BMW M3 Double clutch transmission testing

[fordgt84]

the good ppl from m5board have been busy testing out bmw's new double clutch gearbox... the vids are a bit long, but if you've got time they're quite interesting, enjoy :thumbup:

part 1
MBOARD.com test of BMW M3 E92 DKG DCT Double Clutch 1/2 - YouTube

part2
m3e90board.com test of BMW M3 E92 DKG DCT Double Clutch 2/2 - YouTube

hope it's not a stan again :bored:

[5vz-fe]

The VW DSG seems to be a faster shifter even tho both are dual clutch system.

[styla21]

The VW DSG seems to be a faster shifter even tho both are dual clutch system.
Do you know what the official shift times are?

[5vz-fe]

^Nope...sorry. My comment is only based on video observation.

[5vz-fe]

R32 DSG Launch Control - YouTube

[styla21]

Ok, so I did some research and i'm impressed! :-)

If we assume the time between shifts is calculated as
the time that the wheels are unpowered"
1.The VW system - "DSG" takes about 8 milliseconds to upshift.
2.The BMW system - "DCT" (Dual Clutch Transmission) - is stated as less than a tenth of a second.

So if we assume a maximum of 2 milliseconds difference, it is practically impossible for us to differentiate between the two. I wonder why the F1 teams aren't running this setup? :?:

They only drawbacks for using DCT's in production cars, apparently, is a higher production cost, and added weight (as a rough guide - 75kg, as opposed to 45kg for single clutch setup).
Also, if you want to select a gear that the system was not anticipating, it is very laggy (400ms) until that gear is engaged.

[5vz-fe]

I think Dual Clutch will be the way to go if you do not enjoy shifting it yourself but desire the directness and performance. In full automatic, it's quite impressively smooth.

[yg60m]

Thank you, very interesting videos :thumbup:

[04RCSTI]

Gaahhhhh Im going to be kicking myself for not buying that M3 pretty soon...

[styla21]

Gaahhhhh Im going to be kicking myself for not buying that M3 pretty soon...
What did you buy instead? An STI?

[Svensson]

Ok, so I did some research and i'm impressed! :-)

If we assume the time between shifts is calculated as
the time that the wheels are unpowered"
1.The VW system - "DSG" takes about 8 milliseconds to upshift.
2.The BMW system - "DCT" (Dual Clutch Transmission) - is stated as less than a tenth of a second.

So if we assume a maximum of 2 milliseconds difference, it is practically impossible for us to differentiate between the two

A tenth of a second is still 100 milliseconds, so according to your data the DCT shifts 90 ms slower than DSG.

[styla21]

A tenth of a second is still 100 milliseconds, so according to your data the DCT shifts 90 ms slower than DSG.

Thanks Svensson. No idea how I mis-calculated that one!..:blink:

[unwilling]

Doesn't Ferrari's gearbox in the Scuderia take 60 milliseconds to shift?

[turpija]

.. I wonder why the F1 teams aren't running this setup? :?:



the McLaren announced they are working on a double clutch gearbox few years ago, I don't remember the exact number but I think they said that car would be on full throtle for 2 more seconds per lap then the standard sequential gbox which is a lot in F1, but I'm guessing the FIA pull'd the plug on that also, just like when Honda tryed to get the CVT gbox few years before that.

[JoeHahn]

Dual Clutch gearboxes are banned in F1 - its classed as having 2 transmissions.

[04RCSTI]

What did you buy instead? An STI?

Well, I bought an 04 STI instead of getting an E46 M3 back in the day and now I have an 06 STI and I was very close to getting an E92 M3. I plan to track the car a lot and not only do I feel the STI is more capable, but I would hate to see big chunks of R-comp streaking up the hood of the M3.

Not that I need them, but I was just thinking the other day how awesome it would be to have paddles on the track..This video definitely didn't make me feel better about having to heel and toe like a caveman.

I love shifting a manual on the track too, but I find DCT very attractive.

I'm going to go drive one of these paddle M3's when I get back to FL in a few weeks... although i dont think they are available for TD at dealerships until June...