There's a lot of good information in that document above. It is a high level description of the system, but gives some details showing some more of the obstacles to focus on. Noted so far:
- LIN Bus communication between GWS (gear shift) and DKG is for redundant communication of PT-CAN data.
- Rules out the notion that the E60 gear shift can be retained
- Drive logic switch consists of two simple grounding switches. Same as E60 to retain SMG trim piece?
- Possible to retain SMG surround so that power/DSC/EDC buttons/wiring modifications can be avoided?
Transmission oil cooler: There are two, oil to coolant and oil to air; receives coolant from a cylinder head to the cooler, then pumped back to the coolant system. This is used to warm up the DCT oil. Once the oil is above 203 degrees, oil thermostat directs oil flow to the oil/air cooler instead.]
- Need to identify controlling scheme for the coolant circulating pump. Is this from the DCT controller?
- Need to identify a location to to tap into S85 coolant system for coolant supply from engine for warm coolant as well as a return point.
- Custom coolant line fab likely required.
- some info from IND
- Oil Calibration routines: Something I hadn't considered until reading this, but just like SMG adaptation, DCT requires some similar functions. How to access these? Obviously DIS/ISTA are not an option. Will INPA allow calibration of DCT via E9x menus or error out before getting there. A custom INPA .IPS can be compiled to a standalone .IPO file dedicated for this, but will require some research.
- Significant number of KOMBI warning symbols not native to E6x KOMBI. Unknown what will display if anything when DCT signals these errors or what safety info will be provided. Worth pursuing E9x KOMBI retrofit? Note that the manual lists "check control message" with a 3 digit number. Perhaps these can be used in tracing?
- Random mention that the stock diff ratio is 3.154:1 for DCT. This changes the overall drive ratio back to very close to stock, somewhere in between an E60 with a 3.62 and a 3.91. Perhaps the ring and pinion for the M3 are compatible in the E60 housing? Anyone willing to contact a diff builder on this one?