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      03-04-2007, 04:51 PM   #45
T Bone
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Originally Posted by Trpltrbl View Post
YES, I am sure BMW will take care of that right away, for the few M3 track junkies that will buy the car for track use.
If you really think that, you might have a problem.....

A good transmission can be used on the track and the street.....there are some problems with VW's DSG that BMW would need to fix before they bring it into production.

Do you have a lot of experience with this marque?
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      03-05-2007, 05:12 AM   #46
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Originally Posted by T Bone View Post
The DSG is a nice pseudo replacement for an automatic transmission but not suited for spirited driving and certainly not on a track. Do some searches......
  • You cannot skip gears downshifting - i.e. 5 to 3rd, 6th to 3rd - this makes it useless around a track
  • Also, people complain that it kicks down regardless if it is in auto / manual mode when you go part throttle - no control
If BMW does a DSG type of system, I suspect they would need to fix these 2 issues....
The 1st point you make is flat wrong. Sequential gearboxes like those used in, say, race cars, cannot skip gears either. Seems like those F1 cars do just fine going in order.

Your 2nd point is simply a line in the software and can be fixed.
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      03-05-2007, 09:10 AM   #47
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Originally Posted by enigma View Post
The 1st point you make is flat wrong. Sequential gearboxes like those used in, say, race cars, cannot skip gears either. Seems like those F1 cars do just fine going in order.

Your 2nd point is simply a line in the software and can be fixed.

On skipping gears, I seem to be able to skip a couple of gears in my SMG3. I am not certain how this happens, whether they engage the clutch or not but with DSG, as I understand it, you must engage the clutch and the sequential gear.

If it is just a line or 2 of code, why hasn't VW fixed it, probably because it reveals compromises else where.
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      03-05-2007, 03:04 PM   #48
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On skipping gears, I seem to be able to skip a couple of gears in my SMG3. I am not certain how this happens, whether they engage the clutch or not but with DSG, as I understand it, you must engage the clutch and the sequential gear.

If it is just a line or 2 of code, why hasn't VW fixed it, probably because it reveals compromises else where.
True race cars have to engage the drive in every gear. Yet they seem to do just fine on race tracks.

As to the SW, its a design issue. VW has just decided they want the auto shifting. Yes its a compromise, but its one to keep the non hard core drivers happy Its not a mechanical limitation.
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      03-05-2007, 05:09 PM   #49
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Why would you need to skip a gear on the track with a SMG gearbox? You can downshift so quickly with the SMG there's no need to skip a gear. Just use the engine braking to assist in slowing you for the next corner.
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      03-05-2007, 05:13 PM   #50
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Why would you need to skip a gear on the track with a SMG gearbox? You can downshift so quickly with the SMG there's no need to skip a gear. Just use the engine braking to assist in slowing you for the next corner.
There isn't a reason to skip gears. You shift while you are on the brakes and you have plenty of time to get to whatever gear you need.
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      03-05-2007, 05:23 PM   #51
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Originally Posted by skierman64 View Post
Why would you need to skip a gear on the track with a SMG gearbox? You can downshift so quickly with the SMG there's no need to skip a gear. Just use the engine braking to assist in slowing you for the next corner.

On the track if you are transitioning from a highspeed straight into a relatively tight corner, you may need to drop 2 gears so you can accelerate out of the apex. I am going to take my M6 on the track this summer and I am going to look forward to revisitng some corners where I had difficulty going through 2 gears using heel-n-toe in the past.

Even on the street, if you are cruising around in 7th gear, you need to get to 3rd or 4th to accelerate on the highway.
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      03-05-2007, 05:26 PM   #52
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I think the circumstance where one would want to be able to truly skip gears is this: Cruising in 7th gear, at normal to slow highway speeds then wanting to have immediate and maximum acceleration. Typically you would want 3rd or 4th gear skipping all others. I have not tried this much myself with SMG.
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      03-05-2007, 05:47 PM   #53
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T-bone, my point is on the track you can easily downshift the SMG twice from a high speed straight to a tight corner. However I'm pretty sure the current SMG can do 2 gear down shifts by quickly hitting the downshift paddle twice. I've only driven a SMG on the track at Watkins Glen which is a 3rd and 4th gear track. 2nd and 5th gear aren't used, at least in my dad's stock 2002 SMG M3. 140mph on the backstretch though, how much fun is that?
Swamp, I can see the need for downshifting on the highway for a quick getaway, however I was talking about track use where you're either full throttle or full brake for 90% of the laps.
Enigma - your description is exactly what I was talking about.
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      03-05-2007, 05:48 PM   #54
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T-bone, why Oprah?
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      03-05-2007, 06:45 PM   #55
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Quote:
Originally Posted by skierman64 View Post
T-bone, my point is on the track you can easily downshift the SMG twice from a high speed straight to a tight corner. However I'm pretty sure the current SMG can do 2 gear down shifts by quickly hitting the downshift paddle twice. I've only driven a SMG on the track at Watkins Glen which is a 3rd and 4th gear track. 2nd and 5th gear aren't used, at least in my dad's stock 2002 SMG M3. 140mph on the backstretch though, how much fun is that?
Swamp, I can see the need for downshifting on the highway for a quick getaway, however I was talking about track use where you're either full throttle or full brake for 90% of the laps.
Enigma - your description is exactly what I was talking about.

I think we are almost splitting hairs but hey this is fun.....

This thread diverged when we started comparing DSG vs. SMG. I used to have an E46 M3 with SMG and now I have a M6 with SMG. I do know the SMG can skip gears and whereas this appears to be a limitation for DSG today.

There is at least one track that I have driven where I need to go from 5th to 3rd and I like to have my car settled before turn-in. SMG allows you to skip to your gear of choice quicker.

While very few people track their cars, I do but skipping gears is even more practical for the street. Hobbling around in 7th gear is not good for acceleration.

If you want to shoot the holes in traffic, you need to get from 7th to 3rd or 4th very quickly.

Why Oprah? Hey I can find my posts......and she is inspirational
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      03-05-2007, 07:05 PM   #56
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I think I misread an earlier post. I thought someone was saying you can't skip gears with the SMG. However no matter which tranny is available on the M3 SMG or DSG I'm sure it will be great. I imagine a DSG will change gears so fast that not being able to skip a gear won't be much of a problem. Regardless, I can't wait.
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