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      03-28-2008, 10:29 PM   #221
swamp2
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Thanks Wads for the data. Really appreciate taking the data and sharing. So don't get too bent when I tell you there are big problems using this data to get shift times. Unfortunately there is a serious consistency problem in the data. May be other problems as well that stem from sampling, smoothing or filtering. These do not give me any confidence in a shift time determination at all.

For instance lets take the MT case. Things are the easiest to discriminate there. How can it be that the clear change in acceleration level (the begining of the dip) at 1026.25 does not line up with the fairly clear change in slope in of the velocity curve, which looks very close to 1026.6? My definition of a shift would be from down turn in accleration to the next local peak or knee and I calculate that difference at 1.25 seconds for this case.

The curves by definition (acceleration and velocity) must be related by a simple time derivate and they are not. Something is wrong. On the positive side the general trends are visible and the maintenance of acceleration by DSG and its smoothness are without question and that is impressive and exactly as expected for a purposefully smoothed dual clutch set up.

Last edited by swamp2; 03-29-2008 at 12:31 AM.
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      03-29-2008, 04:42 AM   #222
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Originally Posted by T Bone View Post
Sure what do you want to bet on? Name the parameters. Seems to only way to shut you up is humilation.
Humiliation, will it match yours with regards to the M5 being quicker than the RS6. Check out SportAuto's results, you will find it's not me but you with egg on your face.

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Besides your technical inaccuracies, what idiot shifts mid corner under high lateral g loads? In any type of tranny?
As Bruce already said gearing and speed dictate whether you change gear midcorner, from experience I preferred an automatic as it's shift is velvety smooth and doesn't upset the balance of the chassis (road car are being discussed here), the surge that BMW are offering sound like a very bad idea for track use, such an effect WILL upset the chassis of this I am sure.

Now look at Wads graph for DSG, that is a perfectly smooth transition from one gear to the next, this is a gearbox which you could keep the throttle planted in a corner and shift with confidence. Once again proving that Audi understand what the technology should be used for.

P.S.
After seeing the DSG graph I would expect the S6 mode to have a slight dip during shift with a slight peak after shift, this will be the surge effect but there will be no improvement in acceleration only the feeling of being quicker.

P.S.
I will be glad to be proven wrong on this.

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      03-29-2008, 09:42 AM   #223
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Bruce,

Lets break this down to why sometimes you shift and other times you don't, again this is relating to either manual or SMG cars where there is a noticeable jerk/surge at change.

At slower speed corners the J/S (jerk/surge) will be most noticeable and will effect the balance most, on most occasions you (driver) must weigh up the benefits of whether to change down prior to the corner (one should never change down during corner) and possibly have to shift up during the corner while trying to smooth out the shift as best as possible (easier to do in a manual than SMG) or leave the car in the higher gear and have a more constant load on the chassis through the corner. On most cases I would almost always recommend the latter, you might not be the quickest through the corner but at least you should make it out the other side in one piece able the continue to fight for position.

The difference that DSG and hopefully DCT will bring to the race is the ability to change gear under load (throttle) during a corner without upsetting the chassis balance ie. without breaking traction, this will become more important on wet conditions where 400hp rwd chassis and only 50% weight load over the driven wheels will be a little edgy to say the least.

T-Bone,

It's a shame I didn't take that wager about the RS6 vs M5, at least you will have to pay up with the one you did take with that friend of yours. The really sad thing with some of you guys is that given a little track time and an education and you believe you know it all. Knowledge and ability are not the same thing in case you were wondering.
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      03-29-2008, 10:14 AM   #224
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Quote:
Originally Posted by footie View Post
Humiliation, will it match yours with regards to the M5 being quicker than the RS6. Check out SportAuto's results, you will find it's not me but you with egg on your face.

As Bruce already said gearing and speed dictate whether you change gear midcorner, from experience I preferred an automatic as it's shift is velvety smooth and doesn't upset the balance of the chassis (road car are being discussed here), the surge that BMW are offering sound like a very bad idea for track use, such an effect WILL upset the chassis of this I am sure.

Now look at Wads graph for DSG, that is a perfectly smooth transition from one gear to the next, this is a gearbox which you could keep the throttle planted in a corner and shift with confidence. Once again proving that Audi understand what the technology should be used for.
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\
T-Bone,

It's a shame I didn't take that wager about the RS6 vs M5, at least you will have to pay up with the one you did take with that friend of yours. The really sad thing with some of you guys is that given a little track time and an education and you believe you know it all. Knowledge and ability are not the same thing in case you were wondering.

Whoa tiger, The Sport Auto was not a heads up test. The only heads up test will be the M5board videos. I still bet on the M5. You want to go for glory and bet me now??

It was Enigma that answered it best, I was a bit harsh in calling you idiot but it does depend. I am not sure if Bruce has had a lot of torque in his track cars and it would have been a healthy debate.

The problem with arguing with you is that you have the technical prowess of a pre-pubescent girl and the emotions of a teenage girl in love with Audi.

Like I have offered, if you are in Kanada, you can ride bitch in my M6 and you can tell me if I should be shifting in some of the corners in high G loads....



You want to bet RS6 vs. M5 for the M5board videos?
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      03-29-2008, 11:30 AM   #225
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T-Bone,

I wouldn't bet on a one sided event like the M5Board outing. When two non-bias magazines have already found the RS6 the quicker with countless others to follows I think that should be enough for anyone to admit the Audi is the quicker.

I reckon I know more about how one should drive a car on track than you, if you think that your limited track experience earns you the right to comment on such things then who am I to argue.
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      03-29-2008, 03:18 PM   #226
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T-Bone,

I wouldn't bet on a one sided event like the M5Board outing. When two non-bias magazines have already found the RS6 the quicker with countless others to follows I think that should be enough for anyone to admit the Audi is the quicker.

I reckon I know more about how one should drive a car on track than you, if you think that your limited track experience earns you the right to comment on such things then who am I to argue.

Bet on the M5board. There have been no heads up tests between an M5 Saloon and RS6 where the RS6 has won. Are you afraid to bet on M5board videos? There are members here who can attest to see how fair these videos are.

Seems to me that you want to pull out your e-penis on track experience, it seems you have neither technical nor track experience. I am secure with my seat time and comments. At the very least, I don't always land on the losing side of the debates that you seem to land in.

Seriously, let me know if you ever make it to Toronto, I will take you around Mosport.

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      03-29-2008, 03:24 PM   #227
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I reckon I know more about how one should drive a car on track than you, if you think that your limited track experience earns you the right to comment on such things then who am I to argue.
Footie,

Do you have any video of you driving?
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      03-29-2008, 04:18 PM   #228
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Thanks Wads for the data. Really appreciate taking the data and sharing. So don't get too bent when I tell you there are big problems using this data to get shift times. Unfortunately there is a serious consistency problem in the data. May be other problems as well that stem from sampling, smoothing or filtering. These do not give me any confidence in a shift time determination at all.

For instance lets take the MT case. Things are the easiest to discriminate there. How can it be that the clear change in acceleration level (the begining of the dip) at 1026.25 does not line up with the fairly clear change in slope in of the velocity curve, which looks very close to 1026.6? My definition of a shift would be from down turn in accleration to the next local peak or knee and I calculate that difference at 1.25 seconds for this case.

The curves by definition (acceleration and velocity) must be related by a simple time derivate and they are not. Something is wrong. On the positive side the general trends are visible and the maintenance of acceleration by DSG and its smoothness are without question and that is impressive and exactly as expected for a purposefully smoothed dual clutch set up.
Heres the same shift without any smoothing applied to the curve.....
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      03-29-2008, 06:13 PM   #229
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Heres the same shift without any smoothing applied to the curve.....
I knew it. Looks like about 1/4 second deceleration. Thanks.
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      03-29-2008, 08:46 PM   #230
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Quote:
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Heres the same shift without any smoothing applied to the curve.....
It looks better here. It looks more like the begining of the shift is recognizable as beginning much closer at the same point in time on both curves. The acceleration trace looks like sampling right around 10 Hz. The velocity trace still has a lot of smoothing.

My estimation of the shift time, again based on the acceleration curve only is 0.8s +/- .2s (+/- .1 on each end). You can see this estimate does not yey even overlap with your initial estimate of .5 s (.48 s, as you said).

For M-DCT, especially under aggressive shifts under aggressive throttle we will need much better than 10 Hz resolution to time these particular shifts.

Thanks again! Really appreciate the input.
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      03-29-2008, 08:56 PM   #231
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Swamp,

I'm afraid I saw this coming. It seems it will take a serious professional (read expensive) piece of equipment to get the resolution needed to figure out how fast the M-DCT really is and to figure how some of the details of how this thing works. Thanks.
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      03-29-2008, 09:59 PM   #232
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Wow, I've somehow managed to miss out on this discussion! How did I do that?

Footie, T-Bone, Swamp, Enigma, Ersin, Wad. Thanks for keeping this thread interesting.

I am looking forward to seeing data on DCT although it will indeed be non-trivial to collect it. Forum members might not have access to the required instrumentation, but I am sure it will surface from somewhere eventually.
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      03-29-2008, 11:51 PM   #233
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Quote:
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...Yes, I understand what you are saying and I have not driven Mount Tremblant.....so equating this to tracks that I know.....
  • I would never shift at Mosports's 2nd and 4th corners
  • I would not shift through the essess at Watkins Glen
  • I would shift mid-way through the corner just before Fabi Straight at Shannoville
Look, saying you will shift during whatever corner and won't shift during another corner is just silly. You'll shift wherever the car dictates, and do whatever takes the lap time down.

Of course, there may be a corner where a particular car will dislike a shift badly enough so that lap times suffer. OK, don't shift during that corner with that car. You'll lose time there, but not money or blood.

I've never driven a high-torque car at real speed on a track (E36 M3, zero-torque Neon, chipped 1.8 GTI, E46 M3, SRT4), but fail to see how that can possibly make a difference. Perhaps you could explain. Don't refer to the obvious, though. Anybody can regulate their clutch and throttle feet.

Bruce

PS - Perhaps you could also explain your assertion that only idiots shift during a corner, combined with your statment that you will shift during a corner.
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      03-30-2008, 01:00 AM   #234
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Bruce,

You and I are fighting a losing battle against these guys.
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      03-30-2008, 01:12 AM   #235
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Bruce,

You and I are fighting a losing battle against these guys.
Nice try footie, but your statement above seems to be incorrect and a feeble team building effort.

1. There is not "these guys" disagreeing with you on the shift in corners issue, it is just TB.
2. Bruce does not appear to be on your side about anything other than this issue.
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      03-30-2008, 05:26 AM   #236
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Footie,

Do you have any video of you driving?

I do.

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      03-30-2008, 05:36 AM   #237
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mofomat,

Not my proudest day's racing.
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      03-30-2008, 05:36 AM   #238
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      03-30-2008, 05:38 AM   #239
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mofomat,

Not my proudest day's racing.

I thought "knob" was a bit harsh though.
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      03-30-2008, 05:46 AM   #240
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Nice try footie, but your statement above seems to be incorrect and a feeble team building effort.

1. There is not "these guys" disagreeing with you on the shift in corners issue, it is just TB.
2. Bruce does not appear to be on your side about anything other than this issue.
Not team building as such, I know that Bruce has also felt the weight over argument from you and others, as well as some other.

TB is someone who feels a need to argue for no other reason than the fact I currently drive an Audi and still rate them very highly indeed. Like most things he says he's usually wrong, the current argument being one of them as anyone with a decent amount of track experience will know.

The current discussion about surge and it possible unbalancing of the chassis if you shift during cornering is a very valid one and in my opinion one feature where DSG's smooth shift has an advantage. If like someone already said that BMW might have allowed for this in it's software programming then problem solved, but if not then I know I am right on this one. I

I admire your belief that BMW always know what they are doing, but if this was so then the recalls that occurred with the SMG and engine problems wouldn't have happened. No company always get it right, always keep that in mind.

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      03-30-2008, 11:11 AM   #241
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Look, saying you will shift during whatever corner and won't shift during another corner is just silly. You'll shift wherever the car dictates, and do whatever takes the lap time down.

Of course, there may be a corner where a particular car will dislike a shift badly enough so that lap times suffer. OK, don't shift during that corner with that car. You'll lose time there, but not money or blood.

I've never driven a high-torque car at real speed on a track (E36 M3, zero-torque Neon, chipped 1.8 GTI, E46 M3, SRT4), but fail to see how that can possibly make a difference. Perhaps you could explain. Don't refer to the obvious, though. Anybody can regulate their clutch and throttle feet.

Bruce

PS - Perhaps you could also explain your assertion that only idiots shift during a corner, combined with your statment that you will shift during a corner.

As I noted, I was being a bit harsh calling people idiots for shifting in a corner, as I will do it too in low g corners.

If my car is at the limit in the middle of a corner, I will keep steady throttle until I have some margin for the car to unsettle during any shift, manual or otherwise. The corners I listed where I won't shift, I absolutely do not want to upset the car's balance. The one corner where there is a high G load, and where I will shift is a slower corner and there is more room for correction.

Having a high torque car multiples the effects of loading and unloading the rear end for shifts.
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      03-30-2008, 11:15 AM   #242
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TB is someone who feels a need to argue for no other reason than the fact I currently drive an Audi and still rate them very highly indeed. Like most things he says he's usually wrong, the current argument being one of them as anyone with a decent amount of track experience will know.

Where did I bring up Audi here? You love to mask your lack of technical knowledge with mysticism and bullshit. I will gladly admit when I am wrong when there is data..... You have no data, you have this dogmatic belief in DSG and a dogmatic hatred of MDCT.

At the end of the day, I don't think you are a bad guy, hell I would love to have a couple of pints with you. But this is a techical discussion and people will propose theories with data support.
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