I made a post offering to help Nocones with an ABS install on his LMP360 project, and was quickly asked to make a post to help everyone on the forums with what I know about ABS and how to get it to work in a car it wasn't designed for, so here it is! I'll try to get everything I can think of into the first couple posts to keep all of the main information together, but I'm sure that I'll miss something. And feel free to ask questions if I wasn't clear on anything.
ABS is a scary thing to play around with for a lot of people. When it works, it's great. But when it doesn't work, it can be a real pucker moment, especially on high speeds on a racetrack. I think the scariest thing about it though is that it's a mysterious box that there is very little information on, and it's the thing between your brake pedal and the car actually stopping. That said, the MK60 (and its variants) are not as difficult to understand as one might imagine.
Teves (or Continental or ATE or whatever you know the manufacturer as) accidentally made the car hobbyists dream come true when they developed the MK60 ABS. In an automotive world where all of the electronics are so interconnected, they developed an ABS system that did not require any outside communication to it other than power (other than ABS/DSC specific signals which I'll talk about later). This is essential for us, because for many ABS systems, specific CAN messaging is required for the system to not go into a fault mode. That is not the case for the MK60. When running "standalone", the MK60 is perfectly happy and performs just as well as it did in the car it was designed for. Teves likely did this so that they could sell the unit to many different manufacturers without forcing those manufacturers into integrating the ABS, or having to design custom software for each vehicle that they installed it in.
So what is a MK60? The MK60 that most people know and love came in the 03-05 BMW M3s. There were a few different part numbers for those, but they are getting increasingly rare to find, and more expensive when you can. Most people use this model because it has software that makes it perform slightly better than the non-M3 variants, but there are non-M3 MK60s, and they still perform better than no ABS at all. They are also cheaper than the M3 units since they are less desirable. Prior to 03, these E46s came with another ABS variety called the MK20, which does not perform as well, and you probably don't want, so make sure you take a good look at what version you are getting. The MK20 and MK60 are visually different. They also use a different electrical connector. MK60s also came in other cars, like Minis and Volkwagen Automotive Group, but I haven't played with those, and don't know if their connector pinout is the same.
So first things first. How do you mechanically install an ABS system? Well its recommended that the ABS pump be rubber isolated so that it does not receive all of the vibrations in the car. This can damage electronics, as well as mess up the pump functioning properly. Stealing some pictures from Louis at GSpeed, since I am not around my car right now and he already had a writeup of his install on CorvetteForum (thanks Louis!) Note the orange rubber isolator that the pump is sitting on top of. You can use rubber isolators directly like this photo, or bolt the pump to a plate, and use the isolators to hold the plate up. Dealers choice.
Next, we have to hook up brake lines to the ABS pump. The markings on the pump are in German, so look at the pictures below for the translation to English (again, stolen from Louis ...). All of the ports on the pump are bubble flares (or DIN/ISO flares), and inverted (or double) flares (the norm on most cars these days) will not work. There are also 2 different threads on the ports. The two inputs (Front and Rear) are M12x1.0 thread. Two of the outputs are also M12x1.0 (Front Left and Rear Left), the other two are M10x1.0 (Front and Rear Right). I also recommend using 1/4" brake line from the master cylinder to the ABS pump, and 3/16" brake line from the pump to each wheel. If use smaller input lines, you may get weird results when ABS is applied as it can't source enough fluid from the reservoir effectively. One last note, you may have to get extra long tube nuts for the M10x1.0 ports. The ports are strangely deep, and some tube nuts will bottom out on the hex portion before the brake line seals in the bottom of the port.
Pressure sensors - There is some debate on whether the pressure sensors are required for a MK60. While they aren't required 100% for the MK60 to function, it will help reduce "ice mode", which is where the brake pedal is pressed, but the car doesn't want to slow down. There is a well known company that sells wiring harnesses that does not use pressure sensors or yaw sensors, and I have not personally heard of issues from that, but I like to be on the safe side when hurtling 120+mph into a corner. The pressure sensors need to be installed in the feed lines from the master cylinder to the ABS pump. One in the Front line, one in the rear line. These can be installed using some banjo adapters made by Atec, or you can install them using an adapter block that has 2 line ports and a pressure sensor port.
Yaw sensor - Again, there's some debate on whether this is needed, but I always err on the side of caution with brakes. The yaw sensor needs to be mounted with the mounting tabs up, and the connector towards the front of the car. See pictures below
Next, lets talk wheel speed sensors. The MK60 uses a 2 wire active wheel speed sensor. This means that old passive (variable reluctance or VR) sensors will not work with the MK60. You can recognize the VR sensors if you put a multimeter across the sensor in AC Voltage mode, spin the hub/wheel, and see voltage greater than 0VAC across the sensor. Again, this type will not work.
There are quite a few OEM sensors that are known to work with the MK60, but figuring it out is mostly trial and error. We can talk about testing if anyone has any questions about a certain sensor. I have heard OEM 370Z sensors work. I also know that '09+ C6 Corvette sensors plug in and work directly. There are many others, but I don't know them off the top of my head. Most people, if their OEM sensors (if their car came with sensors) don't work, use E46 M3 sensors. These sensors can be identified by the blue connector on them. The gray connector sensors that look the same will not work.
You will also need a reluctor wheel for most setups. The reluctor wheel can be pretty much any tooth count, as long as there is the same number of teeth for all 4 wheels.
When mounting the sensor, it must be VERY close to the reluctor wheel. I think the spec is generally around ~1mm away from the teeth, but make sure that the teeth will not contact the sensor. A tiny bit of variation of distance is not a problem, but when you start getting 2-3mm away, the sensor may stop picking up the signal.
Next up, wiring!