N54/N55 6sp step/7sp dc/8sp step?

[thezone135i]

Juts doing a bit of research for shits n giggs. Im confused as to why there are so many different combinations of the trans and engines in bm's.

I understand the 135is changed from N54 to N55 in 2010 and also moved to a DC trans but why then does the latest M135i have the N55 but with only an 8sp step and the latest Z4 have a 7sp DC but uses the N54?

And the 1M used an N54 even well beyond the introduction of the N55?

[flinchy]

The 1m also used the n55 6MT, which was different to the n54 6MT

yep.

[UR25IO]

Originally Posted by thezone135i

Juts doing a bit of research for shits n giggs. Im confused as to why there are so many different combinations of the trans and engines in bm's.

I understand the 135is changed from N54 to N55 in 2010 and also moved to a DC trans but why then does the latest M135i have the N55 but with only an 8sp step and the latest Z4 have a 7sp DC but uses the N54?

And the 1M used an N54 even well beyond the introduction of the N55?

I could totally be wrong (please correct me anyone if im wrong) I heard that something to do with the N55 DCTransmission not able to hold the high torque/Nm and instead of making it stronger for the new model, they chose to go back to the tradtion Automatic 7/8sp.

I think DCT is the best thing that has ever been created.. lightning fast! lol

[John_01]

DCT transmission works very well in my 135i. In the context of the luxury car market, the DCT is not quite as gentle starting / smooth shifting as a torque converter automatic. I guess that could be the reason why BMW changed back to a conventional auto tranny. If it was me, I'd choose either DCT or a proper manual.

[thezone135i]

Originally Posted by UR25IO

I could totally be wrong (please correct me anyone if im wrong) I heard that something to do with the N55 DCTransmission not able to hold the high torque/Nm and instead of making it stronger for the new model, they chose to go back to the tradtion Automatic 7/8sp.

I think DCT is the best thing that has ever been created.. lightning fast! lol

Thats def not the case as the current Z4 35is runs a 7spd DCT and has 250kw and 450nm stock from an N54.

Originally Posted by John_01

DCT transmission works very well in my 135i. In the context of the luxury car market, the DCT is not quite as gentle starting / smooth shifting as a torque converter automatic. I guess that could be the reason why BMW changed back to a conventional auto tranny. If it was me, I'd choose either DCT or a proper manual.

Im not sure why people dont rate the bmw step. I have driven many VW's with dsg and owned an R32 with a DSG tune and I can tell you my step has less lag between hitting the paddle and acutal change than the vw's. The 135 step is instantaneous even if I drop down 2 or 3 gears at once, brilliant piece of engineering. And the oem software is way more intuitive than the vw's too. Will keep it in 5th if I don't go over 70 and will change down coming in to a corner. The vw dsg in stock form is useless, will change to 6th at 50km/h and stays there until you are half way through the corner and start accelerating before it decides to change down in a panic.

[135i2]

Originally Posted by thezone135i

Thats def not the case as the current Z4 35is runs a 7spd DCT and has 250kw and 450nm stock from an N54.



Im not sure why people dont rate the bmw step. I have driven many VW's with dsg and owned an R32 with a DSG tune and I can tell you my step has less lag between hitting the paddle and acutal change than the vw's. The 135 step is instantaneous even if I drop down 2 or 3 gears at once, brilliant piece of engineering. And the oem software is way more intuitive than the vw's too. Will keep it in 5th if I don't go over 70 and will change down coming in to a corner. The vw dsg in stock form is useless, will change to 6th at 50km/h and stays there until you are half way through the corner and start accelerating before it decides to change down in a panic.

I agree with your thoughts re the BMW Steptronic (mine 6spd) and the VW DSG.

If you have many RWKW then the auto is a good piece of kit here in the 135 and no need for 7 or 8 speeds with 350rw and 3.85 M3 LSD. And it will hold the power standard!

[flinchy]

Can't forget the s63 powered cars run a DCT, and they make boatloads more torque than any of the 6cyl motors

[135i2]

And then there is the DCT Veyron SS....