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E36 LS Swap - ABS Relocation Kit instructions

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  • E36 LS Swap - ABS Relocation Kit instructions

    If you are reading this you are looking at doing an LSx V8 engine swap in the BMW E36 chassis, which was made from 1992-1999. As part of the swap to install a V8 engine into the engine bay of the E36 - which only ever came with inline 4 and 6 cylinder engines from the factory - the ABS system has to be relocated. The ABS "pump" is right where the exhaust headers have to go, so we make a number of parts to facilitate this relocation. We are using this forum thread as the Instructions for installation of these parts.

    We are asked these questions all the time, and here are the answers:

    1. Do you have to relocate the ABS pump with an E36 V8 swap?
    A: If you want to use full length headers, then the answer is YES.

    2. Do you HAVE to keep the ABS system in the car?
    a: No, but if your car will ever need to stop or turn, you will want it!

    These E36 chassis BMWs had exceptionally good Anti Lock Brake Systems (ABS) for that era and we have found out - the hard way - that when you remove the factory ABS systems from these cars the front to rear brake bias goes right out the window... and they Just. Won't. Stop.

    This was me locking the rear brakes in our X PRepared BMW at the 2008 SCCA Solo Nationals held at Heartland Park Topeka. For years the factory 3-channel ABS had worked flawlessly in this V8 swapped E36, in both road course and autocross conditions - even with the 315mm wide Hoosier race tires! Yes, it can compensate for a lot of changes and still function beautifully. A properly functioning ABS will give the driver confidence to brake later and stop shorter - no human can control 4 brake calipers 100s of times a second with their foot and one pedal! But on the car above, the ABS unit stopped working. There was some serious rain during this week long event, and this car had no windows so the ABS module got wet - and fried the electronics.

    You won't know that the brakes are going to lock up with a failed ABS until you hit the brake pedal hard enough to engage the ABS. On my first timed run of that year's Solo Nationals, going into the first corner where I pressed the brakes hard (after the module got wet and fried), the rears locked badly. I fought with the brakes for the next 2 days but it just wouldn't stop worth a damn without the ABS functioning. Why?

    It seems that the automotive engineers who design brake systems stopped doing as much development with "regular" brakes after the invention of ABS, and they quit worrying so much about front to rear brake balance in the factory brake master cylinder. "Let the computer figure it out", they said, and the ABS system is used as a dynamic front-to-rear biasing tool.

    These are the two E36 BMWs I raced - and used for Vorshlag development - from 2004-2011

    And strangely enough, this early 1990's ABS from BMW works pretty dang well, even when we radically change the tire size, compound, and weight of the vehicle. I have years of racing in E36 BMWs, with both 3- and 4-channel ABS systems, in all sorts of conditions. I have found that it is VERY difficult for me to "overdrive" the BMW ABS system and cause it fault. Its happened twice in a dozen years of racing, and both times I was drifting sideways into some tight elements on an autocross course, braking at 100%, and going over a big bump. Freak occurrences and incredibly bad judgement - and only then did the factory BMW ABS start pulsating wildly and I lost ABS function.

    With the ABS out of commission, the rear brakes will lock violently and make an E36 want to spin into a corner. Not fun. Losing the ABS ruined my entire Solo Nationals in 2008 - which affected my entire year of racing - and I vowed to never run without ABS again. And thus spurred our ambition to offer an ABS relocation kit for the E36 chassis soon after we started producing the V8 swap kit in 2007...

    You can read more below about the specific parts we offer to help relocate the the early (3 channel) and late (4 channel) BMW E36 ABS systems.

    Last edited by Fair!; 01-18-2017, 01:07 PM.
    Terry Fair -
    2018 GT / S550 Dev + 2013 FR-S / 86 Dev + 2011 GT / S197 Dev + C4 Corvette Dev
    EVO X Dev + 2007 Z06 / C6 Dev + BMW E46 Dev + C5 Corvette Dev

  • #2
    Re: E36 LS Swap - ABS Relocation Kit instructions

    The factory ABS pump on a Left Hand Drive BMW E36 chassis is nestled under the master cylinder, as shown below.

    This is absolutely in the worst place possible for a "V8" engine arrangement. You see, the inline 4 and 6 cylinder engines BMW used on this chassis all had the HOT exhaust parts on the OTHER side of the engine bay (the right side, as viewed from the driver's position), with the relatively benign intake manifold and air tubing on the LEFT side. So putting the ABS pump there made since for the stock engine arrangements.

    The 3.2L "S52" inline 6 cylinder engine in a 1997 BMW M3 - with exhaust on the left from this angle

    I put the first LS1 V8 engine into a BMW chassis back in 2002, and we have learned a LOT of things since then with over 180 V8 swap kits built. Some folks who do their own "home brew" V8 swaps don't want to mess with the ABS pump relocation and do some pretty interesting things to make room for the exhaust. But the simple truth it, keeping it in the stock location is a bad idea even if you could make the exhaust around it without compromising the exhaust flow and performance - which you can't.

    The ABS pump is full of hydraulic brake fluid, and has solenoids that are actuated electronically. Having this next to an exhaust manifold or header is a bad idea in the long term - the heat from the exhaust being right next to the ABS pump is going to cook the unit and/or boil the brake fluid. Not good things to figure out on the street or a race track.


    Moving the pump to the front of the engine bay, away from the V8 engine and exhaust heat, is a smarter move. We started with the 3 channel units, which are used from 1992-1995 on both the non-M and M3 E36 chassis. The first item we developed was the 3-channel ABS relocation bracket, shown below.

    Many people just buy the bracket from us then make new brake lines, and we are perfectly happy to sell you just the bracket. It is much less costly than the brake line kit we sell. This bracket includes new BMW sourced bushings and hardware to attach it to the frame rail, as shown below.

    We keyed the laser cut and bent steel bracket to fit over a factory stud that is welded to the left front frame rail. This normally locates some bracket in the OEM air intake tubing, which is no longer needed on a V8 swap.

    Make sure when you are stripping the OEM engine out to NOT cut away this stud. We include a new BMW sourced plastic nut that is threaded for this particular stud. Install that to locate the bracket as shown above.

    With the bracket located and held in in place while, drill the two additional holes shown above.

    Once you have the holes drilled, attach the supplied bolts and nuts through the sheet metal in the holes shown above.

    Now you can install the 3 cups and rubber bushings, as shown above. The rear two bolt into holes and the front cup slides down into a slot and is then tightened. Now you have a bracket mounted and ready to accept the BMW 3-channel ABS pump assembly.

    To install the 3-channel ABS pump, slide the rear of unit into the two rear bushing cups at the back of the bracket. Now remove the 3rd bushing/cup and slide over the front stud of the ABS unit, then rotate the pump down and slide the cup into the slot shown above. Those 3 "bushing cups" are what hold the ABS pump in place, as well as isolate the unit from vibrations (and damp the vibrations from this pump to the chassis).

    That's how you located and install the 3-channel ABS relocation bracket and pump assembly. Read below to learn the 1996-1999 E36 4-channel pump bracket and mounting, which is different in many ways.
    Last edited by Fair!; 01-17-2017, 12:19 PM.
    Terry Fair -
    2018 GT / S550 Dev + 2013 FR-S / 86 Dev + 2011 GT / S197 Dev + C4 Corvette Dev
    EVO X Dev + 2007 Z06 / C6 Dev + BMW E46 Dev + C5 Corvette Dev


    • #3
      Re: E36 LS Swap - ABS Relocation Kit instructions


      The the 4-channel ABS unit is a different size (longer) and has to be located in a different place in the engine bay. The longer 4-channel relocation bracket we make would not fit in the same space that the smaller 3-channel ABS pump did.

      This unit has more brake line connections (4 channel vs 3) and the plumbing is a bit more cluttered. This bracket doesn't key off a stud, but once you lay out our brake line kit it becomes obvious where it needs to go.

      Unlike the 3 channel bracket the 4 channel unit (above) mounts farther forward and at an angle. This was needed to clear the longer ABS unit, to route the additional brake lines, and to clear the power steering pump (we build the E36 LS1 swap around 1998-2002 Camaro front drive accessories).

      Vorshlag's 4-channel ABS relocation bracket and lines on a 1996 BMW M3 LS1

      Let's take a look at the 4-channel brake line kit we make to help simplify the swap...


      We used to offer ABS brake line relocation kits, which included the hard and soft lines needed to relocate the ABS pump for the V8 swap. Due to costs and extreme hassles in shipping them we stopped selling these in 2018. Please use these images to get an idea of what you need to do to plumb your relocated ABS unit.

      Above are the two "main feed" lines that go from the brake master cylinder to the ABS unit. These are the front and rear channels from the MC, and they are routed as shown above. That's the 3-channel but the 4-channel lines are very similar.

      Here's another picture above of the two "main" lines from the MC to the ABS, with the "F"ront and "R"ear channels marked. Again, they only install one way, if you have our bracket mounted correctly.

      There are two low pressure "return" lines that go from the ABS pump to the brake reservoir, shown above. These black lines are special hydraulic fluid tolerant low pressure lines in two very specific sizes, and these are needed for both the 3- and 4-channel swaps. They just need small hose clamps at both ends, and they return excess brake fluid back to the main reservoir from the pump. In the image above these lines were secured to the strut tower with a "P" clamp bent into a rectangle (not supplied in the kit), but you can use whatever method you like to hold them up.

      Now for the fun part - the lines that go from the ABS pump to the 4 corners of the car.

      This first picture above shows where to cut for the "splice" to attach our included brake line(s) to the factory rear brake line(s) for the 3- or 4-channel kits.

      You can figure out where to put the splice, then flare the remaining OEM line to fit the included junction. This is the only line that has to be cut and flared. As you can see in the image above it is a 45? flare on a 3/16" line. NOTE: Make sure to install the fitting BEFORE you flare the hard line!

      The 4 channel E36 cars (1996-99) have 2 rear brake lines and the 3-channel E36 cars (1992-95) have just one rear line. There are more differences, but that's the main one.

      The image above shows the 3-channel ABS relocation brake hard line (that we used to sell) successfully spliced into the OEM rear brake line. This work is much easier to do with the engine out of the car and should be your first step in any LS1 swap into the E36 chassis.

      The 3-channel ABS unit is shown mounted and plumbed above. Please note the Right Front, Left Front, and Rear notations we added. The units are marked as such, in German, but this marked image should should be easier to comprehend. Due to space constraints to the power steering reservoir and pulley, two of the 3 junctions on our old 3-channel hard line kit used an banjo fitting, as shown.

      The 4-channel plumbing is more complex for the LF, RF, LR and RR lines. As you can see two of the ports have adapters - some of the ABS pump ports are bigger than others, but we would make them all use the same line size and fitting with adapters.

      Now all you have left is to plumb are the hard lines to the front brakes. Both the 3- and 4-channel kits we used to make had the lines routed through the sheet metal, as shown above. This is very different than the OEM routing. We did this to simplify the kit and make it much easier to ship - if we had routed them like the OEM lines the adapter lines would be much longer and even more expensive to make and ship. This re-routing "short cut" was necessary in order to keep the size of the two lines to the front wheels reasonable, but since you are making this yourself you can go whatever route you want.

      The OEM hard line to the RF caliper routes way back to the firewall and under the frame rail and all the way forward to the inner fender liner. The new line we made was much shorter and goes straight from the ABS pump, down along the crossmember, and then to a bulkhead connection above the frame rail - as shown above.

      This is another picture of the re-routed RF hard line from the 3-channel kit, which makes a bee line down to the crossmember and over to the right side sheet metal near the caliper.

      This image above shows what we're trying to do with this "short cut" - the line passes right through the inner fender liner and terminates into a bulkhead fitting and 90? adapter - fittings which we provide in these kits. This fitting is bolted to the chassis in a hole you drill, then the "flex line" connects here feeding pressure to the front caliper - as shown above. Its actually much easier to install than it is to explain in writing.

      The LF line is even shorter and goes from the ABS pump, to the bulkhead fitting you add to the inner fender, then to the flex line as shown. The OEM line goes waaaaay back to the firewall and around the inner fender, then back forward.

      The image above of the 4-channel ABS unit shows the very short hard line we supply to go to the Left Front corner, with the bulkhead connector drilled and installed.


      One thing we always recommend adding for any of these ABS relocation hard line jobs are heat shields, which might be necessary in your application.

      The image above shows a stainless steel heat shield we built for a 4-channel ABS E36 M3 we built for a customer. The relocated brake lines are near the long tube headers we sell, and these stainless steel shields and an air gap help keep exhaust heat away from the lines and fluid.

      This is the heat shield with the header removed, above. We do something similar on the right side of the engine bay - another SS heat shield - to keep wiring away from the header heat on that side.

      We never made a "plug-and-play" solution for extending the wiring harness that controls the ABS pump assembly.

      We just do this the hard way - cut the end off the chassis side harness, extend each wire at both ends, then it will reach the new ABS locations.

      You can get creative and route the extended harness behind the fender, if you want the harness hidden. Otherwise just run it around the strut tower and wrap it in harness sleeving.

      Its about 1 to 1.5 hours of work cutting, marking, extending, and soldering wires, but its not difficult work - just tedious.

      THAT'S IT!

      We hope this series of posts has been helpful to show WHY we need to relocate (and keep!) the ABS pumps in the E36 chassis for V8 swaps. The pictures should help you show HOW to install either the 3 or 4-channel ABS brackets, the hard lines, the soft return lines, and the bulkhead connections at each wheel.

      Again, we no longer sell the hard line kits and welcome anyone to create and splice in brake hard lines thelmselves, and these pictures should help you with routing options.

      Please feel free to use these images to save a few bucks and make your own brake hard lines. We still sell the ABS pump relocation bracket kits.

      Last edited by Fair!; 03-08-2022, 06:41 PM.
      Terry Fair -
      2018 GT / S550 Dev + 2013 FR-S / 86 Dev + 2011 GT / S197 Dev + C4 Corvette Dev
      EVO X Dev + 2007 Z06 / C6 Dev + BMW E46 Dev + C5 Corvette Dev


      • #4
        Update June 9, 2022: Couple of changes and updates to the ABS relocation mounting kits we make for the BMW E36 that need to be shared.

        In March of 2020 I wanted to see an update to these brackets. We used to make both the 3 and 4 channel brackets from the same CNC laser cut blanks, but it was less than perfect. Once we were operational with our in-house CNC plasma table we changed the design into two blanks, which have different features for the 3- and 4-channel designs, shown above and below.

        We can now make these more cost effectively AND with better features, and do so in larger batches so we shouldn't ever run out of these again. Our Laser cut supplier was getting really behind on orders and pricey, too.

        Next up - we had to cut out some parts in our assembly to hold prices in line. The ongoing supply chain issues / pandemic price gouging have really driven up some OEM parts costs to extreme levels. This has affected us in many ways - now we no longer sell any of our OEM based brake upgrade kits, due to wildly fluctuating prices and lack of availability from Ford, and now it has hit some of our BMW sourced parts.

        These rubber bushings (we use 3 to mount the ABS brick in our bracket) went from $2 to $17, almost overnight. So now we ask that E36 LS1 swappers salvage the OEM bushings from their donor chassis. Ditto the steel cups - there is ONE bolt-on cup on the E36 chassis and two that are welded on, so we cut our supplied amount in our kit from 3 down to 2 per kit (these went way up in price, too). We now supply what is shown in the two "kit pictures" above. If you want all new parts you can source them with the part numbers we have shared in the above left pic.

        We stopped offering the 3 and 4-channel brake hardline kits years ago, due to super high price jumps and difficulties in shipping these hard-to-package items. But we're still trying to source a wiring harness to make the electrical part easier. Stay tuned for more on that...

        Last edited by Fair!; 06-09-2022, 01:49 PM.
        Terry Fair -
        2018 GT / S550 Dev + 2013 FR-S / 86 Dev + 2011 GT / S197 Dev + C4 Corvette Dev
        EVO X Dev + 2007 Z06 / C6 Dev + BMW E46 Dev + C5 Corvette Dev