Lexus August 2018 Sales Report

Gecko

This discussion started with Mike saying neither the 8AR-FTS nor V35A-FTS have really impressed him and how both feel "adequate." Then followed it up by saying there was a time when Lexus engines were truly impressive.

I agreed with this and stated that Lexus is playing catch up with respect to turbocharging. Lexus touts V35A-FTS as a V8 replacement but you and I agree that it is not. So the point here is: Is V35A-FTS competitive with other turbo V6s? Yes, for sure. Is it a replacement for a V8? No. So based on Lexus' own claims of V35A-FTS being competitive with Mercedes' and BMW's turbo V8s, this engine is not particularly impressive.

The thing is, the V6TT can in theory be a V8 alternative, when the V8 is NA. But it should not be compared to the V8TT that is used in Merc and Audi. The only replacement for a big NA V8 is a smaller Twin Turbo V8. Which is what Mercedes has done.
The LS had a relatively small NA V8, so a TT v6 is an acceptable alternative.

Gecko

This discussion started with Mike saying neither the 8AR-FTS nor V35A-FTS have really impressed him and how both feel "adequate." Then followed it up by saying there was a time when Lexus engines were truly impressive.

I agreed with this and stated that Lexus is playing catch up with respect to turbocharging. Lexus touts V35A-FTS as a V8 replacement but you and I agree that it is not. So the point here is: Is V35A-FTS competitive with other turbo V6s? Yes, for sure. Is it a replacement for a V8? No. So based on Lexus' own claims of V35A-FTS being competitive with Mercedes' and BMW's turbo V8s, this engine is not particularly impressive.

The thing is, the V6TT can in theory be a V8 alternative, when the V8 is NA. But it should not be compared to the V8TT that is used in Merc and Audi. The only replacement for a big NA V8 is a smaller Twin Turbo V8. Which is what Mercedes has done.
The LS had a relatively small NA V8, so a TT v6 is an acceptable alternative.

ssun30

Has anyone here wondered where the future holds for Valvematic? IMO it's the most sophisticated valvetrain technology TMC has been developing. And I was surprised it was not part of the Dynamic Force package at launch. The 3ZR-FAE got the same 36% efficiency and 160hp as the 6AR-FSE, despite the latter having the luxury of D-4S and Miller Cycle operation.

Continuous VVL is a very strong tool to improve performance and efficiency, most importantly it allows NA engines to be very competitive against forced induction engines. Surely there's the extra cost, but it should still be cheaper than a turbo system.

It would be interesting to see the GR and UR getting a final tech upgrade with Valvematic. 100hp/L is definitely within reach since the two have a lot of revving potential, not to mention extra efficiency and improved torque curve. A 350hp 2GR and 500hp 2UR 'final edition' could be the last hurrah for natural aspiration. And the best part is that it can be done today. But alas Toyota is known for not bothering the effort no matter how trivial the effort is.

I once read that the 2AR could have had Valvematic mechanisms added with basically no modification of the head because it had an extra cam cradle not normally found in DOHC heads. Upon further research, the 2GR has a similar setup.

2AR-FE:



2ZR-FAE:

2GR-FE:



In the -FAE head, the Valvematic mechanism rides lower in the camshaft housing, with the camshafts sitting higher than normal. As I've read, it would take basically a new cam housing, camshafts, and electronic controls to add this tech to these older engines without the need for a new head casting. However, TMC never did this with the 2AR, opting instead to wait it out and release the new A25A. I'm not sure if the UR series have this cam housing, but they might.

Edit: As for Valvematic + D4-S, it might be an issue of packaging as well as cost. With all this stuff stacked on the head, it may be difficult to make everything fit.

ssun30

Has anyone here wondered where the future holds for Valvematic? IMO it's the most sophisticated valvetrain technology TMC has been developing. And I was surprised it was not part of the Dynamic Force package at launch. The 3ZR-FAE got the same 36% efficiency and 160hp as the 6AR-FSE, despite the latter having the luxury of D-4S and Miller Cycle operation.

Continuous VVL is a very strong tool to improve performance and efficiency, most importantly it allows NA engines to be very competitive against forced induction engines. Surely there's the extra cost, but it should still be cheaper than a turbo system.

It would be interesting to see the GR and UR getting a final tech upgrade with Valvematic. 100hp/L is definitely within reach since the two have a lot of revving potential, not to mention extra efficiency and improved torque curve. A 350hp 2GR and 500hp 2UR 'final edition' could be the last hurrah for natural aspiration. And the best part is that it can be done today. But alas Toyota is known for not bothering the effort no matter how trivial the effort is.

I once read that the 2AR could have had Valvematic mechanisms added with basically no modification of the head because it had an extra cam cradle not normally found in DOHC heads. Upon further research, the 2GR has a similar setup.

2AR-FE:



2ZR-FAE:

2GR-FE:



In the -FAE head, the Valvematic mechanism rides lower in the camshaft housing, with the camshafts sitting higher than normal. As I've read, it would take basically a new cam housing, camshafts, and electronic controls to add this tech to these older engines without the need for a new head casting. However, TMC never did this with the 2AR, opting instead to wait it out and release the new A25A. I'm not sure if the UR series have this cam housing, but they might.

Edit: As for Valvematic + D4-S, it might be an issue of packaging as well as cost. With all this stuff stacked on the head, it may be difficult to make everything fit.

ssun30

Has anyone here wondered where the future holds for Valvematic? IMO it's the most sophisticated valvetrain technology TMC has been developing. And I was surprised it was not part of the Dynamic Force package at launch. The 3ZR-FAE got the same 36% efficiency and 160hp as the 6AR-FSE, despite the latter having the luxury of D-4S and Miller Cycle operation.

Continuous VVL is a very strong tool to improve performance and efficiency, most importantly it allows NA engines to be very competitive against forced induction engines. Surely there's the extra cost, but it should still be cheaper than a turbo system.

It would be interesting to see the GR and UR getting a final tech upgrade with Valvematic. 100hp/L is definitely within reach since the two have a lot of revving potential, not to mention extra efficiency and improved torque curve. A 350hp 2GR and 500hp 2UR 'final edition' could be the last hurrah for natural aspiration. And the best part is that it can be done today. But alas Toyota is known for not bothering the effort no matter how trivial the effort is.

I once read that the 2AR could have had Valvematic mechanisms added with basically no modification of the head because it had an extra cam cradle not normally found in DOHC heads. Upon further research, the 2GR has a similar setup.

2AR-FE:



2ZR-FAE:

2GR-FE:



In the -FAE head, the Valvematic mechanism rides lower in the camshaft housing, with the camshafts sitting higher than normal. As I've read, it would take basically a new cam housing, camshafts, and electronic controls to add this tech to these older engines without the need for a new head casting. However, TMC never did this with the 2AR, opting instead to wait it out and release the new A25A. I'm not sure if the UR series have this cam housing, but they might.

Edit: As for Valvematic + D4-S, it might be an issue of packaging as well as cost. With all this stuff stacked on the head, it may be difficult to make everything fit.

TheNerdyPotato

I once read that the 2AR could have had Valvematic mechanisms added with basically no modification of the head because it had an extra cam cradle not normally found in DOHC heads. Upon further research, the 2GR has a similar setup.

2AR-FE:



2ZR-FAE:

2GR-FE:



In the -FAE head, the Valvematic mechanism rides lower in the camshaft housing, with the camshafts sitting higher than normal. As I've read, it would take basically a new cam housing, camshafts, and electronic controls to add this tech to these older engines without the need for a new head casting. However, TMC never did this with the 2AR, opting instead to wait it out and release the new A25A. I'm not sure if the UR series have this cam housing, but they might.

Edit: As for Valvematic + D4-S, it might be an issue of packaging as well as cost. With all this stuff stacked on the head, it may be difficult to make everything fit.

Valvematic engines produce around 10% more power than their non-Valvematic counterparts, Toyota really should implement it with their Dynamic Force engines.

Theoretically an M20A with Valvematic can produce 185hp, quite a decent increase.

But how's the torque curve of the naturally aspirated Dynamic Force engines? Because it's peak torque comes in at quite a high rpm.

TheNerdyPotato

I once read that the 2AR could have had Valvematic mechanisms added with basically no modification of the head because it had an extra cam cradle not normally found in DOHC heads. Upon further research, the 2GR has a similar setup.

2AR-FE:



2ZR-FAE:

2GR-FE:



In the -FAE head, the Valvematic mechanism rides lower in the camshaft housing, with the camshafts sitting higher than normal. As I've read, it would take basically a new cam housing, camshafts, and electronic controls to add this tech to these older engines without the need for a new head casting. However, TMC never did this with the 2AR, opting instead to wait it out and release the new A25A. I'm not sure if the UR series have this cam housing, but they might.

Edit: As for Valvematic + D4-S, it might be an issue of packaging as well as cost. With all this stuff stacked on the head, it may be difficult to make everything fit.

Valvematic engines produce around 10% more power than their non-Valvematic counterparts, Toyota really should implement it with their Dynamic Force engines.

Theoretically an M20A with Valvematic can produce 185hp, quite a decent increase.

But how's the torque curve of the naturally aspirated Dynamic Force engines? Because it's peak torque comes in at quite a high rpm.

TheNerdyPotato

I once read that the 2AR could have had Valvematic mechanisms added with basically no modification of the head because it had an extra cam cradle not normally found in DOHC heads. Upon further research, the 2GR has a similar setup.

2AR-FE:



2ZR-FAE:

2GR-FE:



In the -FAE head, the Valvematic mechanism rides lower in the camshaft housing, with the camshafts sitting higher than normal. As I've read, it would take basically a new cam housing, camshafts, and electronic controls to add this tech to these older engines without the need for a new head casting. However, TMC never did this with the 2AR, opting instead to wait it out and release the new A25A. I'm not sure if the UR series have this cam housing, but they might.

Edit: As for Valvematic + D4-S, it might be an issue of packaging as well as cost. With all this stuff stacked on the head, it may be difficult to make everything fit.

Valvematic engines produce around 10% more power than their non-Valvematic counterparts, Toyota really should implement it with their Dynamic Force engines.

Theoretically an M20A with Valvematic can produce 185hp, quite a decent increase.

But how's the torque curve of the naturally aspirated Dynamic Force engines? Because it's peak torque comes in at quite a high rpm.

carguy420

Valvematic engines produce around 10% more power than their non-Valvematic counterparts, Toyota really should implement it with their Dynamic Force engines.

Theoretically an M20A with Valvematic can produce 185hp, quite a decent increase.

But how's the torque curve of the naturally aspirated Dynamic Force engines? Because it's peak torque comes in at quite a high rpm.

The only Valvematic engine released in the US is the 2ZR-FAE found only in the Corolla Eco. It increased power over the standard -FE from 132hp to 140hp, or a 6% increase. Still, 178hp (168hp +6%) out of a 2.0l economy car motor would be very respectable.

One thing I'd like to see from TMC is hybrid motors that can do part-time Otto cycle, which would allow the Prius, et al, to have some significant getup and go when needed, even if only under WOT.

carguy420

Valvematic engines produce around 10% more power than their non-Valvematic counterparts, Toyota really should implement it with their Dynamic Force engines.

Theoretically an M20A with Valvematic can produce 185hp, quite a decent increase.

But how's the torque curve of the naturally aspirated Dynamic Force engines? Because it's peak torque comes in at quite a high rpm.

The only Valvematic engine released in the US is the 2ZR-FAE found only in the Corolla Eco. It increased power over the standard -FE from 132hp to 140hp, or a 6% increase. Still, 178hp (168hp +6%) out of a 2.0l economy car motor would be very respectable.

One thing I'd like to see from TMC is hybrid motors that can do part-time Otto cycle, which would allow the Prius, et al, to have some significant getup and go when needed, even if only under WOT.

carguy420

Valvematic engines produce around 10% more power than their non-Valvematic counterparts, Toyota really should implement it with their Dynamic Force engines.

Theoretically an M20A with Valvematic can produce 185hp, quite a decent increase.

But how's the torque curve of the naturally aspirated Dynamic Force engines? Because it's peak torque comes in at quite a high rpm.

The only Valvematic engine released in the US is the 2ZR-FAE found only in the Corolla Eco. It increased power over the standard -FE from 132hp to 140hp, or a 6% increase. Still, 178hp (168hp +6%) out of a 2.0l economy car motor would be very respectable.

One thing I'd like to see from TMC is hybrid motors that can do part-time Otto cycle, which would allow the Prius, et al, to have some significant getup and go when needed, even if only under WOT.

This illustration is for the 2UR-GSE for a 2014 ISF. You can clearly see the camshaft housing listed as item 4 in the upper-right portion of the image. I have found similar parts while looking up IPCs for the 1UR-FE and 3UR-FE. This would imply that the UR series is Valvematic-capable with minimal modification.

This illustration is for the 2UR-GSE for a 2014 ISF. You can clearly see the camshaft housing listed as item 4 in the upper-right portion of the image. I have found similar parts while looking up IPCs for the 1UR-FE and 3UR-FE. This would imply that the UR series is Valvematic-capable with minimal modification.

This illustration is for the 2UR-GSE for a 2014 ISF. You can clearly see the camshaft housing listed as item 4 in the upper-right portion of the image. I have found similar parts while looking up IPCs for the 1UR-FE and 3UR-FE. This would imply that the UR series is Valvematic-capable with minimal modification.

TheNerdyPotato

One thing I'd like to see from TMC is hybrid motors that can do part-time Otto cycle, which would allow the Prius, et al, to have some significant getup and go when needed, even if only under WOT.

That would be VERY interesting.

Toyota/Lexus pioneered dual Otto/Atkinson cycle functionality on version 2 of the 2UR-FSE 5-liter V8 and on a number of "FKS" engines (all non-hybrid). This at least partially inspired the later 2015 evolution of VW/Audi's EA888 2-liter 4-cylinder turbo and Hyundai's Nu MPi Atkinson Cycle 2-liter 4-cylinder engines.

Turning that on its head to add Otto cycle functionality to Toyota/Lexus hybrids to increase performance sounds like a great idea. Yet, I vaguely recall a Lexus insider once telling me that those hybrids actually already achieve part-time Otto cycle functionality, and Wikipedia's Atkinson Cycle article implies that being the case with most if not all so-called modern Atkinson Cycle engines.

TheNerdyPotato

One thing I'd like to see from TMC is hybrid motors that can do part-time Otto cycle, which would allow the Prius, et al, to have some significant getup and go when needed, even if only under WOT.

That would be VERY interesting.

Toyota/Lexus pioneered dual Otto/Atkinson cycle functionality on version 2 of the 2UR-FSE 5-liter V8 and on a number of "FKS" engines (all non-hybrid). This at least partially inspired the later 2015 evolution of VW/Audi's EA888 2-liter 4-cylinder turbo and Hyundai's Nu MPi Atkinson Cycle 2-liter 4-cylinder engines.

Turning that on its head to add Otto cycle functionality to Toyota/Lexus hybrids to increase performance sounds like a great idea. Yet, I vaguely recall a Lexus insider once telling me that those hybrids actually already achieve part-time Otto cycle functionality, and Wikipedia's Atkinson Cycle article implies that being the case with most if not all so-called modern Atkinson Cycle engines.

TheNerdyPotato

One thing I'd like to see from TMC is hybrid motors that can do part-time Otto cycle, which would allow the Prius, et al, to have some significant getup and go when needed, even if only under WOT.

That would be VERY interesting.

Toyota/Lexus pioneered dual Otto/Atkinson cycle functionality on version 2 of the 2UR-FSE 5-liter V8 and on a number of "FKS" engines (all non-hybrid). This at least partially inspired the later 2015 evolution of VW/Audi's EA888 2-liter 4-cylinder turbo and Hyundai's Nu MPi Atkinson Cycle 2-liter 4-cylinder engines.

Turning that on its head to add Otto cycle functionality to Toyota/Lexus hybrids to increase performance sounds like a great idea. Yet, I vaguely recall a Lexus insider once telling me that those hybrids actually already achieve part-time Otto cycle functionality, and Wikipedia's Atkinson Cycle article implies that being the case with most if not all so-called modern Atkinson Cycle engines.

carguy420

Valvematic engines produce around 10% more power than their non-Valvematic counterparts, Toyota really should implement it with their Dynamic Force engines.

Theoretically an M20A with Valvematic can produce 185hp, quite a decent increase.

But how's the torque curve of the naturally aspirated Dynamic Force engines? Because it's peak torque comes in at quite a high rpm.

Dynamic Force engines have weak low-end torque because they operate in Atkinson Cycle at low rpm.

Continuous VVL could smooth out the torque curve. Allowing strong low-end torque and an aggressive high rpm cam profile to coexist. A well implemented CVVL could make a flat torque curve on a NA engine like turbocharged engines. This is why Valvematic could be a very nice addition to Dynamic Force.

carguy420

Valvematic engines produce around 10% more power than their non-Valvematic counterparts, Toyota really should implement it with their Dynamic Force engines.

Theoretically an M20A with Valvematic can produce 185hp, quite a decent increase.

But how's the torque curve of the naturally aspirated Dynamic Force engines? Because it's peak torque comes in at quite a high rpm.

Dynamic Force engines have weak low-end torque because they operate in Atkinson Cycle at low rpm.

Continuous VVL could smooth out the torque curve. Allowing strong low-end torque and an aggressive high rpm cam profile to coexist. A well implemented CVVL could make a flat torque curve on a NA engine like turbocharged engines. This is why Valvematic could be a very nice addition to Dynamic Force.

carguy420

Valvematic engines produce around 10% more power than their non-Valvematic counterparts, Toyota really should implement it with their Dynamic Force engines.

Theoretically an M20A with Valvematic can produce 185hp, quite a decent increase.

But how's the torque curve of the naturally aspirated Dynamic Force engines? Because it's peak torque comes in at quite a high rpm.

Dynamic Force engines have weak low-end torque because they operate in Atkinson Cycle at low rpm.

Continuous VVL could smooth out the torque curve. Allowing strong low-end torque and an aggressive high rpm cam profile to coexist. A well implemented CVVL could make a flat torque curve on a NA engine like turbocharged engines. This is why Valvematic could be a very nice addition to Dynamic Force.

Joaquin Ruhi

That would be VERY interesting.

Toyota/Lexus pioneered dual Otto/Atkinson cycle functionality on version 2 of the 2UR-FSE 5-liter V8 and on a number of "FKS" engines (all non-hybrid). This at least partially inspired the later 2015 evolution of VW/Audi's EA888 2-liter 4-cylinder turbo and Hyundai's Nu MPi Atkinson Cycle 2-liter 4-cylinder engines.

Turning that on its head to add Otto cycle functionality to Toyota/Lexus hybrids to increase performance sounds like a great idea. Yet, I vaguely recall a Lexus insider once telling me that those hybrids actually already achieve part-time Otto cycle functionality, and Wikipedia's Atkinson Cycle article implies that being the case with most if not all so-called modern Atkinson Cycle engines.

All modern 'Atkinson Cycle' engines run Otto Mode in transient (non-steady-state) workload. Otherwise throttle response would be so poor the engine becomes unusable. The engine also runs Otto Mode at start-up to heat up the catalytic converter faster and reduce NOx. This is confirmed by a drivetrain calibration engineer at Toyota.

According to this guy the 'Otto-Atkinson Dual Cycle' is just a marketing term. They didn't want people to relate their flagship performance engine to the weak eco engine on the Prius. The principle is no different from regular hybrid engines. The implementation is of course a little different. The so-called 'Dual-Cycle' engines have a wider operating window for Otto Cycle while the 'Eco-Oriented' hybrid engines have a wider operating window for Atkinson Cycle.

And BTW, since this 'Dual-Cycle' thing is just a play with cam profile and fuel map. Nothing prevents them from combining dual-cycle operation and Valvematic. But, as some pointed out above, it would be a packaging challenge.

Joaquin Ruhi

That would be VERY interesting.

Toyota/Lexus pioneered dual Otto/Atkinson cycle functionality on version 2 of the 2UR-FSE 5-liter V8 and on a number of "FKS" engines (all non-hybrid). This at least partially inspired the later 2015 evolution of VW/Audi's EA888 2-liter 4-cylinder turbo and Hyundai's Nu MPi Atkinson Cycle 2-liter 4-cylinder engines.

Turning that on its head to add Otto cycle functionality to Toyota/Lexus hybrids to increase performance sounds like a great idea. Yet, I vaguely recall a Lexus insider once telling me that those hybrids actually already achieve part-time Otto cycle functionality, and Wikipedia's Atkinson Cycle article implies that being the case with most if not all so-called modern Atkinson Cycle engines.

All modern 'Atkinson Cycle' engines run Otto Mode in transient (non-steady-state) workload. Otherwise throttle response would be so poor the engine becomes unusable. The engine also runs Otto Mode at start-up to heat up the catalytic converter faster and reduce NOx. This is confirmed by a drivetrain calibration engineer at Toyota.

According to this guy the 'Otto-Atkinson Dual Cycle' is just a marketing term. They didn't want people to relate their flagship performance engine to the weak eco engine on the Prius. The principle is no different from regular hybrid engines. The implementation is of course a little different. The so-called 'Dual-Cycle' engines have a wider operating window for Otto Cycle while the 'Eco-Oriented' hybrid engines have a wider operating window for Atkinson Cycle.

And BTW, since this 'Dual-Cycle' thing is just a play with cam profile and fuel map. Nothing prevents them from combining dual-cycle operation and Valvematic. But, as some pointed out above, it would be a packaging challenge.

Joaquin Ruhi

That would be VERY interesting.

Toyota/Lexus pioneered dual Otto/Atkinson cycle functionality on version 2 of the 2UR-FSE 5-liter V8 and on a number of "FKS" engines (all non-hybrid). This at least partially inspired the later 2015 evolution of VW/Audi's EA888 2-liter 4-cylinder turbo and Hyundai's Nu MPi Atkinson Cycle 2-liter 4-cylinder engines.

Turning that on its head to add Otto cycle functionality to Toyota/Lexus hybrids to increase performance sounds like a great idea. Yet, I vaguely recall a Lexus insider once telling me that those hybrids actually already achieve part-time Otto cycle functionality, and Wikipedia's Atkinson Cycle article implies that being the case with most if not all so-called modern Atkinson Cycle engines.

All modern 'Atkinson Cycle' engines run Otto Mode in transient (non-steady-state) workload. Otherwise throttle response would be so poor the engine becomes unusable. The engine also runs Otto Mode at start-up to heat up the catalytic converter faster and reduce NOx. This is confirmed by a drivetrain calibration engineer at Toyota.

According to this guy the 'Otto-Atkinson Dual Cycle' is just a marketing term. They didn't want people to relate their flagship performance engine to the weak eco engine on the Prius. The principle is no different from regular hybrid engines. The implementation is of course a little different. The so-called 'Dual-Cycle' engines have a wider operating window for Otto Cycle while the 'Eco-Oriented' hybrid engines have a wider operating window for Atkinson Cycle.

And BTW, since this 'Dual-Cycle' thing is just a play with cam profile and fuel map. Nothing prevents them from combining dual-cycle operation and Valvematic. But, as some pointed out above, it would be a packaging challenge.

TheNerdyPotato

The only Valvematic engine released in the US is the 2ZR-FAE found only in the Corolla Eco. It increased power over the standard -FE from 132hp to 140hp, or a 6% increase. Still, 178hp (168hp +6%) out of a 2.0l economy car motor would be very respectable.

One thing I'd like to see from TMC is hybrid motors that can do part-time Otto cycle, which would allow the Prius, et al, to have some significant getup and go when needed, even if only under WOT.

hm, i dont think it would increase power in modern engine with vvt-iw and D4S though. Not only that, it also increased it only at top end and it was not felt in normal driving, unlike D4S. You can just check Corolla Eco vs regular one.

TheNerdyPotato

The only Valvematic engine released in the US is the 2ZR-FAE found only in the Corolla Eco. It increased power over the standard -FE from 132hp to 140hp, or a 6% increase. Still, 178hp (168hp +6%) out of a 2.0l economy car motor would be very respectable.

One thing I'd like to see from TMC is hybrid motors that can do part-time Otto cycle, which would allow the Prius, et al, to have some significant getup and go when needed, even if only under WOT.

hm, i dont think it would increase power in modern engine with vvt-iw and D4S though. Not only that, it also increased it only at top end and it was not felt in normal driving, unlike D4S. You can just check Corolla Eco vs regular one.

TheNerdyPotato

The only Valvematic engine released in the US is the 2ZR-FAE found only in the Corolla Eco. It increased power over the standard -FE from 132hp to 140hp, or a 6% increase. Still, 178hp (168hp +6%) out of a 2.0l economy car motor would be very respectable.

One thing I'd like to see from TMC is hybrid motors that can do part-time Otto cycle, which would allow the Prius, et al, to have some significant getup and go when needed, even if only under WOT.

hm, i dont think it would increase power in modern engine with vvt-iw and D4S though. Not only that, it also increased it only at top end and it was not felt in normal driving, unlike D4S. You can just check Corolla Eco vs regular one.

spwolf

hm, i dont think it would increase power in modern engine with vvt-iw and D4S though. Not only that, it also increased it only at top end and it was not felt in normal driving, unlike D4S. You can just check Corolla Eco vs regular one.

And, I would like to add a striking fact that many people get wrong: Atkinson Cycle does not reduce available torque in regular driving, it increases it. This is because the engine is more efficient, thus more energy is converted to usable work i.e. engine torque for the same amount of fuel injected. Atkinson Cycle is only weaker at WOT, when reduced volumetric efficiency meant less fuel could be burnt. But WOT is not a 'regular driving' scenario anyway.

spwolf

hm, i dont think it would increase power in modern engine with vvt-iw and D4S though. Not only that, it also increased it only at top end and it was not felt in normal driving, unlike D4S. You can just check Corolla Eco vs regular one.

And, I would like to add a striking fact that many people get wrong: Atkinson Cycle does not reduce available torque in regular driving, it increases it. This is because the engine is more efficient, thus more energy is converted to usable work i.e. engine torque for the same amount of fuel injected. Atkinson Cycle is only weaker at WOT, when reduced volumetric efficiency meant less fuel could be burnt. But WOT is not a 'regular driving' scenario anyway.

spwolf

hm, i dont think it would increase power in modern engine with vvt-iw and D4S though. Not only that, it also increased it only at top end and it was not felt in normal driving, unlike D4S. You can just check Corolla Eco vs regular one.

And, I would like to add a striking fact that many people get wrong: Atkinson Cycle does not reduce available torque in regular driving, it increases it. This is because the engine is more efficient, thus more energy is converted to usable work i.e. engine torque for the same amount of fuel injected. Atkinson Cycle is only weaker at WOT, when reduced volumetric efficiency meant less fuel could be burnt. But WOT is not a 'regular driving' scenario anyway.

spwolf

hm, i dont think it would increase power in modern engine with vvt-iw and D4S though. Not only that, it also increased it only at top end and it was not felt in normal driving, unlike D4S. You can just check Corolla Eco vs regular one.

It would change the valve lift and duration while VVT changes the timing. I don't see how those couldn't work together. As for it being for top-end power only, that's OK because ssun30 suggested high-output versions of the 2GR and 2UR. I understand that it doesn't work too well with low-end, as the 2ZR -FE and -FAE have basically the same peak torque rating.

ssun30

And, I would like to add a striking fact that many people get wrong: Atkinson Cycle does not reduce available torque in regular driving, it increases it. This is because the engine is more efficient, thus more energy is converted to usable work i.e. engine torque for the same amount of fuel injected. Atkinson Cycle is only weaker at WOT, when reduced volumetric efficiency meant less fuel could be burnt. But WOT is not a 'regular driving' scenario anyway.

As I understand, the Atkinson cycle reduces the size of the charge in the cylinder, thus reducing power but makes up for it in efficiency. So, it seems like you could say it makes the same amount of torque by burning less fuel? Eh, maybe I'm being semantic...