DIY: MK20 -> MK60 Swap

[heinzboehmer]

Preface

Have a couple things to say about this before getting into the actual DIY, so I'll get that out of the way first.

1. This is not an easy or quick job.

• I knew it was going to be a lot of work before starting and I was still greatly surprised by how much time I ended up spending. With that in mind, I really do not think this is a worthwhile swap, unless your car is fully sorted otherwise. I decided to do it because it would have probably taken me longer to do everything I've already done to mine on another car, but that might not be the case for everyone.
• The parts required are not exactly cheap, so it's totally possible that selling your MK20 car and getting an MK60 car is the better choice.

2. Because this is so much work and is very much not a beginner project, I will not be writing up a typical step by step DIY.

• I'll make sure to cover everything necessary, but will also assume that anyone following this has some decent "working on cars" skills.This guide will be split into three parts: mechanical, electrical and coding. I found that was also the order of most difficult to less difficult, so plan accordingly.
• Due to what was covered above, this guide is likely to be very direct and 'referenc-y". I have some posts that are much more conversational in my journal. It's probably worth reading through those too if you plan on attempting this.

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Mechanical Work

There are multiple approaches to this swap. I'll list them out below in ascending order of difficulty.

1. Sell your MK20 car and buy an MK60 car.

• This is by far the easiest and most sensible option. Not very rewarding, but will save you a ton of time and effort. Will also only be a bit more expensive than going through with the swap.

2. Install the MK60 module in place of the MK20 module.

• This requires very little brake line work and can probably be done in an afternoon. However, you will not get any reduction in complexity or weight. Additionally, there's talk about BMW placing the MK60 module closer to the brake master cylinder for reasons (response times?), so having it in the "wrong" place might not make it behave optimally. To do this, you would need to add unions and bend short bits of brake lines for the two lines that plug in on the side of the MK60 valve block.

3. Bend and route new front lines, but splice into the rears.

• This option is probably the best compromise of work and "correctness". The MK20 rear brake lines have unions right by the steering column. It's possible to unbolt these and then just run new lines from these unions to the new MK60 location.
• Pic of the factory unions:

4. Remove ALL brake lines and run new ones.

• This is what I decided to do and what I will be covering in this thread. It's the most involved approach, so any of the previously mentioned approaches should become obvious after reading through this.

Steps:

1. Gather parts.

• The most cost effective way to do this is to find a crashed car that someone is parting out and buy everything from them. There are also some sellers that sell "kits" on eBay (and similar), but they tend to be more expensive.
• RealOEM is your friend. Go look at the front brake pipe and rear brake pipe diagrams for MK60 cars and buy everything you need from there. Most useful bits are the brake lines (of course) and the spacers/brackets.
• Don't forget one time use things for everything that need to come out (exhaust gaskets, guibo nuts, driveshaft gasket, etc.
• Pic of everything I bought:

1.5. (If necessary) Refurb your used MK60 bits.

• You will likely get your used parts covered in brake fluid. Brake fluid is the absolute worst and will eat everything it touches. This means that you might need to touch up/fully repaint some of your parts.
• Eagle eyed viewers will notice that the MK60 pump motor in the previous pic is silver. This is not some special edition MK60, but rather the result of me stripping off all the old paint from it because it was severely bubbling. I later refinished this with POR-15.

2. Jack up your car (as high as it will go or use your lift if you're fancy), take wheels off, put wheels under car, use jack stands, don't do sketchy shit and crush yourself, etc. It's a good idea to disconnect your battery too.

3. Take your engine bay apart.

• Remove as much as you can so that all the MK20 brake lines are visible. This includes —but is not limited to— the following:
  • Strut bar
  • Cabin air filter housing
  • Cover for blower motor
  • Intake
  • Engine beauty cover
  • Any wire harnesses that run to the DME area
  • Everything in the DME area (electronics, plastic brackets, DME fan, etc.)
  • Brake pedal
  • Underside plastic panels
  • Fuel filter cover
  • V brace
  • Exhaust
  • Handbrake cables
  • Heat shields
  • Driveshaft
  • Gas tank (!)
  • Note: removing the rear subframe might make your life a little easier, but I found no need to do it

4. Gas tank removal.

• This is annoying enough that I figured I should spend some time on this.
• You want to run the gas tank as far down as possible. This will make it lighter during removal and less prone to spills.
• If you parked your car directly onto the jack stands, chances are your fuel system will still be pressurized. There's a schrader valve right by the fuel filter that you can use to relieve fuel pressure. Fuel will come out, so be prepared to catch it.
• First thing to do is go into the interior, remove the lower part of the rear seats and open up both access covers. Once that is done, disconnect all fuel lines and electrical connectors that you see. If you didn't relieve the fuel system pressure, you're going to spray fuel everywhere, so be aware.
• Now undo the flexible bit of the fuel filler hose. This is a great opportunity to replace this, as it will probably be crusty from having spent 20 years on the bottom of a car.
• After that, go underneath the car and remove both straps and the one nut holding the fuel tank to the body. Drop it enough so that you can access the rest of the lines and remove them. Obviously take care when lowering the tank, but the lines are flexible enough that you can drop it a good amount.
• To remove the tank, you need to swear a bunch at it and then realize that the fuel filler neck is catching on the passenger upper control arm. Angle the tank in such a way that the filler tube clears the control arm and then pull towards the front of the car.
• Seal up any ports on the tank and fuel lines hanging from the car. I used a combination of rubber gloves, zip ties and masking tape. Gas vapors are highly flammable and you really want to keep their combustion internal to the engine exclusively.

5. Rip out all the old MK20 brake lines.

• First empty out all the brake fluid in the lines. I used my pressure bleeder (with nothing in the chamber) to pressurize the system and push out all the brake fluid. It worked great.
• The clutch line does not need to be fully emptied, you can just disconnect it from the reservoir and cap it off.
• Cut/unbolt all the brake lines that you see. These will not be reused (well, unless you're not fully replacing everything), so don't be afraid to be destructive. The only thing you want to keep intact is the line that runs above the subframe. This one is short enough that you can easily use it as a template for the new lines.
• Example of my own destructive disassembly:

6. Rip out the rest of the MK20 stuff.

• Unbolt the module from the drug bin.
• Unbolt the booster and master from the interior of the car. The accumulator is connected to the master, so unbolt that from the chassis as well and don't forget to disconnect any electrical connectors.

7. Prep the chassis for the new module.

• Early cars have an extra tab on the chassis beneath the brake booster that interferes with the MK60 module, so cut that off. Bending it out of the way does not give enough clearance, it must be cut.
• Make sure to treat any exposed metal appropriately.
• Pic (tab was in the lower left):

8. Bolt the new MK60 module in temporarily.

• Fortunately, the one threaded tab used to mount the MK60 module is already present, so all you need to do is reuse the accumulator bolt to bolt it up.
• This is just to make sure there's enough clearance for everything. You will likely end up removing it a bunch of times, so just thread the bolt in by hand.
• Leave the thing there, as it will serve as a reference point for bending the brake lines.

9. Bend (and potentially flare and terminate) the lines.

• This is easily the most time consuming part of the whole project.
• If you bought the BMW lines, then they will come pre-flared and cut to length. This is great because you don't need to worry about those things, but it also means you will need to be very precise with your bends or else the finished lined will be too long or too short. I bent my rear lines twice because of basically this.
• If you don't have a good 3/16" bender, get yourself one. I bought the Ridgid 403 bender and it worked great.
• Whenever you bend a line, make sure the threaded bit is at the very end, otherwise you'll have to start from scratch. I used some masking tape to make sure they stayed where I wanted them and did not sneak up on me during bends.
• The line that runs above the subframe is the one line that you technically do not have to remake. It is exactly the same on MK20 and MK60 cars, but I was already remaking everything, so I figured I would do this one too. It's short enough that you can use the old line as a guide:

• I found these white spacer clips to be super useful when lining everything up so that the line could be duplicated:

• The rest of the lines are a pain. You will have probably destroyed the original lines out of frustration upon removal, so you will have little to no reference to base yourself off of. I used the many pictures in Casa de Mesa 's journal to guess at what the lines should look like.
• For the rears, start at the MK60 module and work your way back. Do not try to start at the calipers (ask me how I know). If you do, then it will be basically impossible to stuff the bender in for the bends that go to the module.
• I used a clothes hanger to get the bends correct and then duplicated them on the line.
• Note: One of the rear lines (I forget which) has different sized threads on each end. Make sure you get the orientation of it correct, otherwise you'll be redoing a bunch of work. I walked over to the module and made sure the correct end would screw in to be 100% sure it was all good.
• Repeat this process for the front lines. The coat hanger is yourself.
• Don't get discouraged if you have to redo any of this. It's a pain to get something in this part of the project wrong, but the lines are cheap and it's probably better to have to rebend some stuff than to end up in a wall on your test drive.

10. Go back over your lines and make sure everything is where it should be.

• These are hard lines, so it they're not bent at the correctly angle it's possible that the lines will want to jump out of some of the holders or will be rubbing against stuff.
• Fortunately, the lines are soft enough that any clearancing can be done with your fingers.
• Make sure to use the clips that you bought earlier! These will make it so that the lines are soldily held to the body and don't rub against stuff.

11. Run sanity checks.

• Hook up a source of compressed air and make sure that there are no obvious leaks. I pressurized my pressure bleeder to 20 psi and left it for a while. If no leaks, you're probably good to go.
• Here's mine initially:

• And after 22 hrs:

• Dropped ~0.4 psi (temp corrected) over 22 hrs. Was happy with that so I continued.

12. Install new booster and master cylinder.

• Should be easy since you removed all the DME stuff.
• This is also probably a good time to reinstall the brake pedal.

13. Tighten everything down.

• Make sure all junctions are torqued correctly before you start filling things up with brake fluid. Brake fluid sucks and you really don't want it spraying at high pressure everywhere.

14. Fill the system up with brake fluid and run more sanity checks.

• Fill up and bleed everything in the standard order (RR, RL, FR, RL, clutch).
• Wedge some wood between the seat and the brake pedal (tightly) to pressurize the system.
• Come back the next day and check all the junctions. If you see no fluid leaking out, then you're good! If you do, sell the car and buy one that came with an MK60 from the factory.

15. Adapt the MK20 brake booster vacuum line so that it fits the MK60 booster.

• The MK20 line is longer than the MK60 line, which means that this is one of the few things that you can modify and not spend money on (yay).
• Labeled pic:

• You should cut right where the razor blade is. I used the razor blade for the cut and it sucked. You should use PVC cutters instead:

• Crimp the thing onto the MK60 check valve and you're done:

16. Resist the urge to put too much of the engine bay back together.

• Intake, beauty cover and other things like that can go back on, but don't over do it. There's still wiring to do and you'll need access to the MK60 module for that. Just remember that it is extremely annoying to disassemble something that you just reassembled the day before.

17. Swap out the wheel speed sensor connectors.

• The sensors are different between the two systems so you need to swap the plugs.
• Fortunately the pins are the same so only the connector housings need to get swapped.
• Unpin the old connectors and move the wires to the new connectors, make sure they are in the same spots.
• The front connectors will have three wires running to them, while the new plugs are only expecting two. The middle back one (pin 3) is a ground that is not needed on the MK60. I added some heat shrink around mine and tucked them out of the way.

18. Put the rest of the car back together.

• Assuming you have no leaks, you should be good to reassemble everything underneath the car.
• Gas tank, driveshaft, heat shields, exhaust, v brace, plastics panels, etc.
• I'm going to do the annoying thing and say that reassembly is the opposite of disassembly.

19. Test your brakes.

• Depending on how brave you feel, you can either do this while still on jack stands or with the car on the ground.
• Put it in gear and make sure that pressing the brake pedal means that the wheels stop spinning.
• Chances are that your pedal is going to feel terrible (everything was just recently filled with air after all), so don't worry too much about it. Should only be an issue if it's limiting your braking ability.

20, Make a mental/physical note to bleed your brakes again soon.

• Don't do it immediately. Instead, drive the car around a bit to coerce any stubborn air bubbles into moving through the brake lines, then bleed the brakes again.

21. Test your brakes (again).

• Go out and test your work.
• There will be a million lights on your dash. Look at them for a bit and then tell yourself that this is how old BMWs are and ignore them.
• First make sure that the car stops at slow speeds. If that's good, then progressively start moving up.
• Once you're confident that you can stop, find a quiet street and get up so a decent speed (~45 mph or so) and brake hard. Don't overdo it since ABS will not be working yet. All you want to confirm is that the car brakes straight and doesn't do any weird pulls to one side or the other when depressing the brake or letting go.
• If it all feels exactly the same as before then you're done with the mechanical stuff!

[heinzboehmer]

Electrical Work

Everything the MK60 needs can be found at the MK20 plug, with a few exceptions (TPMS reset wire, M track mode wire, DSC sensor wires). This means that there are also a couple approaches to the wiring:

1. Cut off the MK20 connector and extend the wires over to the MK60 location.

• This will work, but you might have to get creative with the wiring. You could just throw it across the engine bay, but this will make working on the engine kind of a pain.
• The other option is to pull the MK20 wires back into the interior and run your extensions behind the dash. This will also work, but will be very annoying to troubleshoot and then you'll end up with ~40 spliced wires under your carpet, which sounds kinda sketch.

2. Swap an entire body harness over from an MK60 car.

• This will yield the most "factory" install, but requires that you find a harness that fits all of your cars options and remove the entire interior for install. I chose not to do this because I don't really have the space to take the entire interior apart.

3. Make an adapter harness that plugs into the MK20 connector and maps everything over to the correct spots on the MK60 connector.

• This is what I chose to do and what I will go into below. I ended up building a quick PCB to keep things organized and minimize the chances of stupid mistakes, but it's not necessary.

Building the harness:

1. Get the male MK20 connector.

• Unfortunately this is part of the entire case, so I had to buy another MK20. Found one on eBay off a non-M for not too much money though.

2. Unsolder the board from your donor MK20.

• This is fairly simple to do. Solder sucker and an iron will get this free in a few minutes.
• I didn't really care about this board, so I unsoldered the connector connections and then ripped the solenoids wires out. If you care about preserving these, you should unsolder them too.
• Solder and board removed:

3. Cut connector from housing and clean it up.

• I tried cutting a slit in the plastic and heating it up to bend it and form a fourth "wall", but it immediately snapped. I ended up just gluing the piece in place.
• Cleaned up connector:

4. Design the adapter PCB.

• You can skip this step if you are just going to solder directly onto the connector, but I highly recommend going with a PCB, as it makes life much easier.
• This is mine (from before I cleaned up the connector). If anyone wants the Gerber files, just let me know.

5. Get all the rest of the stuff.

• You'll need the following:
  • MK60 connector
  • Brake fluid level sensor connector
  • Brake pressure sensor connector (x2)
  • DSC sensor connector
  • New style wheel speed sensor connectors (x4)
  • Large MK60 power and ground pins (x4)
  • Large MK60 power and ground seals (x4)
  • Small MK60 pins (x31)
  • Small MK60 seals (x31)
  • Small pins for sensor connectors (x12)
  • Small seals for sensor connectors (x12)
  • Wire

• Unfortunately I do not know the part numbers for most of this stuff. I just bought this kit: https://tulayswirewerks.com/product/...connector-kit/
• I also found that 2.5m of wire length for each pin was enough for the harness to go from the MK60, through the interior, behind the dash and to the MK20 connector.

6. Cut and pin all the wires.

• I bought different colored wires, so I built a quick spreadsheet (attached below). mapping wire colors to pins. This let me know how many of each I needed to build.
• There's multiple twisted pairs. Since the wires twist, the effective length decreases slightly, so I built those first (out of 2.5m of wire) and then cut the rest of the wires to that length.

7. Do the adaptering.

• I started at the MK60 connector and clipped in all of my newly pinned wires according to the spreadsheet I built.
• Then I stretched the harness out and held everything together with some tape. This helped do some final trimming of the wires at the PCB end.
• Note that there are some wires that do not run to the PCB (this is reflected in the spreadsheet).

• Soldered the wires onto the board and the board onto the MK20 connector:

• One last thing I did was add some heat shrink around the MK20 side so that it wouldn't short out against the chassis. This is not pretty and I do not like it. I'll make this better in the future:

• And finally here's a pic of the wiring mapping. Pins 1, 16, 32 and 47 (two power, two ground) require 2.5mm² wiring, everything else is 0.5mm². This info was pulled from TIS and is also in the attached spreadsheet.

8. Test your work.

• Connect your harness to everything and make sure it all works. You'll need to code the car to test it, so come back to this step after reading through the next post.

9. Make things pretty.

• Wrap your harness in tesa tape (or equivalent) and route it somewhere where it's not annoying and won't get damaged.

10. Swap out the DSC sensor.

• I forgot to take pictures of this but it's pretty straight forward. This video covers it well: https://www.youtube.com/watch?v=lPXMz1WTh-U
• I found that you do not need to remove the door sill trim. You can just pull the carpet out from under it and then stuff it back in.
• Also, removing that styrofoam thing makes accessing the lower two sensor bolts much easier.
• Since your harness should already be running to the correct spots, you can just plug the thing in once it's installed.

If everything works once you code the car, then wiring work is complete!

[heinzboehmer]

Coding/Calibrating

NCS:

This is the most straight forward part of the entire project. The process is essentially the same as coding the car for M track mode, with one extra step.

I followed this guide: https://www.ecuworx.co.uk/uploads/M-Track.pdf. Only difference was that I changed out my model year for a later one. I deleted the one that was there and added #0902. I'm pretty sure the value used doesn't matter as long as it's late enough. Did this right after step 11.

I'll quickly copy the steps over just in case that link ever changes/goes down.

1. Start NCS Expert
2. Load your coding profile (File -> Load Profile -> <profile>)
3. Hit “VIN/ZCS/FA”
4. Press “ZCS/FA f. ECU”
5. Select E46 in the box that pops up
6. Now there will be a list of 4 modules to read the VO from – pick either AKMB or ALSZ, doesn’t matter which
7. After a couple seconds, you should see the “FG” and “FA” fields populate.
8. Hit Enter FA.
9. Click Okay past the chassis and VIN. Most of the VIN won’t match your real one, don’t worry about that.
10. Now you will have a box titled “Enter FA” with a bunch of codes listed. Under Attribute type in “$7MA” and click “add”.
11. Ensure that $7MA got added to the list, and then hit okay.
    1. Delete your original model year. Click on it and hit the "delete" key on your keyboard (fn + delete might also be the correct combination for you)
    2. Under Attribute type in “#0902” and click “add”.
12. Click “back”.
13. Click “Process ECU” and then select “ALSZ”
14. Click “job” and change the job type to “FA_WRITE”
15. Hit “Execute Job”
16. Click “Change ECU” and pick “AKMB”
17. Make sure “JOBNAME” is still “FA_WRITE” and hit “execute job”
18. Change the job type to “SG_CODIEREN” and hit execute job again
19. Click "Change ECU” and pick “MK60”
20. Make sure the job is still “SG_CODIEREN” and hit execute job

If you happened to have retrofitted the ZCP brakes and steering rack, have a functional M-track mode symbol, and your car is a coupe, you’re done (with NCS)! Otherwise, go on:

1. Hit “Process ECU” and pick the MK60 module
2. Click “READ ECU”
3. Browse to C:\NCSEXPER\WORK
4. Look for FSW_PSW.TRC and open it in notepad
5. Apply whichever of the following changes are appropriate for your car:
   1. If you have non-ZCP brakes, look for “DRUCKMODELL_HINTERACHSE” and set it to “typ_2”
   2. If you have the non-ZCP steering rack, look for “LENKWINKELKENNLINIE_2” and set it to “wert_05”
   3. If you have a convertible, set “BAUART_MK60” to “cabrio_m”
   4. If you don’t have a functional M-track symbol, and don’t want to solder the LED, set “DTC_LAMPE” to “nicht_aktiv”. This will make the DSC system act like the non-M DSC where a single press makes the DSC symbol light up, and a long press makes the DSC and Brake lights turn on.
   5. Note: You can also do all of these changes with NCS Dummy
6. Save the file as “FSW_PSW.MAN”
7. Change the job to “SG_CODIEREN”
8. Execute Job

INPA:

1. Open INPA and click on the correct sequence of buttons to get you to the MK60 page. Found this video which shows how to do it step by step: https://www.youtube.com/watch?v=lseY6SRXWks
2. Go to "compensation routines"
3. Run all three and make sure to follow the instructions on them. Keep your steering wheel completely straight, do not touch the brake pedal and make sure your car is on a flat surface.
4. Go back and clear codes for any modules that have them
5. Cycle the ignition and check for codes again
6. If none are back, then you're done!

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Conclusion

And that is how you swap an MK20 module for an MK60 module. Hopefully this is helpful to someone!

Also, I added some driving impressions to post 55. Subjective, but thought the swap made enough of a difference that I would write about it real quick.

[DoubleSidedTape]

I had planned to do this and bought the full set of parts from a part out, and then decided to go with option 1 of buy a different m3. Pretty happy I did that.

[WestBankM4]

I had planned to do this and bought the full set of parts from a part out, and then decided to go with option 1 of buy a different m3. Pretty happy I did that.

Where's the fun in that? I'm just super thankful my 10/2002 build made the cut for the MK60.

[DoubleSidedTape]

Where's the fun in that? I'm just super thankful my 10/2002 build made the cut for the MK60.

I also got some nice pretty blue paint and 100k fewer miles.

[heinzboehmer]

I had planned to do this and bought the full set of parts from a part out, and then decided to go with option 1 of buy a different m3. Pretty happy I did that.

That was probably a good choice! I don't think I would ever do this again. I'm buying MK60 only cars from now on, but glad to have the module on mine now.

[bigjae46]

Awesome work!

[bmwfnatic]

Impressive, I'm not really interested in the MK20 > MK60 part of this, since I have a MK60 car.

But I do however have all the brake lines and clippings on stock because I plan to replace them all (rust).

What did you do about the one bend that the longer lines have to fit inside the shipping box, did you straighten that out somehow?

[heinzboehmer]

Impressive, I'm not really interested in the MK20 > MK60 part of this, since I have a MK60 car.

But I do however have all the brake lines and clippings on stock because I plan to replace them all (rust).

What did you do about the one bend that the longer lines have to fit inside the shipping box, did you straighten that out somehow?

I straightened that out with my hands. If it's a smooth bend and you don't see a kink, then the line will be fine. If you want it to be perfectly straight, you can buy a tubing straightener, but I didn't bother.

I watched this video a few times before starting on mine because I had never bent lines before. Great info and also hilarious: https://www.youtube.com/watch?v=_Tm6N5l69_c

[Obioban]

Wow, that looks like a BUNCH of work. Congrats, and thanks for the DIY!

... and to think I found going from 818.3 MK60 to 817.3 MK60 moderately annoying of a process

[George Hill]

You are a better man than me, I probably would have swapped the body harness lol. Nice work and I love the creativity.

[oceansize]

I feel like if you ask OP what time it is you will receive an enjoyable lecture on how to build a watch....

[CrookedCommie]

Awesome work! We discussed this in the track subforum, but if you are looking into doing this for a track/race car, worth looking into a mk20->mk60 Continental motorsport abs kit from https://www.rhtmotorsport.com/

I am in the process of doing this and will report back.

[thegenius46m]

Awesome work op!

Some advice for those attempting this that are realoem savvy... post 9/02+ non-m e46s are very similar hardware wise to the M3 and if you are not planning on buying new hardlines and other misc pieces you will save a lot of time grabbing the hard lines from a junkyard car if you can find one in good shape. i just checked and the hardlines are indeed identical for non-m and M3 MK60 cars so if you're swapping lines I would either buy brand new from bmw or grab good condition ones from an Mk60 non-m car for cheap along with anything else while you're in there because the parts are cheap.