Official Lexus Future Product & Powertrain Megathread

[qtb007]

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]

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]

Someone unblurred the vehicle in the video...

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]

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]

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!

 

[Kelvin2020]

Toyota reportedly building battery plant for Lexus

Toyota might build a Japanese battery plant as part of its central EV supply chain hub.

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