Correct, need DTC fully off for 6, but still need temp/mileage requirements for LC to activate. Everything else is standard M-DCT functioning (i.e. no engagement until accel pushed, start-assist brake release after 2 secs, etc.).
N54 DCT w/M3 Conversion
- Thread starter dyezak
- Start date
So that doesn't go through the drivelogic levels at all then. Just straight to level 6 with that green Indicator?
The sixth bar only becomes available when the DSC is off. You still need to push the up drive logic button to get the sixth level active from what I recall
Easiest way to see the extra shift logic level in action is to already be in Manual mode, then you will see the 6th bar appear once DSC is fully off. It's like adding an 11 to the volume knob!
I've been pretty happy with the LC of the MDCT. Way more consistent than the 135 programming. I do a lot of Autocross, so short distance between each launch, but enough for it to come on at the start line every time. I completely forgot to log the launch to see what it was doing. With the PS2, the car bogs on me at the 3500 rpm launch setting. The factory would light the tires up. The PS2 lights them up later.
I kept getting in a hurry and forgot to use the cruise stalk to bump up the RPM limit to 4000 or 4500.
This was the best upgrade to the car.
Thanks. I'll try playing around with higher rpm settings with Launch Control and see how that does. My issue may very well be my newbie tuning attempt. With the factory turbo, a foot to the floor, past the downshift click, would result in a 3500-4500 launch with spinning tires. Now it results in a firm launch with grip, falling on it's face for a bit and then back on it again. I just assumed it needed help spooling.
Huh, I looked again and WGDC Spool starts late (marker).
I'll find a tuning thread to continue this quest. Maybe there is a Spool RPM Min setting.
Easiest way to see the extra shift logic level in action is to already be in Manual mode, then you will see the 6th bar appear once DSC is fully off. It's like adding an 11 to the volume knob!
I've been pretty happy with the LC of the MDCT. Way more consistent than the 135 programming. I do a lot of Autocross, so short distance between each launch, but enough for it to come on at the start line every time. I completely forgot to log the launch to see what it was doing. With the PS2, the car bogs on me at the 3500 rpm launch setting. The factory would light the tires up. The PS2 lights them up later.
I kept getting in a hurry and forgot to use the cruise stalk to bump up the RPM limit to 4000 or 4500.
This was the best upgrade to the car.
you have probably answered this somewhere, but what diff did you end up going with?
I picked up a BMW "performance" diff 2.81 ratio (a split of difference between the 2.56 and 3.15). I prefer the clutch style diff and at the time it was the most convenient. It's for a 235i or 435i, but all you have to do is use your rear cover and it fits. <- assuming E90/92 or E82.
Also, earlier this year BMW started to clearance them out.
From $2200 down to $800. I think Turner was selling them at that price.Thank you!I picked up a BMW "performance" diff 2.81 ratio (a split of difference between the 2.56 and 3.15). I prefer the clutch style diff and at the time it was the most convenient. It's for a 235i or 435i, but all you have to do is use your rear cover and it fits. <- assuming E90/92 or E82.
Also, earlier this year BMW started to clearance them out.
so it drives fine with the 2.81? No driveshaft modifications needed? I am still crossing my fingers someone will figure out how to get this to work with the 2.56, but this 2.81 may be the next easiest alternative.
More importantly 800 bucks ... I can’t find a used lsd for less than 1000.
Hi,
I'm building up parts to do this on an 09 DCT in the UK. Already have the GWS and the Knob. Looking for a cover and now diff
Would this diff work with the cover changed like mentioned above. There's also 335d diffs at 2.81 but with higher mileage etc.
I'm building up parts to do this on an 09 DCT in the UK. Already have the GWS and the Knob. Looking for a cover and now diff
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Would this diff work with the cover changed like mentioned above. There's also 335d diffs at 2.81 but with higher mileage etc.
Were there any posts on getting the steering wheel button to function as the M button?
Yes. But only the DSC disable and not the rest of the settings. It would t be a far stretch once we have m3 logs though
Yes, 2.81 works well. I don't have any good logs readily available to show the fast shifting. I have plenty showing how slow it is with the 2.56.
Hi,
I'm building up parts to do this on an 09 DCT in the UK. Already have the GWS and the Knob. Looking for a cover and now diff
BMW 140i Rear Differential Diff 7603759 Ratio 2.81 for sale online | eBay
Find many great new & used options and get the best deals for BMW 140i Rear Differential Diff 7603759 Ratio 2.81 at the best online prices at eBay! Free delivery for many products!rover.ebay.com
Would this diff work with the cover changed like mentioned above. There's also 335d diffs at 2.81 but with higher mileage etc.
The unit from a 335d will go in without any changes. I'm not so sure on the newer 1 series. If it is running the same sub-frame as the 2 series then it'll work.
My testing went this way:
1. Buy a high mileage 3.08 bolted diff from a junk yard (I have the proper part number somewhere for the 2007 year model unit)
2. Does it resolve the shifting issue? YES
3. Is freeway rpm too high? YES
4. Borrow 3.08 diff from a 240i
5. Measure for dimensions
6. Will it fit? NO, rear cover is different
7. Is pumpkin same? YES
8. Swap cover from E90 3.08 unit
9. Does it fit? YES
10. Order 240i/440i LSD from BMW
11. Install and have fun? YES
12. RPMs too high? not bad, but lower would be better for spool
My driving was limited to just limp mode down to the filling station and back. (limp mode is due to other work going on not the DCT changes)
Nothing seemed unusual at such casual driving.
yes - I am on the stock 2.56 diff
Well I posted on the development thread but maybe this is the more appropriate place for it. I've started compiling my parts for this endeavor for my n55 135 and am absolutely stoked!
Thank you guys so much for all the information that you've worked so hard on to share with the community. I'm not sure how many others actually have seen this in the time that it's been out, but I for one am very grateful!
Thank you guys so much for all the information that you've worked so hard on to share with the community. I'm not sure how many others actually have seen this in the time that it's been out, but I for one am very grateful!
