[swamp2]

General: (source)

Originally Posted by swamp2

To me the transmission (M-DCT) is the most interesting and compelling option available with the car and the one that makes it the most unique. Since others have spoken about the car's performance once broken in and most of us have seen plenty of videos, I'll go right to M-DCT, which is the area where much information and discussion is lacking.

M-DCT is fantastic, period. The two basic modes and all of the sub-modes are fantastic as well. Just like the rest of the car (stability control, steering, suspension, throttle) M-DCT is highly adjustable. It defaults to manual mode and a quick flick of the lever to the right places it in automatic mode. I was so excited and nervous when driving off from the dealer I just stuck with automatic mode for a bit. In the lower modes all upshifts occur quite early (at low rpm) and are silky smooth yet still incredibly quick. 7th gear arrives so quickly and with no drama even when puttering around side streets. Rev matches during downshifting are subtle. When increasing the mode number (hence the aggressiveness) the shifts occur at higher and higher rpms. As well the eagerness to downshift (pedal depression required to initiate, specifically) and number of gears that will be taken when quickly stabbing the throttle all nicely ramp up through the modes. In the higher modes 7th->5th (or even 4th) is quick and occurs effortlessly when you just grab even a moderate amount of throttle. Of course it will go even further 7->3 (or whatever) but there is some risk of getting way above the recommended break in rpm limit by doing nothing more than just jamming the gas pedal down. As you might guess I have not used the kick down feature as that would clearly take you well over the suggested rpm limit during break in. If it is anywhere as good as 7->5, I’ll be thrilled.
Moving over to manual mode to use the beautiful full aluminum paddles brings some excitement as well. Like all area of the car the attention to detail is great, the + and – signs are etched into the aluminum and then they are clear anodized. There is a very slight but noticeable delay between the paddle click and the beginning of an upshift. Lucid and others have mentioned a more severe case of this with the VW DSG in the GTI. I suspect this delay is only a very small fraction of what they have reported. Many might say the delay is so short that there is not delay but for sure it is there. Because of this it is actually fairly easy to get past your desired shift point. This is definitely not a real annoyance or detractor but this slight delay is there. This delay actually seems to be longer for upshifts and shorter for downshifts. When driving aggressively the shift lights will absolutely help nail ideal shift points. Manual modes 1-3 are all quite smooth and fast. The real distinctions among them will not be clear until some higher rpm or track work comes around or until instrumented testing can be accomplished. In S4 and S5 you do feel the surge (jerk, snap, jolt, etc.) on upshift that has been discussed extensively here on the forum. Of course the higher rpm of your shift and the further you are in to the throttle the larger the surge is. That being said it is never close to the jerk of SMG (nor that of a well executed shift in a manual). It may be the case that the surge changes smoothly from S1->S5 but as of now it does seem like it is only present in S4 and S5. Double upshifts do catch the in between gear for just a spit second and then continues right on to the selected gear. However, double paddle downshifts seem to skip the middle gear entirely. If they catch the middle gear it is not at all obvious from watching the tach and listening. The double downshifts are definitely more impressive, but who really needs a double upshift when accelerating with any vigor whatsoever? In this way the M-DCT during upshfiting is very much like a true sequential. At this point my favorite mode is probably S3, just a perfect combination of speed, feel and rev matching. Take off from a start, wind her up to the recommended 5500 rpm limit (grab the paddle at about 5000) and boom, you are in second in an instant, fast but smooth, the revs build really fast right back to 5000 rpm again, grab the paddle again and you are in 3rd, again in an instant. Like Chris from Autocar said, “it’s like a dog box… like driving a racing car”. Lather, rinse, repeat, it is almost brainless yet is still quite satisfying at the same time. I can't wait for the M-DCT experience at 8000+ rpm and at those rpms in the twisties. Launch control will certainly be a huge blast as well. I just need to keep up the proper restraint until the magic 1st service.

+ and -: (source)

Originally Posted by swamp2

Advantages of DCT(not in any particular order, except the first):

• DCT is THE single option that will make the car have better performance, straights and twisties (it is very close to a 6MT with 440 hp and 320 ft lb torque)
• DCT is customizeable through software (perhaps both BMW and other)
• Manual modes via paddles and stick and automatic mode for traffic jams, comfort or inexperienced drivers
• DCT allows one to focus on more cerebral and challenging aspects of performance driving
• DCT provides better fuel economy
• Launch control should be fun, fast and consistent
• No "money shifts" with DCT
• DCT is race technology for the road and BMW claims it is designed for race level "abuse"
• Rev matched downshifts
• The inherently smooth shifts with DCT may provide less shock and better wear of some transmission components
• Clutch pedals are so 1950s

Advantages of MT:

• Simplicity and perhaps reliability
• False pride in your rowing abilities enabled by MT

Kick down feature: (source)

Originally Posted by swamp2

Small update: Kick down.

Sorry I have not yet posted any LC videos. I have not actually even used it yet. Getting to redline these days and playing more with the DSC system settings, fun, fun. What I did finally give a try is the kick down feature. While in any manual (S) mode you can obtain the best gear for maximum acceleration whether that is 1 shift down or 5 nearly instantly with this feature. Simply floor the gas hold down the left paddle and BOOM in as fast as a single shift (maybe "only" as fast as the sum of two nearly instant down shifts) you are instantly in the best gear and really accelerating. The advantages over a MT here are fairly obvious: no deciding which gear, no complex movements to get to the right gear, no chance of over-rev, no chance of grinding, perfect throttle control and did I mention it is FAST. This is not all that useful when driving aggressively to begin with but is very useful when cruising at fairly low rpm in a high gear and (for one reason or another ) you want instant and max acceleration. Mostly played with it using 7-4 shifts begining at about 70-80 mph.

Fun, fun, fun.

Launch control: (source)

Originally Posted by swamp2

When using LC all shifts are fully automatic, despite it being in S6 mode (a manual mode). Shifts are right at redline. This works properly ONLY if you keep the pedal glued to the floor.

I finally used it myself (obviously). It is a bit scary and I am a bit embarrassed that it is not quite as easy as it seems. However it is all me and not the car. The first time I accelerated a bit slower than expected and left a huge could of smoke. I think you really want to use MDM when using LC to limit wheel spin. It also appeared it was not going to do the 1-2 shift so I grabbed second with the paddle. I promptly got into the rev limiter and power was cut. Tried it again by choosing M mode (which includes MDM for DSC in my settings). Things were a bit better but I still managed to hit the rev limiter as I think I did not keep the pedal 100% depressed and then got back on it (pretty sure it reverted to full manual mode if the pedal is not left 100% depressed.) Clearly I need to get to a location where I will not be arrested and thrown in jail for more experimentation, more fun and a video.

Feeling like such a rookie....

If you use LC use MDM and DO NOT LIFT THE GAS.

Speed of shifts and rev matching (blips): (source)

Originally Posted by swamp2

Shifts are always fast, they are slightly faster when the TCU (not an official BMW term but loosely the "transmission control unit") properly guesses the next gear but only from the delay perspective, not the shifts themselves. There is just a slight delay when it doesn't (can't) guess correctly. For example at low throttle, with no acceleration nor braking and in a high gear (not 7th) there are very little clues for the TCU to properly guess the next gear. If you nail the throttle it perfectly pre-selects a lower gear, closer to redline it pre-selects the higher gear. Under these conditions the delay is almost imperceptible. Again, much like most of my minute "criticisms" of M-DCT I have noticed this but 95% of folks won't it is very minor and you have to pay close attention to the initiation of the tach movement compared to the completion of the lever or paddle click. Now with this small diversion on the speed of shifts on to the much more fun part of your question...

1-2 chirps pretty good at high throttle in S5 and S6, when shifting near redline, LC or not. I too would really like to know how many gears will chirp using S6&LC with MDM off (automatically shifting right at redline under WOT). The M6 with SMG III chirps just a tiny bit into 5th, but clearly the M3 won't with 90 or so less ponies! It is beyond illegal to test this on the street hence I have not done it, nor do I have it on video. Hopefully soon.

Some more experience with rev matching ("blips") on downshifts:

Almost no throttle blips occur in S1-S3 at low to intermediate throttle. I have not checked it at very high throttle but I think the results will be the same. The lower modes S1 and S2 purposefully delay, smooth and "slur" the downshifts a bit. These are the only conditions and modes under which shifts are slower than incredibly fast. They are still fast and very smooth but produce no blip and they take just a hair longer. As well you feel a bit more compression braking during the clutch swap. In S4-S6 the intensity of the blip and propensity for it to happen at lower and lower rpm smoothly increases through the modes. S4 is about perfect for slightly aggressive driving. Nice blips, still super smooth, definitely easy on the syncros and the nice aural pleasure as well. My initial impression is that the S5 and S6 blips may be too large and less smooth for mild to moderate driving. Much like other aspects of the tranny though the faster you go and the harder you push it the better it gets. So I very well expect S5 and S6 to be great for very aggressive driving and track work. My comrade footie would surely conclude that any roughness in the blips means they are positively too large and too aggressive and are present only for the aural effect (or some other false feeling of speed, poseur effect, etc.). As well I'm sure he would say there is absolutely no need for these modes to even be present. Even if this were true, which I highly doubt, it may be worth it solely for the sounds as they are truly heavenly.

With my past comments about the differences between the up and downshifts in the D (auto) modes and the wealth of comments about the surge, I feel I finally really know the tranny for most conditions except the very aggressive and track type work which I really hope to get to soon.

As I always say M-DCT gets a 9.5/10. Most will never notice the tiny, almost insignificant "criticisms" I have found in the unit. Like the rest of the car the more you push the better it gets.

M-DCT FTW!

P.S. Sorry to thread jack (just a bit) but Jasons post quickly went down the M-DCT route.

Low speed coming to a stop: (source)

Originally Posted by swamp2

Nope don't get that. I do very rarely get a very slight clunk from the clutch and an accompanying miniscule jerk when just about stopped as the clutch timing is just a hair off. As I have stated before this is VERY MINOR, very rare and barely noticable. Such small imperfections are noticeable when the tranny is so close to perfect. If you think these tiny imperfections are a huge deal you must ask yourself how many times would you have a similar tiny goof with a MT?

DCT "lag": (source)

Originally Posted by swamp2

The misinformation continues... BTW for those that do not know I am a M-DCT owner/driver and am well past my first service.

There is a feeling of sluggishness you will notice when you first start to drive a M-DCT M3. It will be there in the Normal and Sport throttle settings. I have not used Sport Plus much but expect it to be there as well. All I think this is is a fairly slow de-clutch when starting out from a dead stop UNDER LOW THROTTLE conditions. The transmission mode S or D nor any of the numbered Drivelogic settings have very little to do with this. The way to get this to change is to simply give it more throttle. Problem fixed. I know I for one have been gentle on the car, breaking it in conservatively and according to BMW guidelines. As well with a new tranny and something as different as M-DCT is, most proceed a bit slowly. These issues certainly contribute to the observations of "lag".

Let me appeal to logic. How can the car, when capable of 0-60 in 4.1 s and 0-100 in 9.4 s be "slow" or "sluggish off the line? IT ISN'T, period.

Although I have not used LC yet, I have gone for aggressive take offs in S6 with MDM engaged (the aggressive DSC setting that allows limited wheel slip but still has DSC on) and all I can say it WOW. You get to redline so fast in first, limited wheelspin and BAM you are getting the shift lights to hit 2nd. There is no lag nor disappointment whatsoever.

As far as the comparisons with the E46 M3: How many folks who came from the E36 M3 (maybe even modded) to the E46 M3 felt the E36 M3 was faster, or at least more astutely noticed that it only FELT faster. It did FEEL faster but it clearly wasn't. Sorry guys this is simply refinement. Get used to it. Same thing here comparing E46 and E92.

Footie: We have already been through the issue (ad infinitum) of whether or not S4,S5 and S6 and the jerk they provide on shift improves acceleration. All you have to do is notice the wheel spin/chirps on shifts due to the jerk and you can conclude immediately and clearly that these modes and the jerk is faster then without them. Sure maybe not .5 s faster to 60 or 100 but it will be noticeable and measureable. S3 and lower Drivelogic modes just do not provide jerk nor chirp on shift at large throttle. Bruce A. agreed with this on a technical and experiential basis as well. YOU ARE WRONG HERE but just won't admit it. JERK = CHIRP = BETTER acceleration.

So in conclusion, you will notice this "lag" but it disappears the more throttle you use. Add in all the other benefits of M-DCT and its perfect and blazingly fast shifts and this really just becomes something you will get used to. Do test drive a M-DCT if you are concerned. Test drive it ONLY after proper break in and don't hesitate to give it some juice.

I am thrilled with this transmission.

M3 Owners Manual with M-DCT: (source)

Originally Posted by swamp2

Not available yet on the OC website but my dealer had this and sent it along. Enjoy.

Download link: M3 Owners Manual (M-DCT).pdf

Lengthy M-DCT Technical Press Release (Source)