M3 DCT Wiring Diagram

Jake@MHD

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From that thread that J Colley Linked to ... All of the messages for the DKG, including torque request. This means that we can actually tell the DKG that more torque than actual is being delivered. This means we can increase clamping pressure up to the limit. We just dont know what the limit is... Am i correct in my assumption?

No need to manually send the CAN packets for torque. The DME already sends them, and you can max what is sent via the existing XDF tables.
 

dyezak

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No need to manually send the CAN packets for torque. The DME already sends them, and you can max what is sent via the existing XDF tables.

Correct, but there is a max value for torque. I can't remember what it is. But use this as an example...lets just say the max value is 1000 units (whatever that unit may be):

DKG receives tq = 1000

***DKG calculates line pressure = (tq x 0.8)/14.7 = BAR (we don't know what this formula is, but we know it exists)

Our maximum would yield 54.42bar in this instance. The transmission has a maximum of 90bar line pressure according to Getrag. So no matter what we did with the DME tune we could never max the transmission's line pressure (i.e. clutch holding pressure).

That formula exists and for us to understand what our limits are we need to pull the BIN, unencrypt it, find it, the decypher it. Then we can see what the DKG is actually doing with the TQ value we pass to it. If we could change the formula so that our max TQ = max line pressure...that would be the holy grail!
 

Jake@MHD

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Correct, but there is a max value for torque. I can't remember what it is. But use this as an example...lets just say the max value is 1000 units (whatever that unit may be):......
................

It has nothing to do with a formula. Torque is sent to the DCT TCU, the TCU uses the torque value sent as an axis lookup value in a table, and the table spits out clamping pressure. I'd imagine that much like the AT TCU, it is these internal TCU tables that are in fact limiting clamping pressure. Sending max TQ from the DME is getting you everything you can out of the DCT stock calibration. You will need to reverse engineer the DCT TCU, find the appropriate tables, and raise the right most cells to a higher line pressure.
 

dyezak

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It has nothing to do with a formula. Torque is sent to the DCT TCU, the TCU uses the torque value sent as an axis lookup value in a table, and the table spits out clamping pressure. I'd imagine that much like the AT TCU, it is these internal TCU tables that are in fact limiting clamping pressure. Sending max TQ from the DME is getting you everything you can out of the DCT stock calibration. You will need to reverse engineer the DCT TCU, find the appropriate tables, and raise the right most cells to a higher line pressure.

Absolutely. Nailed it.

Hence our pressure on anyone who will listen (MHD, xHP, MagicMotorsports, God, the bum on the street) that this transmission is used in TONS of high end sports cars where people would pay good money for a solution:

M6
M5
M4
M3
M2
335is
z4 35is
135is
335i (non NA market)
135i (non NA market)
235M

Plus all the non-BMW uses of this transmission too. You are looking at a potential market population that dwarfs anything xHP or MHD have targeted combined and then multiplied by a factor of 4-5.

xHP, MagicMotorsports, and MHD have all proven their technical acumen...

And all have shown they are absolutely lousy at the business side of running a business. Magic won't respond to emails and requests, xHP can't forecast potential revenue based on business development, and MHD undervalues their product based on obvious market input and sits back complaining how they don't have the money/time to move development faster.
 

Tippin

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Oh, and I doubled down on this conversion. I am assuming the ZB file from the M3 will also contain the M3 final drive ratio for the DCT (3.15). That should mean that we can run a 3.15 or higher (up to our stock 2.56) rear ratio with no issues.

So I bought an M3 DCT Rear Diff setup in preparation for this going well.
Do you have any updates to confirm if this is going to be possible? This plays a huge role in whether or not i DCT swap my car this year as I want t 3.15
 

NoQuarter

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Been looking this over for the E89 Z4.

The first thing is to make sure the new shifter doesn't look like a hack job. Getting the M3 shifter in there may work but the trim is a problem. The M4 shifter looks more likely to work with the trim bits that are available but that shifter expects 2 PT_CAN connections (instead of a single PT_CAN and LINbus).

The sport button goes to the FRM module (instead of the GWS). If i were to try this, I was thinking keep the existing sport button connected as is to the FRM and add the new drivelogic button to the GWS would be the way to go.

Either way, this project has a good bit of extra trim fabrication to deal with for the Z4 it seems. I suppose mashing together bits of the trim hear and there then fiberglass work to blend it all together then a paint job or vinyl wrap.

The second PT-CAN and the Linbus connections are just a backup, I wonder if there where the error shows up if one of them was actually left unused.
 

aus335iguy

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I’ve been waiting for a z owner to have a crack at this. Is your car a Z435is? The reason being that those cars are the closest thing to an n54 M car that we have with multiple modes for engine, steering, suspension traction control and gearbox. M drive should be able to get working more easily as a result
 

NoQuarter

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I’ve been waiting for a z owner to have a crack at this. Is your car a Z435is? The reason being that those cars are the closest thing to an n54 M car that we have with multiple modes for engine, steering, suspension traction control and gearbox. M drive should be able to get working more easily as a result

yep - 2011 35is.

I have created my own canbus box in the past to display obd info on the cic screen and control the interface via the Idrive knob. Retrofitted M5 Active Backrest, flashed my trans to Sport Auto, upgraded the old idrive knob to the new multi-button, I have MHD on my Z4 cic screen... etc. what I am trying to say is I have a chance to make this happen :)

The fabrication of the trim for the gearshift though is out of my skillset unfortunately. The M4 shifter seems to only be available new also.

We'll see how far I am willing to take it. It has to look like it belongs.

Edit:
The shape of this trim is what I was imagining to be a big problem.
qS_2_6_dqawhFB-vS9NGvJWgXNT00TF5ljVhZcECPfbx3uO-M19KFOSF1sPyA?width=371&height=660&cropmode=none.jpg


xJ6EANYqljNn4nMkbUJqkQpQ5s-355tvqoFjQbu-lXtb0lBoCN4gzblQU61vw?width=660&height=371&cropmode=none.jpg


But it seems I could remove the gator and the blue plastic frame and attach it to the M3 shifter somehow. You guys with the M3 shifter think this would work?
 
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NoQuarter

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Another Z4 related question, then i will start a new thread if I order some parts

For the M3 shifter, is the curved base shown in red detachable from the actual controller marked in blue?
Or will I need to somehow install the entire assembly?


M3 Shifter.PNG
 

aus335iguy

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I think you can but I don’t think you’ll need to. If you remove the console cover you might find that it looks like exactly the same size and shape as the m3 version.

I just checked and the Z4is GWS is the same part as the 3 series so M3 version should theoretically mount straight up
 
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