Yet another Auto to DCT swap

Brett Shepard

Lurker
Nov 5, 2016
17
Jacksonville
Thanks to everyone's previous efforts, I just completed the DCT with M3 GTS flash swap on my 2010 auto 335i. I'm using the MFactory lightweight flywheel, M3 diff and axles with carbon fiber driveshaft. Everything was pretty straight forward. I did have some issues with another install of ncsexpert that I thought I removed. Ncexpert and NCS Dummy were looking at two different work folders. I had to swap pin 8 of x6031 to pin 10 on the trans harness for it to correctly communicate P/N position.
I only swapped the DCT, GWS, center console with drivelogic switch so far. Coded Kombi, DSC, JBBF and CAS. I have all 6 modes of drivelogic in manual mode. I have some tuning issues to work out before I can run it hard but shifts great through all gears at mid and part throttle. I looked up the SZL and I believe the one currently in the car will allow adjustable launch control. I'll verify in the next few days. Again, thanks for the efforts of everyone involved in this project! Feels like a new car!!
 

aus335iguy

Lieutenant
Nov 18, 2017
931
Well done, you’re one of very few people who’ve completed this succesfully
You didn’t use the m3 DSC, Kombi or SZL. That’s interesting.
 

L€X

New Member
Dec 30, 2018
8
Hello!
Thanks to everyone's previous efforts, I just completed the DCT with M3 GTS flash swap on my 2010 auto 335i. I'm using the MFactory lightweight flywheel, M3 diff and axles with carbon fiber driveshaft. Everything was pretty straight forward. I did have some issues with another install of ncsexpert that I thought I removed. Ncexpert and NCS Dummy were looking at two different work folders. I had to swap pin 8 of x6031 to pin 10 on the trans harness for it to correctly communicate P/N position.
I only swapped the DCT, GWS, center console with drivelogic switch so far. Coded Kombi, DSC, JBBF and CAS. I have all 6 modes of drivelogic in manual mode. I have some tuning issues to work out before I can run it hard but shifts great through all gears at mid and part throttle. I looked up the SZL and I believe the one currently in the car will allow adjustable launch control. I'll verify in the next few days. Again, thanks for the efforts of everyone involved in this project! Feels like a new car!!
Hello! I swaped m3 gts gws, szl, dsc and m3 gts soft. But launch control and shift lights don't work yet. Do you know some one Who did that successfully?
 

aus335iguy

Lieutenant
Nov 18, 2017
931
Great to see that other people are doing the swap. I’d like to help you but dont know where to start.
@Brett Shepard How did you get on ?
@L€X I dont think anyone has the shift lights working. Launch control should work though
 
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L€X

New Member
Dec 30, 2018
8
Great to see that other people are doing the swap. I’d like to help you but dont know where to start.
@Brett Shepard How did you get on ?
@L€X I dont think anyone has the shift lights working. Launch control should work though
Ok, thanks, i Will try something else. Now i have mdm Mode lol, but its doesn't work as it should
 
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Stokes

Corporal
Jan 26, 2018
125
Houston, TX
No, i use stock diff 335i dct 2,56 ratio and flash m3 gts trans. Also i use m3 gws, dashboard, dsc and szl
Unfortunately, the 2.56 ratio diff will cause super soft, laggy shifts at higher speeds when running the M3/GTS DCT setup. Ends up that a 2.81 is a happy medium between 335is/135i DCT programming and M3 DCT programming.
 

Brett Shepard

Lurker
Nov 5, 2016
17
Jacksonville
I've had very little time to do more than drive the car a couple times. I haven't tried launch control yet. My understanding is that you won't be able to get the shift lights to work. I should get back to working on the car in the next couple weeks.
 

L€X

New Member
Dec 30, 2018
8
Unfortunately, the 2.56 ratio diff will cause super soft, laggy shifts at higher speeds when running the M3/GTS DCT setup. Ends up that a 2.81 is a happy medium between 335is/135i DCT programming and M3 DCT programming.
Are you sure? I didn't Drive fast yet, but looks like 2,56 diff is Ok... What type of diff do you have?
 

Stokes

Corporal
Jan 26, 2018
125
Houston, TX
Are you sure? I didn't Drive fast yet, but looks like 2,56 diff is Ok... What type of diff do you have?
I thought the same until after 4th year at full throttle. I tried resetting transmission adaptations and all kinds of other things. In the thread on the conversion, it was discovered (not by me) that the ratio was outside parameters. I tried a used 3.08 diff and wow, hard shifts from 4th gear and up. Someone else verified the 2.81 would work, then I bought a 240i bmw lsd (2.81) and swapped my cover with it. The 3.08 was to high on the revs for me.
 
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Stokes

Corporal
Jan 26, 2018
125
Houston, TX
The BMW Motorsport LSD didn't sell well as a dealer install. I think originally it was a $4k option. Mine was $2.2k when I picked it up (no core required). Ends up the pumpkin is the same, just the rear mount is different but resolved with using your original cover.

It's basically an old school clutch type (25%) in the same wierd casing that they use for non-M cars. I'm wondering if I can add a third clutch disc like on previous gen diffs and even machine the cap and get 4 disc's in there?

Not as strong as the M diff or the 100% variable lock up either. I wasn't ready to go full M.
 
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