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      07-29-2008, 02:07 PM   #23
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Originally Posted by swamp2 View Post
Yeah, you are right, I haven't read anything about transmissions and DCTs Please just humor us all with your proof any any DCT transmission other than the GT-R shifting in 140-200 ms. As well we need to know if the figure includes clutching only or any potential delay after paddle.
Couldn't lay my hands on the PDK spec sheet at the moment but I when on a hunt info to provide you with I found this quote from a guy called Kerso F1, he stated that the shift for the new Audi and the M-DCT. Here's his quote,

Quote:
Do you know Nissan GT-R shifting speed? 200ms...

Do you know new Audi 7Speed S Tronic shifting speed(the one that will be in new S4)? 200ms...

Do you know M3 M-DKG shifting speed? 160ms...

All speeds are for complete shifting process...
This is why myself and others which have sampled DSG and the M-DCT say the delay is less with the BMW system, it's 40ms quicker to complete the whole process.

And here's the link

http://www.rennteam.com/showflat.php...r=449592&page=

I just wished I could find that spec sheet, I will have to ask for another copy and scan it for you.

As for the other part of your request I don't see the point as no matter which I say you will disagree, as per normal. The only thing I am interested in is the knowledge that I know I am correct.

P.S.

To back up Kerso F1 and my claims of the 200ms for Audi, there's some link.

http://www.worldcarfans.com/9080604....etails-surface
http://www.autoblog.com/2008/06/03/p...percharged-s4/
http://www.carmagazine.co.uk/News/Se...s/?&R=EPI-6149
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      07-29-2008, 03:57 PM   #24
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Quote:
Originally Posted by footie View Post
Couldn't lay my hands on the PDK spec sheet at the moment but I when on a hunt info to provide you with I found this quote from a guy called Kerso F1, he stated that the shift for the new Audi and the M-DCT. Here's his quote,



This is why myself and others which have sampled DSG and the M-DCT say the delay is less with the BMW system, it's 40ms quicker to complete the whole process.

And here's the link

http://www.rennteam.com/showflat.php...r=449592&page=

I just wished I could find that spec sheet, I will have to ask for another copy and scan it for you.

As for the other part of your request I don't see the point as no matter which I say you will disagree, as per normal. The only thing I am interested in is the knowledge that I know I am correct.

P.S.

To back up Kerso F1 and my claims of the 200ms for Audi, there's some link.

http://www.worldcarfans.com/9080604....etails-surface
http://www.autoblog.com/2008/06/03/p...percharged-s4/
http://www.carmagazine.co.uk/News/Se...s/?&R=EPI-6149
Excellent sources, largely online journalists and other miscellaneous forum members with completely unknown credibility.

That fellow from Croatia does not know the DCT shift time at 160ms. If anyone knew it in the world (outside of BMW) it is likely enigma.

Quote:
It must be true I read in on the interweb


Recall these important details on shift times. You really should know this by now...

1. Shift times for DCs vary by gear and rpm
2. Quoted shift times may or may not include the lag and are not very meaningful without qualifying that.
3. Some manufacturers quote max times with lag, other quote minimums without lag. Again numbers are a bit meaningless without qualifications/clarifications.

Oh and always, ust like you do 100% of the time avoid the direct questions which ask you to precisely state you case about something technical. You just can't do it. I find it mildly entertaining. Hence half of my banter with you. Save the technical topics for the big boys.

Keep up the good work foot.
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      07-29-2008, 05:40 PM   #25
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Well if enigma knows then why isn't he sharing it with the rest of us. The figure I was told for the Audi setup is currently 200ms, in the buff on the Porsche says the same thing and Nissan also say the same. That's three out of the five companies currently selling DCT transmissions, the odds are sort of stacked in my favour don't you think.

With the exception of this guy Kerso F1 the rest are very respected outfits with a long history for accurate info on future developments. I am only providing you with evidence that the knowledge of these things are out there and are the same as I already know, if you disregard them as you do with most things that don't fit in swampie's ideal world then that's your problem not mine.
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      07-29-2008, 08:04 PM   #26
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Quote:
Originally Posted by footie View Post
Well if enigma knows then why isn't he sharing it with the rest of us. The figure I was told for the Audi setup is currently 200ms, in the buff on the Porsche says the same thing and Nissan also say the same. That's three out of the five companies currently selling DCT transmissions, the odds are sort of stacked in my favour don't you think.

With the exception of this guy Kerso F1 the rest are very respected outfits with a long history for accurate info on future developments. I am only providing you with evidence that the knowledge of these things are out there and are the same as I already know, if you disregard them as you do with most things that don't fit in swampie's ideal world then that's your problem not mine.
Enigma said he is processing some track data to further share the detials with us.

Let me summarize all of what you know about DCT shift times:

-Nissan says 200ms, ZERO qualification as to what is really means
-Some web sites say 200ms for VAG, ZERO qualification as to what is really means
-Some random user says 160ms for BMW, again no qualification, getting the pattern here....

Don't get me wrong, I do believe that including lag, syncro movement and both clutch operations most DCTs are in the 200ms ballpark but that is qualfied and far from solid proof. I also think this is a worst case type of spec. WOT near redline, 5->6 will be CONSIDERABLY faster.
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      07-29-2008, 08:40 PM   #27
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Given the level of interest in shift times, I am surprised that a respectable magazine still has not come up with a more sensitive setup to measure the accelerations of different DC cars during shifting. It's not rocket science, and it's a just a matter of someone having the will to put together a system with the required frequency response. What kind of accelerometers do the current motorsport-related data acquisition systems utilize by the way? I assume measuring the delay would require tapping into the wiring of the shifter to detect the input signal.
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      07-29-2008, 11:22 PM   #28
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Originally Posted by lucid View Post
Given the level of interest in shift times, I am surprised that a respectable magazine still has not come up with a more sensitive setup to measure the accelerations of different DC cars during shifting. It's not rocket science, and it's a just a matter of someone having the will to put together a system with the required frequency response. What kind of accelerometers do the current motorsport-related data acquisition systems utilize by the way? I assume measuring the delay would require tapping into the wiring of the shifter to detect the input signal.
I speced out a system to do it including a fancy tri-axial accel (to also get suspension data and g forces) and a DAQ. I was going to be quite conservative on the sampling rate to not only get shift times but shift dynamics during the shift. It was almost $1k. Not worth it to me just for fun. Took a bit more research and engineering type shopping than most rags would be capable of. I did say I would take donations, share all the results and test multiple vehicles but there are only a few of us techie enough to be really interested.

Last edited by swamp2; 07-30-2008 at 01:59 AM.
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      07-30-2008, 02:24 AM   #29
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Originally Posted by swamp2 View Post
I speced out a system to do it including a fancy tri-axial accel (to also get suspension data and g forces) and a DAQ. I was going to be quite conservative on the sampling rate to not only get shift times but shift dynamics during the shift. It was almost $1k. Not worth it to me just for fun. Took a bit more research and engineering type shopping than most rags would be capable of. I did say I would take donations, share all the results and test multiple vehicles but there are only a few of us techie enough to be really interested.
Some guys I know say it almost impossible to accurately measure the time of the shift but have place a ball park figure of between 6~12ms.

I posted a video of a Fifthgear review of the DSG and around 1:12s in they show a cut away of the gearbox doing a shift. Here's it again.



Remember the gears overlap a bit that is why you feel no drop off in acceleration and why the shift is in the low milliseconds.
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      07-30-2008, 05:37 AM   #30
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Quote:
Originally Posted by footie View Post
Some guys I know say it almost impossible to accurately measure the time of the shift but have place a ball park figure of between 6~12ms.
Foot, really, leave the technical topics to the big dogs...

You are aware that modern scientific equipment can measure picoseconds. This is only a billion times faster . Pretty crude accelerometers can EASILY measure single ms.
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      07-30-2008, 06:08 AM   #31
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Originally Posted by swamp2 View Post
Foot, really, leave the technical topics to the big dogs...

You are aware that modern scientific equipment can measure picoseconds. This is only a billion times faster . Pretty crude accelerometers can EASILY measure single ms.
The problem I am referring to it the overlap between gears. Different people will have different thoughts on where the shift actually starts and finishes. I give you a figure (6~12ms) to work on, it would be interesting to know if that info is correct.

As you rightly say the technical stuff is your field and I appreciate your input if always a little anal.
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      07-30-2008, 09:21 AM   #32
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Quote:
Originally Posted by footie View Post
The problem I am referring to it the overlap between gears. Different people will have different thoughts on where the shift actually starts and finishes. I give you a figure (6~12ms) to work on, it would be interesting to know if that info is correct.
It will be pretty obvious when you look at the charts and see the acceleration drop when the torque drops. There will be two reasons for the drop in torque (excluding any torque curve and transient inertia related effects): the drop in gearing and the clutches disengaging/engaging. The former can be separated from the latter as the former should result in a permanent and somewhat stable offset in the acceleration reading. It would be almost impossible to perfectly overlap the clutch engagement/disengagement, and if you get it wrong, you'll end up with excess clutch wear. It wouldn't make sense to go for it although they probably went for a partial overlap in the more agressive settings. It is easy to pick up a sensor that operates at the 10 kHz range. That means it would take a measurement every 1/10000 of a second, which should be enough resolution for this task.
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      07-30-2008, 09:49 AM   #33
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Quote:
Originally Posted by swamp2 View Post
I speced out a system to do it including a fancy tri-axial accel (to also get suspension data and g forces) and a DAQ. I was going to be quite conservative on the sampling rate to not only get shift times but shift dynamics during the shift. It was almost $1k. Not worth it to me just for fun. Took a bit more research and engineering type shopping than most rags would be capable of. I did say I would take donations, share all the results and test multiple vehicles but there are only a few of us techie enough to be really interested.
I'd be interested in working with you on this. I can chip in to support the cost. If we can get 10-15 people to chip in, this might be a go.
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      07-30-2008, 02:04 PM   #34
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Originally Posted by lucid View Post
I'd be interested in working with you on this. I can chip in to support the cost. If we can get 10-15 people to chip in, this might be a go.
I did post the suggestion that I would take donations. 10 people would be fine at <100 per person. I just don't think the folks here are techie enough to donate $100. Let's see what enigma has for us and go from there....
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      07-31-2008, 03:25 PM   #35
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I did post the suggestion that I would take donations. 10 people would be fine at <100 per person. I just don't think the folks here are techie enough to donate $100. Let's see what enigma has for us and go from there....
^ Nice way to end a very lively thread. Talk real tech and ask for money. No better way to KILL a thread. This is quite funny to me.
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      07-31-2008, 05:15 PM   #36
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^ Nice way to end a very lively thread. Talk real tech and ask for money. No better way to KILL a thread. This is quite funny to me.
Swamp, this is hardly big-deal tech - it's just money. You need to find nine folks who are on the fence with their future purchase, and their indecision must lie with just how much quicker the, ahem, automatic actually is. In addition, they'd probably want to know about comparative launch effectiveness in return for their hard-earned money, so I mean quicker in terms of just how many car-lengths separate the two out on the mean streets. These questions will likely be answered in the fullness of time thru additional comparison tests, etc., so folks who don't feel an urgent purchase need will likely pass on this. People who do track days will likely pass for at least a while, as well.

Next round of data begins when the CTS-V hits the streets.

I personally would like to have a handle on all this, because I think one of these types of transmissions will eventually lure me over to the dark side of two-pedal driving. I'm willing to wait, however.

Bruce

Edit: PS - Not that I'm particularly interested in starting another grumbling back-and-forth between us, but you're not the right guy to do this test, anyway. I know you pride yourself on objectivity, but your obvious bias has shown up in this thread and others. You know - things like accusing folks of bias if they have anything less than positive to say about the M-DCT box, etc.

2nd edit: OK, lucid's right. I take that last back.

Last edited by bruce.augenstein@comcast.; 07-31-2008 at 05:54 PM. Reason: That lucid guy
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      07-31-2008, 05:39 PM   #37
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Bruce, it is clear that Swamp really likes his DCT, and maybe gets a bit carried away with his excitement for it at times, but when it comes to collecting and posting raw data, I am sure that he would do the right thing (I am sure you would as well). Interpretation of the data is another matter, and then we might all have disagreements depending on how clean the data are, and biases can play into that as they always do—happens in scientific/academic circles all the time. So, I don't see a problem with setting up a collective pot to do some testing around here. I doubt the mags will do the kind of testing we would like as the results would not have any significant implications for their broader audience.
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      07-31-2008, 05:50 PM   #38
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Quote:
Originally Posted by lucid View Post
Bruce, it is clear that Swamp really likes his DCT, and maybe gets a bit carried away with his excitement for it at times, but when it comes to collecting and posting raw data, I am sure that he would do the right thing (I am sure you would as well). Interpretation of the data is another matter, and then we might all have disagreements depending on how clean the data are, and biases can play into that as they always do—happens in scientific/academic circles all the time. So, I don't see a problem with setting up a collective pot to do some testing around here. I doubt the mags will do the kind of testing we would like as the results would not have any significant implications for their broader audience.
Points made - each and every one.
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      07-31-2008, 06:01 PM   #39
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I personally don't see the point in such an exercise, though if it was carried out my curiousity would be pricked a little.

My point is, we all know it's zero lose in momentum, every manufacturer says as much and it's exact how it feels when driving it. There's also numerous videos on Youtube between GTi Golf with and without DSG racing and you see each and every gear shift the DSG car pulls yards out of the manual.

If it proved to be 6ms or 30ms, would such a thing make or break someone buying it. Somehow I doubt it.
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      07-31-2008, 06:33 PM   #40
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Somebody buy this.... Does the iPhone accelerometer have the resolution to measure what we want?

http://dynolicious.com/index.html
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      07-31-2008, 07:55 PM   #41
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Quote:
Originally Posted by swamp2 View Post
I speced out a system to do it including a fancy tri-axial accel (to also get suspension data and g forces) and a DAQ. I was going to be quite conservative on the sampling rate to not only get shift times but shift dynamics during the shift. It was almost $1k. Not worth it to me just for fun. Took a bit more research and engineering type shopping than most rags would be capable of. I did say I would take donations, share all the results and test multiple vehicles but there are only a few of us techie enough to be really interested.
Not sure if they can be adapted, but I have two accelerometers from an extra correlator unit that I could let you use...

PM me the type you are looking at/would like to use.
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      07-31-2008, 11:51 PM   #42
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Quote:
Originally Posted by bruce.augenstein@comcast. View Post
Swamp, this is hardly big-deal tech - it's just money. You need to find nine folks who are on the fence with their future purchase, and their indecision must lie with just how much quicker the, ahem, automatic actually is. In addition, they'd probably want to know about comparative launch effectiveness in return for their hard-earned money, so I mean quicker in terms of just how many car-lengths separate the two out on the mean streets. These questions will likely be answered in the fullness of time thru additional comparison tests, etc., so folks who don't feel an urgent purchase need will likely pass on this. People who do track days will likely pass for at least a while, as well.

Next round of data begins when the CTS-V hits the streets.

I personally would like to have a handle on all this, because I think one of these types of transmissions will eventually lure me over to the dark side of two-pedal driving. I'm willing to wait, however.

Bruce

Edit: PS - Not that I'm particularly interested in starting another grumbling back-and-forth between us, but you're not the right guy to do this test, anyway. I know you pride yourself on objectivity, but your obvious bias has shown up in this thread and others. You know - things like accusing folks of bias if they have anything less than positive to say about the M-DCT box, etc.

2nd edit: OK, lucid's right. I take that last back.
1. Agreed that accelerometers even high frequency tri-ax ones are not particularly high tech, but they are high tech for this crowd.

2. Your bias against me is clearly evident and offensive. I would probably be THE best guy here to do testing like this. Nice try to take your words back but still really lame in the end. Why is it that you just can not believe that to me the truth and understanding are infinitely more important than brands and loyalty. You just do not know me, not yet, not after all of our banter, not one iota.

Thanks lucid!

OC: We need at least 500 Hz capability and DC capability as well. The accels and data acquisition system both have to be capable at this frequency.

Foot: There is a loss in momentum with a DC, just really small (i.e. it is not zero loss).
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      08-01-2008, 12:31 AM   #43
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Quote:
Originally Posted by T Bone View Post
Somebody buy this.... Does the iPhone accelerometer have the resolution to measure what we want?

http://dynolicious.com/index.html
I bought it to try it out. The iPhone accelerometers sample at 100Hz I think. When doing an acceleration run, it does draw a small graph showing the G forces, but it does not save it. So one might be able to get an idea by the shape of the acceleration G's line if you saved a screenshot right after a run. But it's a pretty small graph.

A better way would be to use a track data acquisition system such as a Traqmate or G2X which would store the data and allow later analysis and viewing. I have a G2X, it appears that the sampling rate is about 100Hz.

I've attached two screenshots which show my data traces around an upshift. The Laguna one is in my GT3 (MT, not rushing), the Sears one is in my E46 M3 with SMG. Red line is engine RPMs, blue line is speed as measured by GPS, and green is longitudinal (acceleration G's). [oops, didn't realize the pix don't show the filenames, Laguna is the top one with a "3" in the window tab near the top center, the Sears SMG one is the one with a "10"]

I think by looking at the shape of the green line, we might get a better idea, the resolution should be enough to get a better idea and comparison of MT vs DCT. Maybe not high enough resolution to accurately measure if the shift is 6 or 30ms though? But perhaps getting some data recorded with one of these might provide some insights.
Attached Images
  
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      08-01-2008, 01:57 AM   #44
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Quote:
Originally Posted by swamp2 View Post
Foot: There is a loss in momentum with a DC, just really small (i.e. it is not zero loss).

To quote from BMW's own press release 'The M-DCT transmission with Drivelogic shifts gears without the slightest interruption in the flow of power', zero lose in power means zero lose in forward momentum.

You can't preach one part of the press release to me (how the surge was created) and disregard the rest just because you disagree with it. If you prove there is a lose in momentum then that proves that what BMW wrote was wrong, and that might include the rest of their release (surge) as well.
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