First driving reviews of M3 M-DCT / M-DKG transmission!

[swamp2]

Originally Posted by mofomat

What utter, utter, nonsense. Go away quickly, and close the door behind you.

[SMSgt B]

thanks for posting the reviews. Now I am off the hook ...

[DonM3]

Swamp,

I think it was Uli_HH who broke the news and not Just Me.

[rvacha]

Originally Posted by southlight

OK, here's the first part:

Yet another valuable service from members of the 6MT Club!

[southlight]

Updated the third persons impressions. One still to come...


Best regards, south

[goldminer]

Originally Posted by footie

I am less impressed by this review, especially the jerk during upshifts. The whole reason of dual clutch is to be seamless in the changes, not noticeable and jerky like they were with SMG. Unless my understand of what the guy that wrote this is different I doubt I will like this that much.

I would also like to see performance figures for each of the different modes (Auto and Manual) to see if they effect the acceleration. If so then in my opinion BMW have f--ked things up BIG TIME.

I read the reviews and, although the English was bad, I took it to be more of a surge, not a jerk. Also that it was only there in the more agressive shift modes (S4 to S6). It did say that D1 and D2 were very smooth.

"D1 and D2 are like the Audi ad claim, shifting almost imperceptible "

So you can have it agressive or you can have it smooth at the flick of a switch. Where did you get that it was a jerking movement?

[T Bone]

Originally Posted by footie

I am less impressed by this review, especially the jerk during upshifts. The whole reason of dual clutch is to be seamless in the changes, not noticeable and jerky like they were with SMG. Unless my understand of what the guy that wrote this is different I doubt I will like this that much.

I would also like to see performance figures for each of the different modes (Auto and Manual) to see if they effect the acceleration. If so then in my opinion BMW have f--ked things up BIG TIME.

Wow... Do you really believe what you write? The jerk on upshifts is a natural thing. When you have an engine at 8400 rpm and upshift, the next gear will bring down the RPMs by 1000-2000 rpms. This difference in RPMs must be absorbed by the transmission speeding up and the engine slowing down....

This translates into tire chirp on upshifts at redline.

If a meat computer can shift a manual transmission as quickly as MDCT, then it would also get the same chirp. But we know the mean computer is slow.

I will tell all of you guys this.... With SMG2, the E46 M3 didn't have enough power to really showcase the upshift tire chirp phenoma.... The M5 / M6's V10 with SMG3 does and it is a GLORIOUS sensation and not an annoyance.

With the E9x M3, it will have enough power to make this chirp....

Don't fear it, it is like a good thing.

Originally Posted by swamp2

DCT WILL be worth about 20 hp and 20 ft lb (equivalently). The larger gear ratios AND shorter shift times will do this, period. If you do not disagree that the car will be measureably faster how can you disagree that there is not a significant and equivalent hp/tq gain? You've got this one wrong.

As far as the perception of gear changes it sounds like the system offers a full range of performance, barely noticeable changes in some modes, and noticeable not not nearly as noticeable as SMG in other modes. This does not mean much as all in terms of the performance advantages. All it really means is that I was a bit wrong about the particular design direction they took and whether or not super fast could be mixed with super smooth. That being said I always agreed with enigma that there is a certain amount of engine, flywheel and drivetrain inertia and that has to go somewhere.

The Cartest2000 simulations don't support significantly faster acceleration for the MDCT.....the reason the MDCT is faster is quicker shift times and not gear.

That is what the data says....let's see it on video

[footie]

Got a bit of flak from my comments which was to be expected.

Maybe I didn't make myself clear with my comment 'F--king it up BIG TIME', this comment was based on the belief that you only got the fastest acceleration when in the S6 mode which really would defeat the purpose of using a dual clutch transmission. If this isn't the case and all of the differing modes offer equally as quick of acceleration than I stand corrected.

If this is not the case and only S6 with it's jerk/surge gives the desired results then I stand by my opinion. The SMG was one of the worst gearboxes I ever tested and the thought of BMW choosing to offer something similar just makes me so disappointed.

Remember unlike most of you here I have a lot more experience of this type of transmission than most.

T-Bone, your opinions that the jerk is a natural thing is total and utter BS, I know someone who has sampled the Veyron and his comments and disbelief was how something with so much power and acceleration could be so totally smooth between gears.

I will hold judgement on the transmission until I get to sample it but I hope before that happens that some magazine does the kind of review which tests the acceleration between the different modes to see if the jerk/surge is only added to give the impression of speed.

In my opinion the jury is still out.

[T Bone]

Originally Posted by footie

T-Bone, your opinions that the jerk is a natural thing is total and utter BS, I know someone who has sampled the Veyron and his comments and disbelief was how something with so much power and acceleration could be so totally smooth between gears.

In my opinion the jury is still out.

Usually a person needs to have a basic grasp of physics and math to render another's opinion BS.

Have you ever heard of power shifting on manual trannies? Same thing as the upshift chirp.

Stick to your 6MT as this seems to be the only thing you seem to understand.

[WCH]

Sounds great. Can't wait to experience it myself.

[Just_me]

How can someone be against jerkiness in manual mode in the fastest setting (S6)?, That is great thing and racing inspired. Dont want it another way.

What also positive is that in automatic mode the gearchanges are smoother than SMG becuase this have been the weakest part with SMG. This is what car reviews have been dissing. So this is good news.

[southlight]

Originally Posted by goldminer

I read the reviews and, although the English was bad

Added the last part to my post. Hope it's somewhat comprehensible.


Best regards, south

[ersin]

It sounds like the M-DCT will be everything we hoped it would, and then some. We still need to wait for "real" people to starting driving it and report back. But if it is that good I might just consider spending the $2700 for it. Maybe.

[ersin]

And thanks for the translation south!

[footie]

Originally Posted by T Bone

Usually a person needs to have a basic grasp of physics and math to render another's opinion BS.

Have you ever heard of power shifting on manual trannies? Same thing as the upshift chirp.

Stick to your 6MT as this seems to be the only thing you seem to understand.

Agreed, I don't have the same grasp of some of the technical stuff that some of you might have, I only know how to drive extremely quickly.

T-Bone, can I ask, how much experience do you have with Dual Clutch Transmissions? Somehow I don't think you have quite grasped what makes them so different to your disastrous SMG. If BMW have designed in the jerk/surge and it doesn't effect the acceleration then all is well, but if you only gain the maximum attack with it then a lot of people will be turned off, myself included.

[jtown]

Originally Posted by T Bone

Usually a person needs to have a basic grasp of physics and math to render another's opinion BS.

Have you ever heard of power shifting on manual trannies? Same thing as the upshift chirp.

Stick to your 6MT as this seems to be the only thing you seem to understand.

pwned.

[T Bone]

Originally Posted by footie

Agreed, I don't have the same grasp of some of the technical stuff that some of you might have, I only know how to drive extremely quickly.

T-Bone, can I ask, how much experience do you have with Dual Clutch Transmissions? Somehow I don't think you have quite grasped what makes them so different to your disastrous SMG. If BMW have designed in the jerk/surge and it doesn't effect the acceleration then all is well, but if you only gain the maximum attack with it then a lot of people will be turned off, myself included.

Yes Footie, you are a legend in your own mind

BMW could have easily designed smoothness into it since it is throttle-by-wire, but they chose to let nature happen. They will leave the girly shifting to DSG and women who put on their lipstick in the mirror.

The snap / chirp is a desirable feeling....you really need to experience it before you can render an opinion here.

If you do insist on putting on your makeup Footie, lift when you upshift and the tranny computer will give you a DSG type of upshift. WOT makes the tranny shift quickly as possible for the snap / chirp...

You will like it.

[footie]

T-Bone,

I have already said I will only be able to make a proper opinion on the system when I sample it for myself. After reading the third and fourth review that South kindly added I can see lots to like about the gear box.

I think by the sound of the reviews that the people which got to sample the car from the passenger seat all either own or owned SMG cars and it looked like they could only relate to quick shifts if there was a jerk/surge with the change. I hope that DCT is just as quick in acceleration in the lesser modes as there is no reason for them not to be.

Also remember that I had DSG and didn't care for it much but the reasons for this centred more so with living with the system and finding that the auto modes were the best for me. Maybe DCT has improved on these failings, maybe not but I do want to try it for myself to see if it would be something to think of in the future.

[T Bone]

Originally Posted by footie

T-Bone,

I have already said I will only be able to make a proper opinion on the system when I sample it for myself. After reading the third and fourth review that South kindly added I can see lots to like about the gear box.

I think by the sound of the reviews that the people which got to sample the car from the passenger seat all either own or owned SMG cars and it looked like they could only relate to quick shifts if there was a jerk/surge with the change. I hope that DCT is just as quick in acceleration in the lesser modes as there is no reason for them not to be.

Also remember that I had DSG and didn't care for it much but the reasons for this centred more so with living with the system and finding that the auto modes were the best for me. Maybe DCT has improved on these failings, maybe not but I do want to try it for myself to see if it would be something to think of in the future.

You see footie, if you had posted above instead of "BMW F--king it up BIG TIME", none of us would have ridden you like the town whore.

[apw2607]

Well after reading the english translations (many thanks), and the discussion from the various knowledgeable experts on the subject ...

I'm going to try and cancel my M-DCT order which is arriving in 2 1/2 weeks at my dealer ... Its a nice space grey will all options. Instead I think I will buy a nice Audi S5.




NOT !!!

[hakaida442]

I was under the impression by the bmw dct video (especially the part that shows shifting during a turn) that shifts would be fast but not jerky which would lead to better and smoother performance. I guess I'll have to wait for more real life reviews and a test drive it in various modes. I want auto tranny smoothness in everyday traffic, but want more performance (faster shifts) without shifts disrupting the chassis too.

[footie]

Originally Posted by T Bone

You see footie, if you had posted above instead of "BMW F--king it up BIG TIME", none of us would have ridden you like the town whore.

T-Bone,

If BMW offers equally as quick acceleration from the lesser modes than no harm done, but if not then it will be a major F--k up in my opinion.

P.S.
On the most part I have been a great supporter of the technology, regardless if I personally wouldn't pick it for myself based on my experience with DSG. Maybe DCT will change that opinion which would be a bigger shock to me than any of you.