Sluggish shifts in M mode.....
05-11-12, 01:13 PM
#16
Not necessarily. Look, my M3 had the DCT and my Maser had the F1 tranny, and both blipped on downshifts even under 2k rpm. Now both were automated manual tranny’s vs. the automatic 8 speed in the ISF, but if Lexus went as far as rev matching the downshifts, why not offer it in all RMP range??
I’m sure I’m not the only one that finds this annoying. With that said, I’m new to this car, and if this is normal operation, is a tune available that would add the blips to entire rpm range including between 1-2k.
I’m sure I’m not the only one that finds this annoying. With that said, I’m new to this car, and if this is normal operation, is a tune available that would add the blips to entire rpm range including between 1-2k.
05-11-12, 02:36 PM
#17
Lexus Test Driver
Not necessarily. Look, my M3 had the DCT and my Maser had the F1 tranny, and both blipped on downshifts even under 2k rpm. Now both were automated manual tranny’s vs. the automatic 8 speed in the ISF, but if Lexus went as far as rev matching the downshifts, why not offer it in all RMP range??
I’m sure I’m not the only one that finds this annoying. With that said, I’m new to this car, and if this is normal operation, is a tune available that would add the blips to entire rpm range including between 1-2k.
I’m sure I’m not the only one that finds this annoying. With that said, I’m new to this car, and if this is normal operation, is a tune available that would add the blips to entire rpm range including between 1-2k.
I know what you mean and I have no idea why it operates the way it does, must have been a decision made by an engineer at Toyota. Honestly I don't believe the transmission has to do ANY throttle blips, seeing as it is a standard automatic with a torque converter. I believe the blip is more of a marketing feature to "thrill" the senses when making high rev downshifts.
05-11-12, 08:49 PM
#19
Sounds normal for sure.
But what has made me wonder about things is, I believe, the variable valve timing. There are times when I'll ease off the gas and the rpms will drop slightly, but then drop even further. Or the opposite where around 2500rpm or so I don't feel a hesitations but there is a slight "meh" when giving casual acceleration.
Full WOT neither of these are issues...it's just the pedestrian cruising where I can tell the car isn't being driven as hard as it desires lol.
But what has made me wonder about things is, I believe, the variable valve timing. There are times when I'll ease off the gas and the rpms will drop slightly, but then drop even further. Or the opposite where around 2500rpm or so I don't feel a hesitations but there is a slight "meh" when giving casual acceleration.
Full WOT neither of these are issues...it's just the pedestrian cruising where I can tell the car isn't being driven as hard as it desires lol.
05-12-12, 07:31 AM
#20
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I know what the OP means about M3 blipping downshift on everything. I was in one recently and it sounded nice. My ISF is my first automatic and I wished it blipped everywhere in the rev range. I heel and toed everywhere in my manual V8 S4 and it sounded great.
Granted the F sounds epic in the higher rev range on downshift but down low its very tame.
I find it hard to cruise sedately in my F. I hate the car for being sluggish and sloppy. It's indecisive and clumsy with throttle response and gear changes. So mines in sport manual/auto most of the time apart from startup. The only problem is in that mode is that it needs to be driven aggressively which will cost my licence I'm sure.
Granted the F sounds epic in the higher rev range on downshift but down low its very tame.
I find it hard to cruise sedately in my F. I hate the car for being sluggish and sloppy. It's indecisive and clumsy with throttle response and gear changes. So mines in sport manual/auto most of the time apart from startup. The only problem is in that mode is that it needs to be driven aggressively which will cost my licence I'm sure.
12-01-12, 08:22 PM
#21
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I have also been experiencing sluggish or rather laggy shifts while in M mode. I test drove 2 used ISF's before purchasing a new 2012, and while in sport mode in Manual, i was amazed at how fast and SMOOTH the car shifted gears. With my new car however, i have been experiencing laggish response times while shifting gears in M mode. It's difficult to describe, but its like my body is being jolted around when shifting, almost as if I'm briefly letting of the acceleration when shifting (which of course I'm not). And when the car is in sport mode and in Auto, the car seems to stay in high gears way too long before shifting to the next gear. So basically I've been driving in auto non-sport mode always because thats the only way my car shifts smoothly...
12-02-12, 05:29 PM
#22
Not necessarily. Look, my M3 had the DCT and my Maser had the F1 tranny, and both blipped on downshifts even under 2k rpm. Now both were automated manual tranny’s vs. the automatic 8 speed in the ISF, but if Lexus went as far as rev matching the downshifts, why not offer it in all RMP range??
I’m sure I’m not the only one that finds this annoying. With that said, I’m new to this car, and if this is normal operation, is a tune available that would add the blips to entire rpm range including between 1-2k.
I’m sure I’m not the only one that finds this annoying. With that said, I’m new to this car, and if this is normal operation, is a tune available that would add the blips to entire rpm range including between 1-2k.
Why would we need blips at 1-2k rpm?
12-02-12, 06:12 PM
#23
Tech Info Resource
iTrader: (2)
Originally Posted by http://www.n54tech.com/forums/showthread.php?t=7902
Now, here is actual documentation to support shift speeds and the reason why a dual clutch transmission simply can not be approached by an automatic or manual.
A dual clutch transmission is essentially two manual transmissions in one housing. One gear set is responsible for odd gears and one gear set is responsible for even gears. The next gear is essentially already preselected. When one gear set is disengaged, the other is already in gear and it is basically an instantaneous shift with no perceivable interruption. It happens forty times faster than the blink of an eye.
The VW group has their DSG numbers published and they are 8 milliseconds. Basically, a human being can not even perceive the gear change.
The fastest automatic in the world is the Lexus IS-F gearbox, at 100 ms. The ZF transmission in BMW's is at the 200 ms mark.
Unfortunately, a person with extreme bias posted numbers without realizing what they were posting or willing to admit reality, skewing numbers to misrepresent the facts due to personal issues.
Well, here are the numbers with support.
A long shift time is considered anything over 625 ms
The average manual car driver: 500 ms - 1 s
Aston Martin Vanquish: 250 ms
Ferrari 575M: 220 ms
BMW M3 E36 with SMG I: 220 ms
Ferrari 360: 150 ms
Enzo Ferrari: 150 ms
Lexus LFA: 150 ms
Ferrari FXX: Under 100 ms
Nissan GT-R: 100ms
BMW M3 E46 with SMG II: 80 ms
Ferrari 430 Scuderia & FXX Evoluzione: 60 ms
Volkswagen Golf GTI (Direct Shift): 8 ms
Bugatti Veyron (Direct Shift): 8 ms
All Volkswagen DSG Gearbox (Direct Shift): 8 ms
The source for shift times as well as DSG information is here if one is interested: http://paultan.org/2006/06/26/vw-pha...s-way-for-dsg/ (sorry, dead link)
BMW has not posted official shift times for the DCT unfortunately. Why not? Getrag just hasn't released the info officially but 4 ms has been posted as a "leak" on M3post.
The Nissan GTR time is stated odd and I believe it is simply due to how Nissan explains it cutting the shift time in R mode vs. regular mode. The GR6 Borg Warner tranny is not shifting slower than sequential manuals, just does not make sense. Maybe it is 100 ms though, but that would just be odd.
Just how big of a difference does the DCT make? Even vs. the best auto transmission in the world for shift speed, it will be picking up a conservative tenth per shift. What about vs. a manual? Well, here is a professional driver in a manual car vs. the same car in DSG, see for yourself:
A dual clutch transmission is essentially two manual transmissions in one housing. One gear set is responsible for odd gears and one gear set is responsible for even gears. The next gear is essentially already preselected. When one gear set is disengaged, the other is already in gear and it is basically an instantaneous shift with no perceivable interruption. It happens forty times faster than the blink of an eye.
The VW group has their DSG numbers published and they are 8 milliseconds. Basically, a human being can not even perceive the gear change.
The fastest automatic in the world is the Lexus IS-F gearbox, at 100 ms. The ZF transmission in BMW's is at the 200 ms mark.
Unfortunately, a person with extreme bias posted numbers without realizing what they were posting or willing to admit reality, skewing numbers to misrepresent the facts due to personal issues.
Well, here are the numbers with support.
A long shift time is considered anything over 625 ms
The average manual car driver: 500 ms - 1 s
Aston Martin Vanquish: 250 ms
Ferrari 575M: 220 ms
BMW M3 E36 with SMG I: 220 ms
Ferrari 360: 150 ms
Enzo Ferrari: 150 ms
Lexus LFA: 150 ms
Ferrari FXX: Under 100 ms
Nissan GT-R: 100ms
BMW M3 E46 with SMG II: 80 ms
Ferrari 430 Scuderia & FXX Evoluzione: 60 ms
Volkswagen Golf GTI (Direct Shift): 8 ms
Bugatti Veyron (Direct Shift): 8 ms
All Volkswagen DSG Gearbox (Direct Shift): 8 ms
The source for shift times as well as DSG information is here if one is interested: http://paultan.org/2006/06/26/vw-pha...s-way-for-dsg/ (sorry, dead link)
BMW has not posted official shift times for the DCT unfortunately. Why not? Getrag just hasn't released the info officially but 4 ms has been posted as a "leak" on M3post.
The Nissan GTR time is stated odd and I believe it is simply due to how Nissan explains it cutting the shift time in R mode vs. regular mode. The GR6 Borg Warner tranny is not shifting slower than sequential manuals, just does not make sense. Maybe it is 100 ms though, but that would just be odd.
Just how big of a difference does the DCT make? Even vs. the best auto transmission in the world for shift speed, it will be picking up a conservative tenth per shift. What about vs. a manual? Well, here is a professional driver in a manual car vs. the same car in DSG, see for yourself:
12-02-12, 06:59 PM
#25
Tech Info Resource
iTrader: (2)
Finally - confirming - the transmission is absolutely limited in what it will do when the engine is cold - the Factory Service Manual says the transmission is inhibited from shifting into 4th, 5th, 6th, 7th, and 8th based on THW, the engine coolant temperature sensor signal. While there is definitely an ATF temperature sensor, it is not used to determine whether the gearbox will shift or not, and there is a very lengthy explanation of how the TCU micro-modulates pressure in the gearbox based on ATF temperature. So Lexus has not seen fit to restrict us from using higher gears except when the engine itself is cold. This is very different from the 6 speed autos in the other 2IS. They are not allowed to engage higher gears until the ATF is up to temperature. I can only assume this is because those gearboxes do not have the software to manage the clutch pressures the way the AA80E does.
12-03-12, 08:13 AM
#26
Lexus Champion
Not necessarily. Look, my M3 had the DCT and my Maser had the F1 tranny, and both blipped on downshifts even under 2k rpm. Now both were automated manual tranny’s vs. the automatic 8 speed in the ISF, but if Lexus went as far as rev matching the downshifts, why not offer it in all RMP range??
I’m sure I’m not the only one that finds this annoying. With that said, I’m new to this car, and if this is normal operation, is a tune available that would add the blips to entire rpm range including between 1-2k.
I’m sure I’m not the only one that finds this annoying. With that said, I’m new to this car, and if this is normal operation, is a tune available that would add the blips to entire rpm range including between 1-2k.
12-03-12, 08:43 AM
#27
Yeah same here. I would recommend leaving it in auto until warm. Theres no benefit or enjoyment having it in manual before it has reached its operating temperature...Im not questioning your driving expertise, but you probably don't want to ruin the tranny.
But yeah to my knowledge all isf's experience what you are experiencing.
But yeah to my knowledge all isf's experience what you are experiencing.
12-03-12, 04:44 PM
#28
I don't think this is accurate. DCT gearboxes shift way faster than anything else available including our F. The F at 100msec is no match for the VW DSG at 8 msec. No fanboi here, just stating facts as documented by any number of sources.
Here's why I call manual shift cars dinosaurs.
Here's why I call manual shift cars dinosaurs.
12-03-12, 05:13 PM
#29
Tech Info Resource
iTrader: (2)
Yes, I agree, it's far quicker than I am, and every time I drive my 6 speed Supra I am reminded of how much better a computer can shift gears.
12-04-12, 09:11 AM
#30
The SMG M3 for sure. Keep in mind, there's also a 200 msec "preparation time" for the F to shift. It's pretty well documented. Of course the marketing people latched on to the 100 msec actual shift time, but the F really does take 300 msec total from the time you hit the switch until the gear change is complete.
Yes, I agree, it's far quicker than I am, and every time I drive my 6 speed Supra I am reminded of how much better a computer can shift gears.
Yes, I agree, it's far quicker than I am, and every time I drive my 6 speed Supra I am reminded of how much better a computer can shift gears.
It begs the question: how many of these have omitted preparation times?
I suspect many of them.