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Originally Posted by NoTempoLimitN54
OK, so if the conventional torque converter 6 speed automatic is superior in performance to the 6 speed manual, why does BMW bother with the DCT? Why is the conventional 6 Speed Auto not available in the 1 Series M Coupe (manual only), the 335is (manual/DCT) or the E90/92/93 M3 (manual/DCT)?
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From what I've gathered from this forum, the ZF 6 speed steptronic shifts within 400ms, the DCT shifts within 200ms. So, because racecar.
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"A few members who track their cars..." you're talking about the dragstrip right? Because on the race track, being faster off the line is inconsequential because of the flying start (unless you're doing an old-school Formula 1 grid start).
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I am talking about the dragstrip. I have no idea if a manual would best an a/t e90 on the racetrack, all else being equal, but people in this forum claim the a/t and the dct will be faster.
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Also, if you are really tracking a 335i, the AT makes your thermal problems worse because the AT needs to reject it's heat into the engine's cooling system (using a oil/water heat exchanger). So AT 335i will overheat sooner on the racetrack. Just search for the "335i Limp Mode Party" thread for more details on this.
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Yeah, that's why I'd prefer a DCT for the racetrack.
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6MT 335i with the stock oil cooler and using less than 50% coolant:water ratio and a "water wetter" such as Redline, Motul, etc. can usually avoid limp mode tracking on all but the hottest days. 6AT 335i needs supporting mods such as larger oil cooler and perhaps the PPK V2 auxiliary radiator to avoid overheating on the track.
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My a/t with stage 2 ppk(which, for me, included a water cooler, oil cooler, and better fan) is supposedly much better at the track now. Someday I'd like to find out, but I have no time right now. Again, I'd prefer a DCT.
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BTW, I'd like to see those "majority of magazine tests", please post sources. The last time this subject came up on here, my position was confirmed, although admittedly the the 6AT's 0-60 advantage is small (but so is the DCT's advantage on the 6MT).
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I don't keep a categorized compilation of reviews and comparos, but I am sure you could find plenty yourself.