N55 DCT vs 6spd comparison?

[RPM90]

So, have there been any accel comparisons between the DCT and the manual yet?

Also, has anyone had any accel numbers with a manual N55 so that we can compare the N54 manual to the N55?
I believe the N55 manual has the same trans/gear ratios as the N54, so that would be a truer comparison in regards to how well the N55 produces power.

I haven't seen any media outlets do this comparison. All of them have been testing the DCT version.
I know most of us are curious as to how the twin scroll compares to the twin turbo, and to me that is best judged between the manual versions, cause we know how quick the DCT is.

People have speculated that the N54 was under rated, and that the N55 claims the same HP/lb ft numbers only because that's "all" it produces, implying the N54 puts out greater power.
A test between the two would shed light on that.

[Alext]

Dynos show that the N55 puts out the same power as the N54 so it is also underrated. There is one on N54tech.

[RPM90]

Good info.
Thanks guys.

I don't see any owners/posters posting about how the N55 manual feels.
I'm interested to see how the manual compares to the N54.

I'll be going to some BMW dealers next weekend to get feel for myself.
It's surprising that BMW rates the manual only .1 sec slower, cause the DCT is one fast trans. I was expecting the DCT to be more than .2+ sec faster, considering the DCT has 1 more gear by which to do an overdrive. BMW could have made 1-5 shorter to get even faster accel times and still used 6th for a decent highway drive gear and 7th for tall overdrive for MPG.

Does anyone have a link to the gear ratios for the DCT and the manual?
I'll check bmwusa.com they usually list them.

[KingOfJericho]

I thought I saw a thread where one of the tuners dynoed both cars and found that the N54 had about 10 more horsies but roughly the same torque.

[bradleyland]

I've driven both a 2010 and 2011 135i on test drives (as recent as a few months ago) and they feel remarkably similar to me. They dyno comparisons would tend to support that feeling:

http://n54tech.com/forums/showthread.php?t=7775

The N55 gives up a little in the 3-4k range, but holds on marginally better past 5.5k. Honestly, I think you'd be hard pressed to find any significant difference between the two in stock form.

[RPM90]

Originally Posted by maxnix

There is a a BMW published figure of 5 and 5.1 for 0 - 60 mph in the Series 1 135i 2011 brochure. Probably conservative on both counts.

Quite frankly, the difference is probably minimal in real world terms. Just order what you prefer to drive.

I have a 2009 135i manual.

Next car will be in 2yrs.

[schmeah]

Originally Posted by RPM90

Good info.
I'll be going to some BMW dealers next weekend to get feel for myself.

I'll be looking forward to your comparison. I was very close to getting the MT again (had 335i coupe 6MT) but wanted to try something different. So far I love the DCT. Hopefully you can get a chance to drive both MT and DCT models for a direct comparison. Both are great but I suspect you'll be in a very exclusive club if you go with the MT now since the percentage was already quite small and now a fair percentage of 6MT drivers have gone over to the dark side (dare I say "auto") with the arrival of the DCT.

[///M///M Good]

Originally Posted by RPM90

Good info.
Thanks guys.

I don't see any owners/posters posting about how the N55 manual feels.
I'm interested to see how the manual compares to the N54.

I'll be going to some BMW dealers next weekend to get feel for myself.
It's surprising that BMW rates the manual only .1 sec slower, cause the DCT is one fast trans. I was expecting the DCT to be more than .2+ sec faster, considering the DCT has 1 more gear by which to do an overdrive. BMW could have made 1-5 shorter to get even faster accel times and still used 6th for a decent highway drive gear and 7th for tall overdrive for MPG.

Does anyone have a link to the gear ratios for the DCT and the manual?
I'll check bmwusa.com they usually list them.

Autos weigh more than manuals to begin with - more so with an extra cog. So the extra weight versus the faster shifts and extra ratio appear to be roughly canceling each other out.

[Tessio]

I don't drag race BMWs, so I can't comment on its value there, but in situations where there are a lot of fast, accurate gear changes required like tight tracks and mountainous terrain, where a manual driver has to work his ass off and can lose a lot of momentum on a missed shift, I think DCT would really open up its advantage. I found DCT absolutely stunning in that environment, matching revs almost instantly and allowing me to focus more on steering. Fascinating stuff.

Personally, with my skill level, if my purpose in driving my car was to win races, I'd buy a DCT without question, I simply can't shift that fast that consistently. For now I'm still a manual guy, I just find it more involving. Perhaps it's because I've been driving manuals all my life. It's second nature. Coming from a manual mindset and test driving DCT I find myself first considering it an automatic, forgetting to shift, and getting frustrated with it. Then I concentrate on it I marvel at how fast it can snap them off - Chunk-chunk-chunk. Cool stuff. DCT would grow on me over time I think. I think if I owned one I could see myself remapping mentally and becoming quite enamored of it.