qtb007

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Would adding vvti to the T24A allow it to meet the 2027 emission requirements for BOF applications? Adding vvti to existing engines isn’t anything new for Toyota. They did that to the UZ, JZ, and I believe the FZ engines.

The T24 has both intake and exhaust VVT. It just doesn't have the ultra wide angle VVT. It has the same style solenoid for VVT-iW like the 2GR-FKS, but it really depends if the valves and pistons have clearance at those extreme angles of holding the valves open. Which could be addressed, maybe, with a piston shape change. The VVT-iEW mechanism is pretty drastically different, so it would require substantial changes to the timing chain cover and who knows what else.

Based on the overall direction change of moving to shorter stroke engines, I expect that they considered what it would take to meet the 2027 emissions with the T24, and decided that, as a system, it would make more financial sense to build some flexibility into the upcoming 2.0T.

Toyota's engine manufacturing processes are very flexible already, so it isn't like they toss out all the equipment for the T24 lines. They are already building the A25, M20, and other engines on those same lines.
 

ssun30

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If they want to keep the specific output and improve thermal efficiency at the same time, the engine head could become very complex like the new B58 evolution. They need to combine VVT-iEW and Valvematic and figure out how to package that with D-4S now that the direct injector is moved to the top of the cylinder. That kind of complexity is necessary to remove any last bit of pumping loss (the main reason why BMW engines are so efficient).

The 2.0T doesn't seem to use electric assisted turbo or sequential turbocharging so I'm curious how they will deal with the turbo lag at that high specific output.
 

Flagship1

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Someone unblurred the vehicle in the video...


2024-AMG-C63SE-SEDAN-FMG-004-1UP-DR.jpg

If they want to keep the specific output and improve thermal efficiency at the same time, the engine head could become very complex like the new B58 evolution. They need to combine VVT-iEW and Valvematic and figure out how to package that with D-4S now that the direct injector is moved to the top of the cylinder. That kind of complexity is necessary to remove any last bit of pumping loss (the main reason why BMW engines are so efficient).

The 2.0T doesn't seem to use electric assisted turbo or sequential turbocharging so I'm curious how they will deal with the turbo lag at that high specific output.
Give it some battery, blend and done
 

qtb007

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If they want to keep the specific output and improve thermal efficiency at the same time, the engine head could become very complex like the new B58 evolution. They need to combine VVT-iEW and Valvematic and figure out how to package that with D-4S now that the direct injector is moved to the top of the cylinder. That kind of complexity is necessary to remove any last bit of pumping loss (the main reason why BMW engines are so efficient).

The 2.0T doesn't seem to use electric assisted turbo or sequential turbocharging so I'm curious how they will deal with the turbo lag at that high specific output.

I expect that electric motors will fill in the gap more often than not.

TBH, though, my GRC has very little turbo lag. From my experience, the wastegate is being managed very intently to prevent low speed preignition. If the engine speed is too low and the vehicle load is high, the ECU is keeping the wastegate open/partially open to prevent LSPI until things have reached some equilibrium where the boost will then build. I don't consider this lag... this is the ECU protecting the engine. The ECU also limits boost when the vehicle is not warmed up. If I turn the car on and try to accelerate hard right off the bat, it feels more like 200hp. A lot of words to say that I don't think "turbo lag" on modern cars is so much a limitation of the turbine to spool but a limitation set by the ECU.
 

sl0519

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If they want to keep the specific output and improve thermal efficiency at the same time, the engine head could become very complex like the new B58 evolution. They need to combine VVT-iEW and Valvematic and figure out how to package that with D-4S now that the direct injector is moved to the top of the cylinder. That kind of complexity is necessary to remove any last bit of pumping loss (the main reason why BMW engines are so efficient).

The 2.0T doesn't seem to use electric assisted turbo or sequential turbocharging so I'm curious how they will deal with the turbo lag at that high specific output.

Really don't care how they achieve it. Just want good power and aural experience.
The current 4 cyl is lagging in every department, with rattly as* nvh being the worst offender of all. Even Mazda or Volvo's 4 can put it into shame.
They were very competitive back in the NA era. What have they been doing the past decade?
With EV demand slowing down, now it's the time to bring their motorsport engines to mass production cars!
 

carguy420

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I don't even know about Best Car anymore. This one is about the GR Starlet, at first they say it would be a 3 door hatch but now say it will be a 5 door hatch. Previously they said it would use Daihatsu's platform but now they say it would use the Yaris' GA-B platform.

I just hope this rumour is accurate and isn't just one of Best Car's “best wishes”, because almost all the affordable small hot hatchbacks are gone, like the only one left right now is the current gen Suzuki Swift Sport, but even that car's future is kinda blurry. Yes, Best Car does have a rumour saying that the Swift Sport will have new generation debuting at the end of this year, but usually their rumours about car brands that aren't Toyota tend to be less accurate.
 

ssun30

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I don't even know about Best Car anymore. This one is about the GR Starlet, at first they say it would be a 3 door hatch but now say it will be a 5 door hatch. Previously they said it would use Daihatsu's platform but now they say it would use the Yaris' GA-B platform.
Most badge engineered Toyota products based on Daihatsu have been cancelled after the scandal. It's likely the flaws with DNGA are fundamental and whatever bandaid solution they use for current products to pass crash tests is very expensive.

Making the GR Starlet a 5 door makes sense since they don't need to engineer a separate 3 door chassis just for the GR.
 

carguy420

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Most badge engineered Toyota products based on Daihatsu have been cancelled after the scandal. It's likely the flaws with DNGA are fundamental and whatever bandaid solution they use for current products to pass crash tests is very expensive.

Making the GR Starlet a 5 door makes sense since they don't need to engineer a separate 3 door chassis just for the GR.
The DNGA cars kinda suck at absorbing the impact from crashes (see the frontal offset crash test of the Toyota Raize performed by Latin NCAP) and I doubt this platform without any sort of thorough modifications is good enough for them to develop a hot hatchback that's both lightweight, safe and has good chassis rigidity.
 

Flagship1

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Toyota is electrifying their tnga lineup is a very special way, next gen models become hev or phev. Will lexus follow a more aggressive pace, and electrify current generation models like the very popular RX and NX and drop their slow less pricey gas trims?

Right now, the gas only RX is getting a very generous $4k factory to customer lease incentive, while the hev have none. Phevs seem to also have some funds that are being passed onto the customer surprisingly.
 
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r/cars also did the same as well.

But reading this article, why do journalists not understand that transmissions meant for transverse applications are NOT the same as transmissions needed for longitudinal vehicles?

As the YouTube channel Toyota Times revealed in a video, at a press event in Japan a few months ago, journalists had the chance to ride in a new 400-hp Lexus IS prototype with a 2.0-liter turbocharged four-cylinder engine and an eight-speed automatic transmission—possibly similar to the automatic seen in the GR Corolla and GR Yaris. A Toyota Hilux with a six-speed manual and 2.0-liter turbo rated at a claimed 300 horsepower was also undergoing testing at the event.
*sigh*