Will1991

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There is no dedicated ON/OFF AC button like my CT had or the IS. You have to use the remote touch.

I was misinterpreting what you were saying, and I can’t really recall to be honest, but it’s true I’m not seeing it.
 

CRSKTN

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As an engineer, I appreciate technology in cars. But when the "technology" that auto enthusiasts now obsess over is an infotainment screen (and not the engine or transmission), I am thinking that something has gone absolutely wrong.

Does the resolution of the infotainment screen improve driving quality? Does it make the car handle better? Does it improve fuel efficiency? No? So why the obsession with it?

I have the navigation system in my ESh but cannot stand to have the bright screen with constantly moving images in my peripheral vision, so I have set a home screen with dark, static graphics that does not bother me when I am driving. When I am driving, I prefer to be driving, not focusing on an infotainment screen.

Cars have become so refined that for 99% of drivers, the things they directly interact with the most isn't the handling, it's the interface.

Also those systems auto dim and change color schemes for when it's dark. They've thought of this stuff. It's just not the best executed.
 

Will1991

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I don't have any real information, but Lexus is rumored to launch a LS600h, and to me it makes no sense on going back to a 12 year old powertrain which isn't available outside the Century.
To me it should be a upgraded version of the 500h powertrain with more power, and it would be a pretty good IS F with it.

TT V8 shouldn't happen since Lexus is rumored to drop V8's under 90K USD.

TT V6, maybe, but I've read around here that it hasn't been built for bonkers performance...

And we also have next C-AMG going PHEV... Maybe a IS F using a 600h powertrain (upgraded multistage 3.5L V6 already found on current Crown) isn't that farfetched...
 

Gecko

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I believe the new “600h” will be 3.5L TT V6 + next gen hybrid powertrain: ~450hp/500+lb-ft of torque.

It will definitely be in:
Tundra
Land Cruiser
LX
Sequoia

... and probably be in:
LF-1 “600h” if it happens
LS 600h
LC 600h?

“600h” will definitely not be 5.0L V8 + hybrid, as it was before.
 

Will1991

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I find a bit intriguing a turbo hybrid from Toyota, running a Atkinson cycle makes for low exhaust pressure which doesn't work very well for turbos... I even don't know if turbo-ing a Atkinson will not decrease efficiency on low-medium engine loads (were the engine spends most of the time)... Unless they return to a Otto cycle, but then the thermal efficiency is going to suffer...

Both Atkinson or Otto turbo hybrid would have a problem, hybrids have a lot of moments that go directly from engine off to high load, turbo lag and eCVT "rubber" effect... Acceleration feel should be a concern...

Another option would be a Miller cycle, but that requires a supercharger, reducing some efficiency from parasitic losses...

From my point of view, maybe a more powerful battery and electric engine would yield a better result overall...
 

internalaudit

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I find a bit intriguing a turbo hybrid from Toyota, running a Atkinson cycle makes for low exhaust pressure which doesn't work very well for turbos... I even don't know if turbo-ing a Atkinson will not decrease efficiency on low-medium engine loads (were the engine spends most of the time)... Unless they return to a Otto cycle, but then the thermal efficiency is going to suffer...

Both Atkinson or Otto turbo hybrid would have a problem, hybrids have a lot of moments that go directly from engine off to high load, turbo lag and eCVT "rubber" effect... Acceleration feel should be a concern...

Another option would be a Miller cycle, but that requires a supercharger, reducing some efficiency from parasitic losses...

From my point of view, maybe a more powerful battery and electric engine would yield a better result overall...

Maybe for performance-oriented PHEVs, Atkinson cycle engines could be relegated to the sideline.

Let Toyota demonstrate they too can make fast, fun but reliable mid-priced vehicles. And get real fuel savings not the stated EPA when driving the cars harder.

A big reason I can refrain from buying an IS besides money (haha) is the MPG is horrendous lol. Gasoline isn't going to break my piggy bank but still that extra $1-2k/year could be used to buy more options upfront.
 
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Will1991

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@internalaudit , something similar to GR Super Sports right? Loosing a PSD for a more "normal" gearbox and focusing on extreme performance. I'm really looking forward what Toyota is preparing as technical solutions, they tend to think really a lot about their systems.
I really think a IS300h would be the perfect car for you, it drives well, has a nice power, quick enough and not that bad on fuel, it's a bit sad not being offered around there. If you ever get a chance, try one.

@Joaquin Ruhi , the Dynamic Force V8 might be the "i-Force MAX" trademarked some weeks ago.
 

LexsCTJill

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I hope you're right. It would be Toyota's first turbocharged hybrid. Then again, I keep remembering that when the Dynamic Force engines were announced, the graphics hinted at a Dynamic Force V8...

Maybe the Tundra loses the turbo part? And just goes with V6 and hybrid.
 

Levi

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I find a bit intriguing a turbo hybrid from Toyota, running a Atkinson cycle makes for low exhaust pressure which doesn't work very well for turbos... I even don't know if turbo-ing a Atkinson will not decrease efficiency on low-medium engine loads (were the engine spends most of the time)... Unless they return to a Otto cycle, but then the thermal efficiency is going to suffer...

Both Atkinson or Otto turbo hybrid would have a problem, hybrids have a lot of moments that go directly from engine off to high load, turbo lag and eCVT "rubber" effect... Acceleration feel should be a concern...

Another option would be a Miller cycle, but that requires a supercharger, reducing some efficiency from parasitic losses...

From my point of view, maybe a more powerful battery and electric engine would yield a better result overall...

Doesn't every other car maker only do HEVs and PHEVs in combination with turbocharged ICEs, including supercars?
 

Will1991

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Doesn't every other car maker only do HEVs and PHEVs in combination with turbocharged ICEs, including supercars?

Supercars are different, they’re electrified for performance without comprimisse and Toyota is also doing a turbo hybrid supercar, GR Super Sports. Most off them don’t do almost any distance without their ICE working in normal driving conditions, which doesn’t make much sense for a sedan.

As for regular HEV and PHEV’s they aren’t any faster and considerable worse on fuel economy than a equivalent HSD with a clear power deficit when traction battery runs low (which doesn’t happen on HSD) and aren’t as reliable.

Honest question, which turbo HEV? I'm not remembering any at the moment... PHEV's VAG has some, but PHEV are easier because you can program it to don't do so many engine restarts... Once the traction battery requires power, just make the ICE charge it more than it needs, and then we have cars on sale that are worse on fuel economy than a similar power non-PHEV powertrain (2020 330e) when you run without charging the battery at home.
 
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ssun30

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I find a bit intriguing a turbo hybrid from Toyota, running a Atkinson cycle makes for low exhaust pressure which doesn't work very well for turbos... I even don't know if turbo-ing a Atkinson will not decrease efficiency on low-medium engine loads (were the engine spends most of the time)... Unless they return to a Otto cycle, but then the thermal efficiency is going to suffer...
This is incorrect. All modern 'Atkinson cycle' engines use simulated Atkinson cycle by using the VVT mechanism to adjust the intake charge to equilibrate with ambient air. All these engines operate in Otto mode at high load and rpm (e.g. WOT) to increase torque. The Atkinson cycle region is defined on the engine mapping. Hybrid engines (FXS) have wider Atkinson region and higher expansion ratio than the regular version (FKS).

For turbocharging, the engine operates in Otto mode when boost is required and switches back to Atkinson mode when off boost (such as cruising). This effectively gives the engine variable compression ratio without employing a full VCT system. Such mechanism has been used on the 8AR-FTS, L15B and EA211 Evo AFAIK. Atkinson cycle and turbocharging are not mutually-exclusive and the combination is found on millions of vehicles. It does not decrease efficiency but instead increases it: most regular turbocharged engines have peak efficiency between 33-35%, while those with combined cycle could reach 36-38%.

Both Atkinson or Otto turbo hybrid would have a problem, hybrids have a lot of moments that go directly from engine off to high load, turbo lag and eCVT "rubber" effect... Acceleration feel should be a concern...
This is exact opposite of reality. Hybrid system actually masks turbo lag via torque-filling from the motor. The MG1 could also rapidly ramp up engine rpm to get it into boost in a power-split hybrid system similar to doing a 'clutch-kick' in a manual car to rapidly spool up.

Another option would be a Miller cycle, but that requires a supercharger, reducing some efficiency from parasitic losses...
The term 'Miller cycle' is used very loosely in the industry to refer to both turbocharged and supercharged Atkinson cycle engines. The textbook definition is out of date.

So in summary, Atkinson cycle, turbocharging, and hybridization work very well together when power density is required. They just don't compete with a NA hybrid in raw efficiency.
 
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You could move those discussions to the powertrain thread, which I will be making a major update to.

I wonder what happened to this diagram that we were referencing over two years ago? Is this diagram relevant still? Can we make newer and better predictions on the diagram now that we know what's going on a little more at Toyota/Lexus?

3901
 
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ssun30

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I wish I could edit really old posts. I want to change the first three posts since they are now outdated information (and very wordy). The latest update is based on their 2018 report on powertrain development. They should be releasing another report when the next new ICE launches (probably the 2.4T, or V8TT).

The first image is about engines, transmission, and hybrid systems:

3903

The second part is about their new 4WD/AWD systems:

3902

Could admin replace post #2 with this and delete #3?
 

LexsCTJill

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I wish I could edit really old posts. I want to change the first three posts since they are now outdated information (and very wordy). The latest update is based on their 2018 report on powertrain development. They should be releasing another report when the next new ICE launches (probably the 2.4T, or V8TT).

The first image is about engines, transmission, and hybrid systems:

View attachment 3903

The second part is about their new 4WD/AWD systems:

View attachment 3902

Could admin replace post #2 with this and delete #3?

When you crossed out the #5 V8? Is that an assumption or did you just assume there would be a V8?
 

Will1991

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This is incorrect. All modern 'Atkinson cycle' engines use simulated Atkinson cycle by using the VVT mechanism to adjust the intake charge to equilibrate with ambient air. All these engines operate in Otto mode at high load and rpm (e.g. WOT) to increase torque. The Atkinson cycle region is defined on the engine mapping. Hybrid engines (FXS) have wider Atkinson region and higher expansion ratio than the regular version (FKS).

Are you sure about all of them? If my memory is right the only hybrid engine with VVT-iW is the 8GR-FXS (500h moniker).

This is exact opposite of reality. Hybrid system actually masks turbo lag via torque-filling from the motor. The MG1 could also rapidly ramp up engine rpm to get it into boost in a power-split hybrid system similar to doing a 'clutch-kick' in a manual car to rapidly spool up.

Very well remembered, I wasn't thinking about that possibility.