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Old Wed, May-15-2013, 01:13:38 AM   #2
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Default Re: Comprehensive SMG to 6MT Conversion Thread

20. Now that the plate is off, you have a couple of options. Keep in mind that, regardless of which option you choose, it is very important to prime/paint/undercoat everything to prevent rust in the future since much of the protective undercoating is now ground off. Since I do not own a welder, I decided to try something a little different for attaching the shift arm support bracket. I used quarter inch rivets in tightly clearanced ” holes to mount it. First I drilled three ” holes in the mounting tabs on the bracket. Next I pushed the bracket up into place, and used a sharpie marker to mark where to drill the receiving ” holes. Finally, insert your rivets and attach the bracket. Each of the tabs should sit flush with the transmission tunnel where they mount. After you prime and paint, go ahead and install the cylindrical rubber mount into the bracket that will actually support the rear of the shifter arm. You’ll notice that the shifter arm will essentially float in the rubber bushing, and that this bracket is under little to no stress at any given time.


21. At this point, it’s time to work on the pedal assembly and routing the new clutch hydraulic lines. One flexible hose will run from the unused nipple on the brake master cylinder reservoir, down through a rubber grommet in the firewall, and onto the supply nipple on the clutch master cylinder. Do not cut the plastic end off of the nipple on the reservoir or try to hook up the feed hose until you are ready to bleed the clutch.

For now, simply route the hose and cut it to length. Snap the clutch module into place on the clutch master cylinder, and bolt the CMC into place on the pedal bracket. The best reference for how to do this will be to use the OEM parts diagram for the pedal assembly.

In order to route the hard hydraulic line from the CMC through the floor to the slave cylinder, remove the deal pedal trim assembly. Do this by removing the hood release latch, and then popping the trim out of its clips. Be careful not to break the plastic clips. This will allow you to peel back the carpet and foam padding enough to get the hose down and through the existing hole under the floor. There is a perforated circle in the sound deadening under the car that you can punch out to reveal the removable grommet through which the clutch line will run. I found that the best way to install the clutch line was from under the car, and to snake it up through the carpet and to the bottom of the CMC that way. The clutch line then simply plugs into the bottom of the CMC with a quick connect.

22. Modify the plastic panel under the dash to work with your new third pedal. There is already an outline of the exact profile molded into the plastic, so just follow that path with a cutting tool on a dremel or similar tool in order to cut the slot.

23. It’s time for reassembly! Everything goes back together exactly the opposite of how it came apart. I waited until the transmission was bolted back up to the motor before installing the shift linkage components. Remember to torque each bolt to spec (remember that there is a different torque spec for each bellhousing mounting bolt), use Loctite on your new flex disc nuts (which should always be replaced after they are removed), and to properly preload your center support bearing. Here are some of the important torque specs, per the TIS Manual:

Bellhousing M8 Bolts: 28 Nm
Bellhousing M10 Bolts: 56 Nm
Bellhousing M12 Bolts: 98 Nm
Flex Disc Nuts: 100 Nm (Remember to only physically turn the part that is in contact with the flange, NOT the rubber guibo!)
CSB to body: 21 Nm

24. Cut off the tip of the plastic barbed nipple from the brake fluid reservoir. Before doing this, it is advisable to siphon out the brake fluid to below the level of nipple to prevent brake fluid from running out and down any painted surfaces. Attach the clutch master cylinder supply hose to the reservoir, and proceed to bleed your clutch. Because the lines will be dry all the way through, the manual pump method probably will not get you very far in the beginning. I used a MityVac vacuum bleeder to help draw fluid through the system from the bleeder screw on the slave cylinder. Remember to keep the reservoir full as you do this, or you will be starting from scratch when air is drawn in. Once there is a relatively constant flow of fluid, I was able to finish bleeding the clutch the old fashioned way. Open the bleeder screw, push and hold the clutch pedal down to the floor, close the bleeder screw, and release the clutch pedal. Repeat until each pump produces a steady stream of fluid without air bubbles. You will feel the clutch pedal build up more and more pressure as you eliminate the air from the system.

Procedure (Electrical):

I decided to tackle the wiring completely separately from the mechanical side of the swap. In my mind, this made it a little bit easier to process mentally. Honestly, if you can follow directions and know how to solder there is very little difficulty in the wiring side of this project.

Begin by cut off the two small connectors (blue and red) on the end of the clutch module lead adapter. These will not be needed. The black connector will plug directly into the clutch module mounted on the clutch master cylinder.

Note the male pins that are inserted into these connectors. In order to make the connection to the EWS (pin 3 on the lead adapter), a female pin corresponding to that male pin size will need to be soldered on as pin 8 in the EWS is blank on SMG cars. The same size female pin will also be used in pin 20 on the DME connector in the connection box under the hood, as this is also a blank slot on SMG cars. Note that in order to install the female pins in these connectors, the connectors themselves need to be disassembled. Otherwise, the pins will not “click” into place. Anyway, on to the adapter lead connections:

Pin 1: Br/Sw (Brown w/Black stripe): Ground (tap into the brake light switch on pedal box that has the same wiring colors)

Pin 2: Bl/Br (Blue w/Brown Stripe) -> Pin 1 gear switch -> Pin 2 Gear Switch -> Pin 20 Gr/Bl @ DME x60002.
Connect pin 2 from the clutch switch to the pin 13 wire from the SMG ECU connector (grey 40 pin connector). To do this, you will need to run a length of hookup wire through the same rubber grommet that the clutch master cylinder resevior hose runs through up into the DME connector box. In my case, this is seen as the white hookup wire. I was able to pass it through one of the rubber grommets that another wiring harness passes through to enter the main ECU box.

Next connect the ground connector from the SMG ECU to the DME pin 20 at connector x60002 (24 pin black connector) next to the 9 pin power connector on the engine DME. Note that pin 20 on the DME is blank, and you will need to disassemble it and insert the wire with a female pin that will click into place.

*Note that it is NOT necessary to do anything with pin 2 on the clutch switch in order to get the car to run. This connection is purely for the function of the cruise control in conjunction with the gear recognition sensor that was installed in the tapped M14 hole in the transmission. Also note that even wired correctly, your cruise control will NOT function until the car has been recoded with the proper 6MT tune.

Pin 3: Vi/Ge (Violet w/Yellow Stripe): 12V (tap into the brake light switch on pedal box which has the same wire colors). The following picture shows pins 1 and 3 fully wired into the brake switch module.

Pin 4: Bl/Sw (Blue w/Black Stripe): Pin 8 in EWS (white box in upper lefthand side of driver's footwell. Pin 8 is empty). If you remove the two 10mm plastic nuts that hold the EWS module in the footwell, you will be able to see the pin numbering scheme to be sure you make the correct connection. Pin 8 is in the upper right hand corner of the small pins. Again, in order to insert the female pin into position 8 in the EWS connector, you will have to disconnect and then disassemble the connector itself.


Coding will be the final part of this project, and is the only part that I will not be able to answer specific questions on! The VERY good news is that, provided you completed the wiring per the instructions above, your car will start and will run. You will of course have the SES light and SMG cog light on. My car didn't run in a full-on limp mode, but it was down on power a significant amount. I checked my codes just for the fun of it with my Peake tool, and came up with table 1B, codes B1 and 44. Both of these are related to the lack of communication with the SMG module. As everyone knows, any shop with Autologic should be able to do the coding. I, however, was lucky enough to have a local BMW buddy hook me up! He used a combination of WinOLS, NCS Expert, INPA, and WinFPK (if I recall correctly) in order to read, modify, and rewrite each of the different modules. He took care of the DME, the DSC, the cluster (IKE?), and the EWS. When all was said and done, my car had no engine codes, no more cog light, no more SMG LCD display, but was able to add (retain) the SMG shift lights! He did an incredible job, so thanks again if you're reading this!

Coding FAQ's:

1. Will my car run without coding?

Yes, if you followed the wiring instruction for pins 1, 3, and 4 of the clutch module correctly, your car should run. However, you will be left down a significant amount of power and with both CEL and SMG cog warning lights.

2. Will I lose my tune (Dinan, Evolve, etc.) when I have my car reflashed?

No, it can be done without overwriting your tune.

Gear Position Sensor Delete:
If you choose to not install the Gear Position sensor, you need to short the gear position sensor wire together OR wire the clutch switch directly to the DME. Additionally, you need some software modifications

1) Set K_SKRAFTS_CONTROL to 02 (default should be 01). This is located at 0x4028 on the MSS54 and 0x802A on the MSS54HP

2) Set K_S_GANG_LL_ED to 0xFFFF (default should be 0x0032). This is located at 0x35AE on 1701/2101, 0x35DA on 2801, 0x5952 on 2001/2701, and 0x582E on 0301/0401 (CSL)

3) US cars: Set K_MD_MIN_VERH_KRAFTS to 0xA0. It is located at 0x67E0 on 2801 (MSS54). It is located at 0x88A2 on 2701 (MSS54HP). Default value is 0x80 on US cars (Euro cars are already at 0xA0).


Now that all is said and done, I am totally in love with the M3 again. In my opinion, this is hands down the best modification anyone could make to an SMG car! It is a great feeling to have successfully gotten through a project like this, and it is fantastic having the piece of mind that comes with bailing on the SMG pump. The car now shifts absolutely flawlessly, as it should since every 6MT component from the shifter bushings to the clutch cylinders are brand spanking new. Remember, this can all be yours for less than the price of a new muffler

Last edited by terraphantm; Wed, Apr-25-2018 at 08:55:32 PM.
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