M54 E30 Swap
Oil Pan:
You're going to want to use the typical E34 M50 oil pan, with dipstick. Unlike E36 M/S5x swaps however you are NOT able to use the E34 pickup tube. The M54 oil pump is shaped differently and simply won't allow for it. The E36 oil pump doesn't fit the M54 block either so no sense trying that.
What you can do is modify the original M54 pickup tube to suit the E34 M50 oil pan sump.
What I did was make a jig bolted to the side of the block to give me a reference point as to where the oil pan was located. Before discarding the E46 oil pan I used a hole saw to cut through the sump to check physical clearance between the sump floor and the pickup tube. I found it to be just under 1/4" so I wanted to model that.
You want to cut and section the M54 pickup tube until you have the general shape you want, then tack/weld it into a finished unit. I tack welded it and then brought it to a friend to have it finished with a TIG.
E34 M50 pans come in 2 types, one with the windage tray build into the pan, and one without. Ideally here you should use the one without and retain the better one bolted to the block of the M54. No worries if you have one with, just drill out the rivets holding it to the pan and remove it. You cannot use both.
Now, that said there is also the option of ordering a European spec part from a E38 728i, which used a front sump oil pan like the E34's. The problem with this is that the part number(s) are not mastered in the US Dealer system and are then thus blocked. You would need to order them through a third party.
The sump tube for engines produced through 1/00 is P/N 11411432735.
The sump tube for engines produced from 1/00 is P/N 11417503261, with replacement windage tray 11137502669 (you can also lightly modify your existing windage tray)
If you order one or the other make sure you order the one that is correct for your engine oil pump, as they are not the same and will not interchange.
Engine Mounts:
You're going to want to use the same tried and true parts we use for E36 M/S5x swaps here, being E36 6cyl engine mount arms, and E28 M5 engine mounts.
11811141137 LEFT
11811138249 RIGHT
11811132793 2x
You'll want to trim the lengthy stud on the green engine mounts, and mount them to the outer hole in the subframe. The engine mount arms bolt right up the M54 in the locations you would expect.
Brake Booster:
There are probably a number of suitable brake boosters that can be used. I decided on a Porsche 944 booster because I had one on hand and I knew it would fit. The Porsche 911 from the same vintage also works, as do the E21 and 2002 units but they all have less power assist with their smaller sizes.
I did try to make the E32 735i / E30 iX booster work. The smaller diameter is great, but the front section still touches the manifold.
On the Porsche 944 booster you will need to cut the input rod to the correct length, and neck down the rod to the correct thread size to use the E30 U nut.
Power Steering:
You can use the LF20 or LF30 pumps that come on M54 cars. The LF30 is a better more reliable pump. They mount the same to the oil filter housing and should come with their own unique brackets. LF20 has a dome shaped rear housing, where as LF30 is a flat aluminum plate.
You'll need to fabricate the high pressure line that runs from the pump to the steering rack. I was not able to find anything factory that looked like it would work straight up.
Exhaust:
The typical eBay headers everyone uses for the E36 M/S5x conversions will work with modification, or you can use the E36 M52/S52 exhaust manifolds with the SAP ports plugged as is appropriate. Both have compromises requiring work to fit. You may also seek out European specification M52tu exhaust manifolds that look near identical to US E36/E39 M52 manifolds but without the machined ports for the SAP. These may be more of a hassle to source than its worth.
Years and years ago the eBay headers used to fit pretty well right out of the box, but it seems that quality control has slipped and now the down pipes are bent all sorts of wrong.
My solution to this problem was to cut the headers immediately after the collectors and weld on 2.25" vband assemblies, then fabricating a custom exhaust from that point on back.
The rear most bank of headers has an O2 sensor bung welded before the collector that will never work on a E30, it points straight at the firewall about an inch away. An additional bung will need to be added in a more amicable location.
Everyones taste and ideals is going to vary so much rearward of the headers/manifolds so just fabricate what you like.
M54 engines incorporate the SAP port into the cylinder head itself, with 6 tiny holes in each exhaust port to inject air into manifolds precat.
If you're not intending to retain the secondary air pump you'll want to order the factory delete plate.
SAP Blockoff plate 11121438086
Intake:
The M54 intake manifold is a serious piece of engineering, harnessing the engines natural harmonics, intake pulses and tuning them with a variable intake runner system BMW calls DISA. In conjunction with double VANOS this allows for a phenomenal torque curve, giving you a generous torque output across the entire RPM range.
As such in my opinion this engine is so much better suited to the swapper looking for a turn-key daily driver setup than the ever aging S52 option.
You'll want to use the E46 boots from the throttle body to the MAF to clear the brake master cylinder. You can fabricate your own air cleaner box, try to adapt a factory unit, or as I did.... Buy the pre-made product Castro Motorsport offers which is super nice.
Coolant Temperature Gauge:
There is no unused boss on the cylinder head to drill/tap like in the E36 M/S5x engines. There is a drain plug on the passenger side of the engine block that I've seen used for the gauge sensor but this poises two issues. 1. Its measuring block temperature, and 2. you have to space out the sensor with multiple washers as its too deep, hits a cylinder casing.
My solution was to use the upper coolant hose fitting from a E39 where it exits the thermostat housing, and tap it to fit the unaltered E30 coolant gauge sensor. Plastic of course is a poor conductor of ground so you'll need to affix a wire to the sensor and ground it. I drilled a small hole through the hex body and soldered it in place without too much fuss. The wire then runs through the same harness as the output wire and grounds to the oil filter housing.
Heater Hoses:
The lower hose that comes from the back of the plastic block pipe to the heater core is part of PN 17127548223. It is used in a slew of late model I6 BMW's like the E9x. All you need is the rubber portion, cutting the crimp rings at both ends to free it up. You'll need a straight oring adapter to hose clamp back on.
The upper heater core hose needs to tee into the lower plastic block hose and they both go to the expansion tank. It also comes from an E9x, PN 64216951946. It clips to the far end of the hose referenced just above. This hose has a good natural shape is droops into the appropriate position without tension and has a nice abrasion resistant cover on the portion that passes by the intake and booster.
Cooling System:
You can either use the late model E30 M20 radiator, or any E36 radiator. MZ3 will fit as well. Keep in mind the thickness and positioning of the core itself may determine if you are able to run a clutch fan or not.
I chose the E30 M20 because it fits a little better and I had a like new one laying around. I did trim the u channel cap across the top of the core just a bit to ensure the clutch fan would not touch. The fan and clutch are factory M20 E30 units, threads right on the M54 water pump and fits well. It leaves of a gap of 1/4-3/8" between the leading edge of the fan blade and the radiator core. Given its close proximity I do not feel a shroud is necessary or would even make a measurebale difference. E46/E39 are several inches apart as compared, thus necessitating a shroud.
I have tried numerous factory shrouds over the years on other 24v swaps and not found anything that "just works" It seems far too much work to fabricate something that would look decent when a difference would hardly be noticeable. E30's have much more frontal area catching fresh air anyway, not to mention significantly less restriction from other coolers sandwiched in front of the radiator.
For the upper and lower radiator hoses you'll have to get the quick disconnect fittings from donor hoses and use them with custom altered rubber sections clamped together. Cut the stainless bands off with a cutoff wheel, size the hoses accordingly then refit with normal hose clamps.
Upper radiator hose I used is a shortened E39 525i/528i/530i hose.
Lower radiator hose I cannot honestly remember what is as I tried so many combinations looking for something that fit well. It works but I'm still not happy with it. I will report back if I find something better. It is molded to an odd shape to clear the AC compressor and VANOS unit, and the E39/E46 hose is simply too long/wide to use.
Air Conditioning:
The condenser you should use is a Nissens PN 94172, the only one they offer for E30's. Pictures may show an older style but what you get the is parallel flow unit ideal for R134a. You may use your stock evaporator, but change the expansion valve to a R134a one.
The E46 compressor is a variable displacement unit and it is both efficient and lower drag on the engine.
You'll need both compressor line fittings from a donor to graft into the factory lines. I cut and brazed mine together before sending them off for fresh yellow zinc plating. You may also find a local AC shop to crimp the lines for you.
This is generally the same as E36 M/S5x swaps, although different parts.
Cut the E30 compressor connector off and splice the E46/E39 type on. Plug in and go....
Fuel Supply:
The M54 family of engines expect to run with a fuel pressure of 3.5bar. The factory E30 fuel pump can easily handle this task. You'll need to fit a regulator however. On a native M54 car the fuel pressure regulator is part of the long fuel filter assembly. There really is no good place to put this unit on an E30. It will not fit in the rear where the factory E30 fuel filter goes, and it looks awful strapped to the frame rail in the engine bay.
My solution was the use the factory E30 fuel filter, and insert the S54 fuel pressure regulator apparatus inline at the frame rail. This mounts to but unscrews from the S54 fuel filter. You'll need to remove and discard the S54 5bar regulator, and install the MS43 3.5bar regulator pulled from the fuel filter.
Then you need only connect a vacuum line to the FPR from the F connector on the intake boot, and use a factory quick disconnect fuel hose from the FPR to the non return fuel rail. Fuel input and return are handled neatly at the frame rail.
EDK Throttle By Wire:
As you probably know the M54 engines do not have a throttle cable. They are 100% drive by wire. There are hall sensors in the accelerator pedal that translate pedal movements into torque requests then sent to the EDK throttle body.
You're going to want to use the pedal, bracket and wiring from a manual car. You *can* use the one from an automatic but WOT is inhibited by a built in kick down detent and it is annoying. The wiring connector and bracket are keyed to the pedal (AT/MT) they are supposed to fit to prevent a mechanic from replacing the pedal with the wrong type.
You can get a pedal from just about any late model BMW that uses this system, E46, E38, E39, E53, etc etc.
Wiring is covered in the wiring section.
To use the electric throttle pedal you'll need to make some changes to the E30 pedal brackets welded to the floor pan.
Do what you need to do to get the carpet out of the way.The pedal stop bracket will need to have the spot welds drilled out, and then be moved to accommodate the geometry of the electric pedal bracket. You can weld it into its new position, use bodyshop panel bonding adhesive, or rivets if you like. It needs to be moved up about 1/2" or so. Use the MS43 electric pedal bracket to help you decide where to set it.
Make sure to plug the square hole in the firewall left by the throttle cable with something to prevent water intrusion.
As original:
As altered:
Finished:
Transmission:
You can use any of the typical E36 /S5x swap transmissions with the M54 engine. The bellhousing bolt pattern is the same. Just make sure to use the flywheel/clutch setup that matches the transmission.
I went with the ZF GS6-37BZ 6spd box from a E46 ZHP/Z4/E60 530i with the factory twin mass flywheel and LUK self adjusting clutch kit.
The ZF 320z from a E36 328i/M3 is most likely the easiest and cheapest route.
Driveshaft:
Driveshafts used will vary widely depending on transmission used. For my swap I used the rear half from a E36 M3, the front half from a Z4 3.0i, and the CSB from an E30. Length was as if the factory designed it.
Wiring:
You should start with a E39 or E53 engine harness. If your engine came from a Z3 or a E46 you really don't want to use this harness as the ebox is on the drivers side behind the strut tower on those cars. On the E39/E53 it is on the passenger side, leaving you ample room to mount the ECU in the factory location for the E30, above the glovebox.
X6011 is a translucent white 12 pin connector block found in the e-box of the donor vehicle, and is part of the main engine harness.
X6011 needs to have a wire run from pin 5 (which comes from starter connection 30h) to C101 pin 15. This will provide ground for the K5/K7 unloader relays and enable your power windows/sunroof to work. The starter backfeeds 30h with B+ during starter motor engagement to allow maximum amperage to the starter motor.
Since the MS43 harness will not have a 20pin diagnostic port you'll want to leave yourself some manner in which to reset the SI lights as they do their thing. Grounding C101 pin 11 then turning the key to accessory will reset the oil service LEDs, leaving it grounded a bit longer will reset the inspection. You can either leave yourself a pigtail under the M42/S14 firewall wiring covers to manually ground out, or you can wire up a diagnostic port exclusively for the use of resetting the SI lamps.
MS43 ECU controls the fuel pump relay by grounding terminal 85. Either construct your own fuel pump relay setup from the original E30 unit, or use a relay with pigtail removed from a native MS43 car. Wiring is as standard for a 5 pin BOSCH relay. The OE BMW relay is probably a lime green TYCO.
The primary engine harness requires no real modification and will be used as is. The secondary harness which connects to the chassis, automatic transmission and the rear O2 sensors will be heavily pruned.
MS43 harness as removed from an automatic E39 530i:
Automatic wiring and other extra crap removed:
What you're left with:
Labeling the C101 while I was figuring out both sides of the wiring:
I also elected to use my engines original MS45 valve cover with the pencil coils. This requires you to repin the X60005 MS45 ECU connector into the correct wiring for the MS43 ECU. The engine will NOT start if you do not repin, and may even damage the ECU. The power connector on the MS45 coil harness will need to be changed as well so get that from your donor too.
There is also a pencil coil type harness for MS43 cars that will work without modification if it is from a late run MS43 vehicle. The ETK seems inconclusive about this on the production dates, so I would advise you double check the pinout to make sure of what you have.
MS43 ECU:
There is a EWS Delete test file freely available from a user "Daniel F." He has a seriously informative Wiki page on his MS43 musings. Please refer to his page you can find the file(s) there.
Nothing really needs to be done to the ECU to start the engine and drive the car except having it flashed to remove the EWS protection. Without this the engine simply will not start. It will have a slew of faults stored in short order for communication errors with its buddies it expects to talk to on CAN, but these will not affect drivability. They would set a MIL/CEL but since the output for that is also on CAN the E30 cluster CEL bulb is not going to turn on....
These are the codes you can expect (perhaps more) with just the basic EWS delete Daniel F flash.:
This may present a problem to guys in California for example, but it's a non issue for some of us.
Additionally without modification of the ECU code the lack of a Vehicle Speed Signal will put the engine into a limited performance mode, dropping the fuel cut to 5500rpm or so.
Mark D'Sylva and Markert Motor Works both offer ready made tunes for the ECU intended for use on non-CAN chassis like an E30 to get you everything you need and none of what you don't.
Now, if you want to get your MIL/CEL working you're going to need some method of capturing the binary identifier for the MIL trigger. Garry Peterson "gpeterson" on here sells just such a device tailor made for this purpose. It is $250 and can be programmed to your specific desires, as it has additional features as well. It allows for ECU CAN control of a PWM aux fan like found on M54 cars via the factory temperature sensor in the lower radiator hose. It also tells the ECU when the A/C is on to raise the idle, and allows for ECU control of the A/C compressor so the ECU is allowed to make the final decision on when the engage the compressor clutch so that it can switch it off during wide open throttle, engine temperature too high, etc.
Finally it has one additional output that can be programmed to do any number of functions.
It looks like this:
You can use the M42 ECU bracket to mount the MS43 unit. It is not super tight but it secures it well enough.
Now what kind of performance can you realistically expect? Very very good! The M54b30 drives silky smooth, with ample torque available throughout the RPM range. Power with a good exhaust setup, tune is likely in the neighborhood of 250-265bhp.
Here is a video of my own car, driving starts about half way through and a 20-120mph pull is at the end.
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