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DCT vs Non DCT
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01-24-2012, 06:13 PM | #1 |
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DCT vs Non DCT
Can someone explain to me the advantages of a DCT in the 335is over the standard transmission in the 335i?
What exactly does it do? |
01-24-2012, 06:15 PM | #2 |
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Shifts faster than pretty much anyone on the planet can in a manual.
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01-24-2012, 06:24 PM | #5 |
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Less slippage while accelerating. Almost nonexistent gear shift change.
Probably more expensive just to maintain; S-Tronic or DSG (VW/Audi) require 350-400$ 40000 miles maintenance). Yet the new ZF 8-sp. makes it less appealing. |
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01-24-2012, 06:27 PM | #6 |
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launch control
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01-24-2012, 06:27 PM | #7 |
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01-24-2012, 06:34 PM | #8 |
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Depending on the source, regular ZF shift in 100-200ms. A blink of eye is 300ms. Best DCT I heard (under reserve) of is 40-60ms. Don't know abut BMW's DCT.
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01-24-2012, 06:40 PM | #10 |
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01-24-2012, 06:41 PM | #11 | |
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Quote:
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01-24-2012, 06:45 PM | #12 | |
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Quote:
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01-24-2012, 06:53 PM | #13 |
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I remember some magazine did comparison on E46 6-speed M3 vs SMG M3 and out of 10 launches by pro driver only 1 matched SMG, other 9 launches were slower and not consistent. SMG all 10 launches gave pretty much the same time.
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01-24-2012, 06:56 PM | #14 |
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I drove a new 650i with the ZF 8 speed last year, pretty much equals DCT in shift times.
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01-24-2012, 07:02 PM | #15 |
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Bear in mind that in a most cars, 335is included, you won't see that big of a improvement of 0-60 times between Manual and DCT (I'm guessing on the TT-RS launch control is magical, or other factors such as US vs Euro spec). |
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01-24-2012, 08:03 PM | #17 |
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Its got real clutches & real gears...think of it as a 7MT driven by a robot. One reason its quick is not just the pure shift time but the fact that you don't need to lift the throttle between shifts so you are never out of the power.
When running against a MT you can see the drop back on every shift when they lift. If they don't lift on the shifts you might see the car grenade as it will happen sooner or later with out a properly prepared gear box that is not suitable for the street.
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01-24-2012, 08:08 PM | #18 |
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The 335is DCT should not even be compared to a regular automatic transmission of the 335i. They have absolutely no relation to one another.
DCT is more in relation to Manual Transmission but it is automated and has two clutches |
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01-24-2012, 08:09 PM | #19 |
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How are the shifts, Bear, are they smooth during normal driving as well as under throttle?
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01-24-2012, 08:14 PM | #20 |
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i heard that the 7speed is converting more horsepower to the wheel than the 6auto
for example comparing a stock dyno runs between the two cars both of them has n54 with 306 engine horsepower the 7 speed dct will give you 250 whp the 6 auto will give you 240 or 230 these are not real dyno numbers but i am trying to explain that the dct will give you more power in the wheel than the 6 speed auto |
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01-24-2012, 08:25 PM | #21 |
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I wish I understood the mechanics better. The a/t outputs more torque than the manual when the PPK is installed to a 335.
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01-24-2012, 09:34 PM | #22 |
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Has anyone driven the ZF 8speed against any dual clutch back to back?
For me, more so than just shift speed, what I loved about my old S-tronic was the lack of 'slushy' feeling by not having a torque converter. Does the ZF solve this problem too? I have the 6 speed GM box in my 325...while I can't say it's terrible, I can say it is the worst part of my car! I would have got MT, but that is not possible in the Taiwan market. Some days it just makes me go....grrrrr! It shifts reasonably quickly most of the time, but does not have the immediacy that the direct connection of a MT and dual-clutch box offers. So that's what I really want to know...how does the ZF 8 speed feel, not just how quickly it shifts. |
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