spwolf

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Agree! But it has been axed as well, a second gen or a deeper facelift with the same 2.5 found in the Crown... It would be epic.




To my understanding, it’s the GR Yaris engine that’s rated at 250hp, not that H2 ICE powered Corolla...

If a 1900kg, 184hp road going Mirai is only 13sec slower than a Corolla GR based striped out race car with 250hp... I think it’s better no to be launched...

no, you are understanding it wrong. He is saying this Corolla H2 has 250hp, while Mirai has 150hp and if Mirai had 250hp, it would spend same amount of hydrogen, and that H2 is real contender compared to FCEV.

Only 13s slower? That is ages in racing.

You misunderstood the article completely, it is completely opposite - he thinks H2 Corolla is awesome.
 

Will1991

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That’s another issue...

To my knowledge, a ICE and a FC having similar efficiencies is only possible if Toyota found the holly grail for the ICE or if their FC isn’t that good...

Keep in mind, Fuji has 4.5km:
Mirai has 1900kg and a 184ps motor for a (with some time) 180km/h top speed.
That Corolla should be around 1200kg and (supposedly) 250ps using racing tires and suspension.
That's 700kg less and 70ps more for the Corolla... 13sec is nothing... Just from 0-100km/h is 3/4sec difference...
 
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ssun30

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In the article they explained the actual concern is reliability: they want a hydrogen semi-truck to last 2 million km. Fuel cells are far from that goal while ICEs can meet that target quite easily. It seems the H2 ICE program will eventually be commercial use only.

An autonomous truck running 24/7 will do ~1000km a day (~4x the amount a human driver today does). This means it will run 2M km in less than 6 years. A typical diesel truck today already have a lifespan of 1M km over 10 years. For the operator the question then becomes fuel cost vs. maintenance cost. H2 ICE truck uses more fuel but FC truck may need a costly mid-life powertrain replacement.

I hope more people could understand that there is no such thing as a H2 vs. battery debate. Both technologies scale differently: H2 scales up better (commercial) while batteries scale down (passenger) better. I just don't understand why so many people believe it's an either-or situation. BEV semi-trucks won't work just like how H2 passenger cars won't work.
 

ssun30

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did you actually read the whole article?
Don't use Google Translate.

It says the 250PS figure is necessary to achieve that lap time. It was not confirmed by Toyota. That's an estimation by the author.

Also the author claims the ICE has an efficiency of 40% but that's not an official number from Toyota. (For reference the tank-to-wheel efficiency of Mirai 1 is 57% and Mirai 2 is 66%).
[Note however, that Morizo (Akio) was indeed surprised by the thermal efficiency of the H2 ICE that far outperformed their expectations]

He also estimates the H2 ICE can achieve same energy efficiency as FC with hybridization, again without any confirmation.

In summary the author made a lot of assumptions and estimations that are NOT confirmed by Toyota. And clearly he lacks the fundamental understanding of why ICE or any other heat engine is so inefficient compared to FC/batteries.

In the beginning the author said according to multiple interviews, H2 ICE is NOT on Toyota's future energy roadmap. But Morizo (Akio) approved a racing program any way, just to see exactly how well will a H2 ICE work. And it outperformed expectations.

To my knowledge, a ICE and a FC having similar efficiencies is only possible if Toyota found the holly grail for the ICE or if their FC isn’t that good...
Mirai 2's FC is already more efficient than the most efficient heat engine ever made (combined cycle turbines with ~60% efficiency). Electrochemical systems are just more efficient than heat engines period. Anyone with undergraduate thermodynamics course understands that.
 
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ssun30

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My take on the article: so far the H2 GR Corolla program has not demonstrated the feasibility of H2 ICE as part of Toyota's future energy strategy. They remain committed to FC and batteries. That is not to say someone like Akio, who would do anything to preserve the ICE (like how Mazda has to keep the Wankel program alive), will approve a program that leads to some niche civilian product. Or, they could achieve some breakthrough that could make H2 ICE extremely reliable to justify it for heavy commercial vehicles and a military contract.
 

spwolf

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My take on the article: so far the H2 GR Corolla program has not demonstrated the feasibility of H2 ICE as part of Toyota's future energy strategy. They remain committed to FC and batteries. That is not to say someone like Akio, who would do anything to preserve the ICE (like how Mazda has to keep the Wankel program alive), will approve a program that leads to some niche civilian product. Or, they could achieve some breakthrough that could make H2 ICE extremely reliable to justify it for heavy commercial vehicles and a military contract.

Like Will, you are confusing your personal opinion and what is written in the article.
In the article, author writes that H2 is amazing and competitive to FCEV. Period. Google translation works great, there is no ambiguity there at all. It is authors opinion of course, like most articles are.

You can argue that you dont agree with the article, however you can not argue that FCEVs are better than H2 engine based on this article.

On my side, I do not care at all. I am very confident that there will be no hydrogen fuel pump 500km close to me, while I already have hundreds of EV chargers trickled around my city alone and superchargers on my highways. So personally, my future is EV for sure (and my M3P is coming in 30 days or less).

I am just saying that this article can not be used to bash H2 motor when it is about how great it is - and last of all, it seems to be making 250hp, it is very quick. I think you said it would be very underpowered?
 

internalaudit

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In the article they explained the actual concern is reliability: they want a hydrogen semi-truck to last 2 million km. Fuel cells are far from that goal while ICEs can meet that target quite easily. It seems the H2 ICE program will eventually be commercial use only.

An autonomous truck running 24/7 will do ~1000km a day (~4x the amount a human driver today does). This means it will run 2M km in less than 6 years. A typical diesel truck today already have a lifespan of 1M km over 10 years. For the operator the question then becomes fuel cost vs. maintenance cost. H2 ICE truck uses more fuel but FC truck may need a costly mid-life powertrain replacement.

I hope more people could understand that there is no such thing as a H2 vs. battery debate. Both technologies scale differently: H2 scales up better (commercial) while batteries scale down (passenger) better. I just don't understand why so many people believe it's an either-or situation. BEV semi-trucks won't work just like how H2 passenger cars won't work.
so Tesla Semi is BS?
 

Ian Schmidt

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so Tesla Semi is BS?
Tesla Semi hinges on how widespread the battery swap stations are and how well they work. Even if it works perfectly it's still a hack around a fundamental problem with current BEV technology, one that H2 (and diesel, for that matter) don't have.
 

spwolf

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Tesla Semi hinges on how widespread the battery swap stations are and how well they work. Even if it works perfectly it's still a hack around a fundamental problem with current BEV technology, one that H2 (and diesel, for that matter) don't have.

does it really though? Because Volvo trucks in Sweden are charged at 800v/350kwh charging stations if I remember correctly.
 

ssun30

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does it really though? Because Volvo trucks in Sweden are charged at 800v/350kwh charging stations if I remember correctly.
What works in a tiny country like Sweden does not scale well in a huge country like USA.
so Tesla Semi is BS?
It could still be viable before autonomous driving becomes common. Truckers work a limited hours and drive a small distance per day which masks the charging/range problem.
 

ssun30

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I mentioned this in the LC300 thread. The F33A-FTV diesel engine is a 90-degree hot-V with sequential twin-turbo. It's not a diesel version of the V35. It's not hard to imagine what could be an extension of this concept.

The intercooler is tiny and also sits in a hot location which is not a problem for a high-efficiency diesel. But for some higher performance concept they may need to move it somewhere else for better cooling.

hotV.png

sequential.png
 
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carguy420

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I'm kinda disappointed by the 2.4T's power output. Didn't someone here mention that it's going to have more than 300hp?
 

Levi

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shame that we do not have 8GR-FXS in any car lighter than LS/LC. With GS gone, there is a need for IS 500h/RC 500h. But it is mostly interesting for European market with high petrol prices. In North American market most will pay for the better performing V8 for same price, even if less fuel efficient.

I want to see acceleration comparison to 250 km/h or at least 200km/h between GS 450h and new NX 450h+.
 

carguy420

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As is the case with V35, the engine could have different tune for different applications. NX350 is already offering the most power and torque in this segment.
Ok, so we will probably see the 300+hp version in vehicles that are currently using the 3.5L V6? Can't wait for Toyota to release more of the nitty gritty info on this T24A-FTS because it seems like it's even more advanced than the other current DF engines.
 

larryren

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shame that we do not have 8GR-FXS in any car lighter than LS/LC. With GS gone, there is a need for IS 500h/RC 500h. But it is mostly interesting for European market with high petrol prices. In North American market most will pay for the better performing V8 for same price, even if less fuel efficient.

I want to see acceleration comparison to 250 km/h or at least 200km/h between GS 450h and new NX 450h+.
Toyota only put that system on 15th Gen. Crown. 0-100km/h just need 4.7s, but it also weight 1870kg.....
 
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