internalaudit

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Why doesn't Toyota use superchargers, at least on its hybrids?


An electric supercharger performs the same function as an exhaust-driven turbo or an engine-driven supercharger, cramming high-pressure air into the engine's intake to maximize power output. But unlike a conventional turbo or supercharger, an electric blower responds instantaneously, eliminating the delay required to build up RPMs or exhaust flow.

So why can't you just slap an electric blower on your conventional car? It turns out, incorporating an e-supercharger requires extremely complex engine management. And building up no-lag boost with an e-blower requires plenty of electric power—far more than your conventional car's 12-volt system can provide.
 

Sebass

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This is very random, but does anyone have any idea if for future F cars e.g - LC F, (holy crap, that is the only confirmed future F car. 😭), if Lexus will develop a dual-clutch transmission? Or will they just tune the 10-speed torque converter automatic to ben even quicker on the shifts and more aggressive in all possible areas?
 
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This is very random, but does anyone have any idea if for future F cars e.g - LC F, (holy crap, that is the only confirmed future F car. 😭), if Lexus will develop a dual-clutch transmission? Or will they just tune the 10-speed torque converter automatic to ben even quicker on the shifts and more aggressive in all possible areas?

It will use the 10-speed automatic transmission and crank the sh*t out of it to 11 (not 11 gears but like as in 11/10).
 

Joaquin Ruhi

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This is very random, but does anyone have any idea if for future F cars e.g - LC F, (holy crap, that is the only confirmed future F car. 😭), if Lexus will develop a dual-clutch transmission? Or will they just tune the 10-speed torque converter automatic to ben even quicker on the shifts and more aggressive in all possible areas?
For whatever their reasons, Toyota and Lexus have never been partial to dual-clutch transmissions. The closest they've come is the 5-speed SMT (Sequential Manual Transmission) option in the final, 3rd-gen Toyota MR2 and the 6-speed Aisin SA6 single-clutch automated manual in the Lexus LFA, but neither is a dual-clutch transmission.

In the case of the latter, the first part of my Lexus LFA review from 2009 contains this passage:

Those of you surprised by the LFA's relatively simple port-only fuel injection will be further shocked to hear that Lexus engineers chose to forego a dual-clutch arrangement such as that favored by Audi, Porsche and the Nissan GT-R in favor of a single clutch. A paragraph from the initial Lexus USA Newsroom Press Release succinctly offers the company's rationale: "The incredibly quick-revving nature of the LFA’s V10 engine demanded a single ultra-light and responsive clutch, a move that effectively ruled out a double-clutch transmission. The engineers also felt the ASG transmission’s positive and direct shift quality – as opposed to the almost artificial smoothness of current double-clutch transmissions – significantly enhanced the driving experience, making the driver aware of machined parts working together in harmony when changing gears for a satisfying sense of mechanical engagement".
 

Sebass

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I had a feeling, thank you for confirming it. I really do hope that they make the gears shorter, for a 10 speed they are too long right now. If I am correct, the only gears you need to use in the LC 500 from 0 mph up to its top speed, are gears 1 - 6. Gears 7 -10 are highway gears for better mpg, and I can't put it into words how important it is that on future F cars they make gears 1 - 7 shorter and make 7 a non-highway mpg gear. (Essentially have the transmission tuned so gears 1 - 7 are the gears you will need to rip the car from 0 to whatever its top speed will be). In fact, they may even need to make 8th gear a non-highway mpg gear.
 

Sebass

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For whatever their reasons, Toyota and Lexus have never been partial to dual-clutch transmissions. The closest they've come is the 5-speed SMT (Sequential Manual Transmission) option in the final, 3rd-gen Toyota MR2 and the 6-speed Aisin SA6 single-clutch automated manual in the Lexus LFA, but neither is a dual-clutch transmission.

In the case of the latter, the first part of my Lexus LFA review from 2009 contains this passage:
Thanks, the explanation of why the LFA has a single clutch makes sense, but I have heard a lot of people who have driven it say that the shifts feel to slow.
And... wait, wait, wait... You reviewed an LFA? did you drive one? If so, I am both highly jealous but also curious to know if you found the transmission slow.
 

ssun30

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DCT used to be popular since they have similar efficiency to manuals and fast shift speed, but modern ATs have shortened that gap considerably. Also torque converters have the added benefit of massive torque capacity, a desirable property for big turbocharged engines like the V8TT (likely to make over 900N.m). It makes no sense to develop a one-off DCT for like 50ms faster shifts.

I think LFA engineers once said they intentionally limited shift speed on the 6SMT so the driver can clearly feel the mechanical shift.

I had a feeling, thank you for confirming it. I really do hope that they make the gears shorter, for a 10 speed they are too long right now. If I am correct, the only gears you need to use in the LC 500 from 0 mph up to its top speed, are gears 1 - 6. Gears 7 -10 are highway gears for better mpg, and I can't put it into words how important it is that on future F cars they make gears 1 - 7 shorter and make 7 a non-highway mpg gear. (Essentially have the transmission tuned so gears 1 - 7 are the gears you will need to rip the car from 0 to whatever its top speed will be). In fact, they may even need to make 8th gear a non-highway mpg gear.
Four overdrives are not an overkill for a luxury cruiser like the LC. Those super long ODs are there to keep the engine at as low rpm as possible to cruise silently on the Autobahn at over 160km/h.

9 gears are enough to cover a 8.5:1 ratio spread (optimal for luxury cars), 8 is one gear too few, 10 provides that extra quietness at similar complexity to 9.

I don't see what you mean by 'non-highway mpg gear'. Modern AT ratios are not like the old 4/5ATs where there's a clear ratio gap between the drive gears and OD. The 10AT has very close 6-8 so there's no need to shorten the ratios. For the 2UR-GSE it helps to have closer ratios for gear 1-7, but the V8TT will have a very power band compared to the 2UR. What I'm saying is the 10AT is already a quite close ratio gearbox for a turbocharged engine.
 
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Joaquin Ruhi

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Thanks, the explanation of why the LFA has a single clutch makes sense, but I have heard a lot of people who have driven it say that the shifts feel to slow.
And... wait, wait, wait... You reviewed an LFA? did you drive one? If so, I am both highly jealous but also curious to know if you found the transmission slow.
That link I posted earlier was for Part 1 of my review (technical presentation and styling impressions). Yes, I was privileged to drive the LFA for 9 laps of the Homestead-Miami Speedway, an unforgettable experience. Those impressions are in Part 2 of my article.

My transmission impressions from there:

"The transaxle responded quickly and smoothly to both upshifts and downshifts from the paddles, and both the time-to-upshift beeps and rev matching "whompf" from the IS F are present and accounted for in the LFA, but they are muted by the glorious engine and exhaust sounds...

As I got underway, I noticed that the shifts in the black LFA felt far sharper and rougher than they did in the White Avenging Angel. Car-to-car variation? Possibly, but a far more likely explanation is that gearshift speeds can be adjusted in seven stages – from approximately 0.2 seconds for intense track work to 1.0 second for smooth cruising – using the Shift Speed Selection dial, and I'd venture a guess that Scott Pruett prefers the faster response time even at the cost of smoothness versus Hirose Nasure's slower but smoother shift setup. Perhaps it was my response to the transaxle shift setting, or perhaps the overconfidence that such an amazingly capable car inspires, but traces of sloppiness seeped into my driving, yet the LFA just motioned itself into the ideal line after the briefest rear twitch."

A link to my full driving impressions:
https://www.lexusfforum.com/forums/showthread.php?t=2065
 

Will1991

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Isn't a bit hard to say "fall in America" when it's only around 10% less than the all time high yearly sales and pretty consistent the last 2 or 3?

Specially considering they have a old line up on key core models (LX, GX, IS, NX, RX)... And a much smaller model line up... I would call it a win honestly.
 

mikeavelli

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Isn't a bit hard to say "fall in America" when it's only around 10% less than the all time high yearly sales and pretty consistent the last 2 or 3?

Specially considering they have a old line up on key core models (LX, GX, IS, NX, RX)... And a much smaller model line up... I would call it a win honestly.

This. Title is trash and another trash YouTube video with an attention grabbing title.
 
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Isn't a bit hard to say "fall in America" when it's only around 10% less than the all time high yearly sales and pretty consistent the last 2 or 3?

Specially considering they have a old line up on key core models (LX, GX, IS, NX, RX)... And a much smaller model line up... I would call it a win honestly.
Falling is a little harsh because they're still #3. But its more of a drought of newer vehicles that sounded the alarm. IMO, they've kept their current buyers happy to keep their sales position despite their dropping marketshare (dropped for two straight years, 2016-18), but the need for better refreshed products to sell to conquest buyers and bring back previous owners (They are there) is becoming more apparent.

 

Will1991

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@Tragic Bronson , I won’t argue with that, but they seemed to eager to do their own version of “fall and rise” series from CNBC...

And to be honest, in my opinion CNBC jumped on a lot of “specialists” auto journalists (Who can’t even say eCVT for Toyota’s Hybrid Systems) and is doing a very good job in a new and in a refreshing way. In a way those “experts” weren’t able to come up, doing the same thing over and over...

Even Doug tried something similar with Infiniti.
 

LexsCTJill

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Well, surprise! Because I thought he was talking about Lexus, but you're talking about Toyota. ¯\_(ツ)_/¯

I use Toyota is the same way as I do Lexus. So when I say Toyota is trying to grow, meant to say Toyota is trying to grow Lexus. I believe Toyota is focused on all world markets for growth. Not just the US...is it the right move? No idea, US sales are steady but worldwide is growing.
 
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@Tragic Bronson , I won’t argue with that, but they seemed to eager to do their own version of “fall and rise” series from CNBC...

And to be honest, in my opinion CNBC jumped on a lot of “specialists” auto journalists (Who can’t even say eCVT for Toyota’s Hybrid Systems) and is doing a very good job in a new and in a refreshing way. In a way those “experts” weren’t able to come up, doing the same thing over and over...

Even Doug tried something similar with Infiniti.
I know, this quarantine is definitely causing a lot of the YT autosphere to find things to cover when they aren't able to go out and drive or get press vehicles. RR had success doing these with other brands like Hyundai/Kia and Acura, and it seems that the viewers like them, and will give suggestions to him on what brands to cover.

CNBC definitely pushed this a lot...I could definitely see them jump on this, and even Doug D as well. CNBC did trumpet the Camry and the Toyota brand, and they are probably less verse in the subject matter but they do interview industry folks. A lot of these R&F videos are probably what interests viewers and are good for metrics.

I use Toyota is the same way as I do Lexus. So when I say Toyota is trying to grow, meant to say Toyota is trying to grow Lexus.
I don't think you should do that, because the market for luxury brands isn't the same as regular mainline brands.

We discussed it here already, but probably it was before you jumped aboard. Toyota put its resources more towards the Big T than the L, and its definitely paying more dividends than at Lexus. Like I have always said, read the two Lexus books to get the best understanding of how the brand rose up and became what it is. This is reason why many loved the brand, and why the brand may have strayed away from its roots. I own both books, and I'm sure most of the senior guys here do as well; it would be good reading material again during this SAH order.

 
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