2 high rev na engines.

Recall that old line: "That's not a knife... This is a KNIFE!" ?

How's this for filthy ol' Detroit Diesels 'under the pump', with 2-stroke urgency & that rumbling growl..

[Zynerji]

Do you think road car manufacturers would go that way? FIA pushes for road relevance and I take it this means conventional engine architectures.

Yeah, best take that FIA claim as mere platitude/propaganda palliative as 'green-washing',
since it has never panned out that way in reality/real-time.

With ICE being demonised by political policies in favour of EV, a more radical approach is
IMO warranted, esp' as the money men of F1 still want the 'BIG SHOW' to roll on...

One has to wonder if, in the current environment, that an unconventional ICE that is road-irrelevant might not just be the best marketing possible. Set it aside as a bespoke exercise, instead of giving the illusion that these are made to keep ICE relevant forever by being touted as the engine of the future.

Give it a "Historical" exemption to move into a past-tense mindframe. Could get a lot of pressure off the sport.

[J.A.W.]

Yeah, or even a 'high-tech' sporting exposition exemption on those grounds, kind of
akin to boxing, fundamentally brutal & anti-social, but visceral for vicarious thrills...

[johnny comelately]

When designing a high efficiency, high speed two stroke, opposed piston and uniflow scavenging is a front running architecture.

As an example, do you mean like the Achates engine?
opposed piston engines have a rapid pressure drop, making the number of cylinders important if power/torque continuity is important. Is there a relatively high exposed area for heat loss (depending on bore stroke ratio)

My reasoning against 2 strokes is this (as mentioned before)
The oil burning is irrelevant because as with DD and Achates you can oil them like a 4 stroke.
But the limited duration is a major problem
You can 1D from gaga land if you want and give as much VE as is possible (like electric supercharging) but 120 degrees duration or thereabouts is not enough. And injection effectiveness is compromised from this as well, although using 2 injectors (port/direct) would part solve this.
You can view this challenge from a VE air point or as a fuel burn success point which can make 2 strokes a little more acceptable.
all this can lead to compromises in bore stroke ratios too, depending on application.

[vorticism]

When designing a high efficiency, high speed two stroke, opposed piston and uniflow scavenging is a front running architecture.

Without valves I'd assume a very high operating speed could be possible. Up til 2009, were engine builders limited more by piston speed or valve speed? Combined with double the exhaust pulse frequency they could make for an unreal sound. Although need to keep the cylinder count up as well, if I'm making a point about sound. So, how about a 20k RPM twin row six cylinder Deltic arrangement providing a 2k Hz wail (V10s were around 1.5k Hz). Or a three row nine cylinder affair at 3k Hz.

A deltic triangle might not be to bad for structural integrity either. The V engines are already practically a triangle with their mounting bolt patterns. And cram the MGUK right in the middle of the triangle if we're to be doing electric assist.

[gruntguru]

When designing a high efficiency, high speed two stroke, opposed piston and uniflow scavenging is a front running architecture.

As an example, do you mean like the Achates engine?
opposed piston engines have a rapid pressure drop, making the number of cylinders important if power/torque continuity is important. Is there a relatively high exposed area for heat loss (depending on bore stroke ratio)

Relatively low. There is no cylinder head.

My reasoning against 2 strokes is this (as mentioned before)
The oil burning is irrelevant because as with DD and Achates you can oil them like a 4 stroke.
But the limited duration is a major problem
You can 1D from gaga land if you want and give as much VE as is possible (like electric supercharging) but 120 degrees duration or thereabouts is not enough.

120* is 33.3% of the cycle. 4 strokes manage less than 25%.
Geometric compression and expansion ratios can still be set very high although it doesn't matter when turbocharged because a lot of additional compression and expansion is done externally. OP uniflow can have different CR and ER BTW.

[johnny comelately]

When designing a high efficiency, high speed two stroke, opposed piston and uniflow scavenging is a front running architecture.

As an example, do you mean like the Achates engine?
opposed piston engines have a rapid pressure drop, making the number of cylinders important if power/torque continuity is important. Is there a relatively high exposed area for heat loss (depending on bore stroke ratio)

Relatively low. There is no cylinder head.
BUT THERE IS A HUGE AMOUNT OF CYLINDER WALL EXPOSED.

My reasoning against 2 strokes is this (as mentioned before)
The oil burning is irrelevant because as with DD and Achates you can oil them like a 4 stroke.
But the limited duration is a major problem
You can 1D from gaga land if you want and give as much VE as is possible (like electric supercharging) but 120 degrees duration or thereabouts is not enough.

120* is 33.3% of the cycle. 4 strokes manage less than 25%.
IT DOESNT MATTER ABOUT THE PERCENTAGES AS THEY ARE RELATIVE, BUT IT DOES MATTER FOR GAS EXCHANGE AND COMPRESSION, FUELING HOMOGENY (IS THAT A WORD) ETC
Geometric compression and expansion ratios can still be set very high although it doesn't matter when turbocharged because a lot of additional compression and expansion is done externally. OP uniflow can have different CR and ER BTW.

THIS IS JUST MY OPINION