M3, meet DSG: BMW M3 gets 7-speed double clutch 'box
click above image to view more pics of the 2008 BMW M3
BMW dealers in Europe have received the officially official specs of the new M3 only to discover that the car with be offered with a new seven-speed double-clutch gearbox, much like the DSG trannies used by VW/Audi. Dubbed the M DCT (M Dual Clutch Transmission), the cog swapper is expected to speed up shifts and shave a couple of tenths off the car's 0-60 time, which should put it squarely in the 4.5-second range, if not quicker. The system, developed and produced by Getrag, will likely be better received than BMW's maligned SMG trannies and eventually replace those systems in the 3-Series and 5-Series lineups. The M DCT will be controlled with the requisite paddle shifters on the steering wheel and an odd little joystick control on the center console like the one in the M5 and M6.
[Source: Autocar]
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Reader Comments (Page 1 of 1)
borganswerman 1:55PM (3/31/2008)
The M DCT is from Getrag, as is the 7-speed SMG in the M5 and M6. It has a 4.8:1 1st, 1.0:1 7th, so the ratio spacing is very close, about the same as the SMG and the 6 speed manual. Seven may seem like overkill but if it is as good as the VW DSG (it should be) that tight ratio spacing will feel seemless, not busy. T'is the beauty of DCT.
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bgdc 1:29PM (5/31/2007)
Excellent. The DSG in my fiancee's A3 is a fun alternative to a real manual and when I trade in my 6 speed Cooper S for a 335i in 09/10, hopefully the DSG will be available. We can both drive stick but it's much easier for her to use the DSG.
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Zain 5:20AM (6/01/2007)
bgdc: Wow! You just stole my plans! R56 MCS over here! :)
bgdc 11:12AM (6/01/2007)
R56 MCS is what I have too. It's my last hurrah with a small car before we have a family. Once she's 5 months pregnant I'll order my next bimmer for Euro Delivery. God willing that's still a ways off...
srivendel 1:40PM (5/31/2007)
I know this is somewhat off-topic, but I still can't understand why BMW chose milky red for its press photo car. The "concept" version, with its BBS-style wheels and alloy paint color, looked amazing, but the car in these photos looks like a German tuner test mule.
One of the hallmarks of a pure design is that it looks great in almost any paint color. This M3, while handsome, is not BMW's finest styling effort. It is a very paint-sensitive design.
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Rocket Punch 1:45PM (5/31/2007)
Clap Clap, BMW finally saw the light. The SMG was a good try for them, but they can never really make it work well. DSG is clearly the way to go, but don't get me wrong, no semi-auto can replace the fun of full manual. However, If that actually makes the car faster, I am all for it. It just won't be in my CSR260 (if sometime in the future I can afford one...)
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The Other Bob 2:02PM (5/31/2007)
Getrag huh?
Expect this to show up in other car makes.
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shimman 2:10PM (5/31/2007)
nice, but why stop at 7speed? when they could have had a 8 speed box
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thesawzall 2:33PM (5/31/2007)
I think it's most economical when they pair the gears up. You have to have reverse, so an odd number of forward gears it is.
Is it Nick Heidfeld/Robert Kubica approved?
The Other Bob 2:47PM (5/31/2007)
Why stop at 8? They could have 9, or 10 or 12.
You have got to stop somewhere.
shimman 3:01PM (5/31/2007)
just because is-fs or whatever will have a 8 speed box which is currenly on ls460
paul34 3:06PM (5/31/2007)
Gear wars are silly because they're really nothing more than "my dad can beat up your dad" sort of things.
Add more gears, and you'll make the existing gear ratios closer and closer together before you end up to where you're shifting (well, the computer I guess) so often that it is ridiculous.
6 or 7 well-ratioed speed is ALL any high performance vehicle needs... IMHO.
Plus, that's not even mentioning the extra weight, space, etc. trannies will end up taking with the additional gears. If you want a lot of "gears," get a CVT! (although I don't think I'd wish that on anyone heh).
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Fooman 3:15PM (5/31/2007)
The SMG is odd, Foo girl has a z4 with a SMG, and it is either a better manual or a horrible automatic. BMW exec have aid the worst thing they ever did was but a full auto mode on the SMG's. I think that this is true when ever anyone else drives the car they try it as an automatic, but the hate it as you have to get off the gas on a shift like a manual. It is different love it or hate it, I personally like it a little better, gives you all the benifits of a manual without having to worry about the clutch, which is nice in socal traffic.
I have not had a chance to try the DSG found in the GTI as of yet, but I am curious.
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Mike 3:18PM (5/31/2007)
More gears means better efficiency not necessarily more power.
Shove your 8-speed...
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SOhp101 3:23PM (5/31/2007)
Hurray for DSG! A much better alternative to manual. SMG is just too jerky for what it's worth.
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Cypher09 3:38PM (5/31/2007)
Hopefully BMW sends ones equipped with launch control to the U.S.
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JC3 9:32PM (5/31/2007)
this 3 series coupe design kinda reminds me of a Pontiac.
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mk 12:32AM (6/01/2007)
actually a transmission doesn't do anything for power, besides maybe sapping a little.
The power is the engine's department. the gear multiplier, or reduction just manages how thousands of revolutions per minute get translated to tire rotations per mile, with appropriate mechanical advantage.
7 speeds isn't bad. But actually, with a broad torque curve that such a V8 as the M's should *NEED* fewer gears, not more. a peaky-er, steeper torque curve would need more gears to keep the mechanical advantage in a narrow range of engine RPMS, where the power is.
A 5-speed DSG would probably work fine, but a little bit of cruising RPM consideration, and a lot of marketing got put into play, and 7 it is. Hard to sell a V8 M3 with fewer gears than the competition, when most people think mo' gears = mo' bettah.
Personally, I think the styling of the e90 is blander than it's predecessors, and this M3 can't shake that, AND the M-specific bumper covers, and the flat hood "dome" are too over-styled to try and inject some visual life into the design. Visual overcompensation.
The odd red paint doesn't help. It almost looks like one of the new matte paint jobs, which also don't impress me.
Put that V8 and rear-drive DSG into a new M-coupe with completely re-styled rear bumper, and completely new front end styling, and a less odd dash... and then you might have something.
I still like porsche designs better, though. Maybe a coach-builder will use this admittedly interesting BMW drivetrain into a truly special automobile design.
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MikeW 6:34PM (6/03/2007)
The transmission[gearing] very much determines power.
Imagine a bugatti veyron with a two speed planetary(something like a powerglide)
Ohhh 1st gear goes to 100mph, then high (direct drive) goes to 250mph. Slow.
From the bugatti website(veyron-engineering-transmission), 1st goes to ~100kph, 2nd 150, 3rd 200, 4th 250, 5th 300, 6th 350, 7th 400. Fast.
BMW gave the M3 a bigger engine, yet the top gear is even shorter than the outgoing M3. Hopefully that will change before any ship.
http://www.bmwusa.com/NR/rdonlyres/E2DF8A41-714F-4846-9066-E558310AB8D8/0/070405_The_new_BMW_M3.pdf
If the 7 speed is just a conversion of the SMG, then because of the taller overdrive ratio (.83 vs .87) then it would be more appropriate for the 3.846 axle ratio vs the 3.62.
http://www.bmwusa.com/NR/rdonlyres/234D7BEF-FB3E-47D2-ACD4-679765930145/0/M5_M6_brochure_new.pdf
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