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Old 08-20-2013, 03:09 AM   #1
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Join Date: Aug 2009
Location: gross deutsches reich USA
Posts: 963
My Ride: 323i with S54
E46 engine M54B30 swap into 1986 e30

What 24v engine is the best one for a swap into E30? When you put down all of the options on a paper and you average everything out, the M54B30 is what tops the list. Reason:

1: weights similar to M20
2: it makes similar power as S52
3: it has superior linear torque curve
4: The cost? they are cheaper than S52 now
5: plenty of them now to find at salvage yards
6: easy fit, similar effort as M50 to fit one.
7: electronics and wiring, easy now that I figured out the MS43, I offer stand alone plug and play MS43 for the swap
8: looks clean and modern inside the E30 bay

Here is how I swapped M54B30(or M54B25) into 1986 E30, I will only cover information that is different than M50 installation.

M54b30 is a great engine, its not all about peak power. This engine is nice and smooth running with original MS43 engine management. They are made from 2001 to 2006. The 2003 to 2006 come with different engine management MS45.1, I am working on that system next, but for now this information is for MS43 only, but long blocks and intake manifold is the same on both systems.
Best is to get M54 from 2001/2002 530i or X5, they will be less abused and engine harness will be long enough for the DME to fit above the glove box in E30. If you get one from 330ci/I then you will have to get engine harness from 5 series. I was able to get one from 2001 X5, complete for cheap but it had a missing DISA valve, that is expensive and you want to get one with good DISA valve and alternator.

#1 Oil pan. E34 oil pan fits, same as M50 on that. The M50 oil pump does not fit. You must use your M54 oil pan then mod the M54 pickup tube. I prefer the 1995 E34 oil pan, the baffle is separate, you will have to use the M54 oil baffle then brake off the oil pickup tube mounts. If you get older E34 oil pan, you will have to remove the integrated oil baffle. M54 oil pickup tube is easy to mod, cut the tube right where it comes out the oil pump just to give you enough room for weld, then cut the tube right before it starts making a bend towards snorkel, remove the tube when cutting, then clean it, install then make measurements so that the snorkel fits properly inside the E34 oil pan.

#2 Oil pan dipstick tube. E34 dipstick with added nipple that you will have to remove from your M54 dipstick, then make a proper measurement then weld it. It is a drain for the oil separator. Similar procedure is done for S52 OBD2 swap.

#3 Fuel pressure regulator and filter. On M54 fuel filter has integrated fuel pressure regulator. Charcoal canister will have to be moved. I moved mine where ABS pump sat, but I don't have ABS so you will have to find room for it. The the vacuum hose from the oil separator goes to pressure regulator. And fuel line from the fuel filter goes to fuel rail. It is quick connect but you don't need that, you can force the 8mm pressure fuel hose on to the rail line then above the notch put a clamp. Fuel filter can be secured with a bmw thin hose clamp, just loops around.

#4 Heater lines. There is only one heater line in the back of the M54 engine, the other line comes from a T on the E46 radiator. You would have to make to install a T and then route it to the heater core. I did not use the heater option, I live in hot climate. I just plugged up the rear plastic heater line. You can use quick connect, just cut the clamp and remove the hose, then install what ever length you need to what ever radiator option you want to use. I am using 318i radiator with one inch trimmed E30 mechanical fan.

#5 Radiator hoses. Use gates 21900, then cut to fit. Use the quick connects from the E46 hoses, then cut the clamps and remove the E46 hose from them.

#6 Power steering tank. E46 location can be used, so that it fits on the oil filter housing, then run the lines down. You will have to buy some oil resistant hoses there, I don't use power steering, I manualised my E30 rack, and I am happy that I did. Steering feel is great, little stiff at stand still. I use thin 185 tires.

#7 Brake power booster. It barely does not clear. With E28 green mounts plus 5mm spacer, I had to move it 5mm or 1/4 inch. Then I cut the brake pedal lip then rewarded it for the booster rod to have correct angle. Or just use E21 booster, it will have plenty of clearance. Right now I got about 1/4 inch.

#8 Exhaust manifolds. You won't be able to use M54 manifolds, even if you could, they are very restrictive. Use 96-99 M52/S52 tubular manifolds, some euro models came with these on their M54. I would not recommend any china headers on M54, that is because M54 lacks all of the studs.

#9 Intake hoses. 330i hoses will work. Don't use 530I/X5 hoses they have less of an angle and won't clear the brake master.

#10 Coolant temperature sensor for the gauge. It will fit in the block drain plug, but aftermarket sensor with shorter sensing element has to be used and use two washers. Original one is too long.

#11 Electronic accelerator pedal. Very simple install. The mounting bracket will not fit properly. I did not want to remove the carpet to make proper modifications so that mounting bracket just snaps on. But that can be done if you were to remove the carpet for cleaning. The upper mounting on E30 where pedal stop is located will have to be moved up half of an inch then rewelded. The bottom part will just have to be cut to shape. But I kept the carpet so installed the top part with a bolt, then bottom part of the bracket down in the carpet, then I drilled a small hole and installed sheet metal screw to secure the bracket, then trimmed some of the plastic from the pedal to clear the sheet metal screw head when slid on there. You must be careful with the bracket it can crack easy and they cost about $12. You can use any E46 gas pedal, mine is actually a pedal from Mini.

#12 Engine harness and engine management(MS43) installation and wiring. It all fits and routs fine. I used E30 harness bracket to mount M54 harness loom on the blower motor cover. Then the relays and DME can fit inside above glove box. I decided to install the relays outside then just the DME inside for proper fit. I will post more detailed information about the wiring later. But it is very simple. I coded the MS43 DME so that none of the emissions component are required, no EWS. Basically the MS43 works same as OBD1 DME. With minimal wiring it works great. I am also working on MS45.1. This was the only obstacle for people to start using these great engine in their E30.

#13. Engine installation. Install the long block first, then the harness, then the intake manifold, then install the nut that secures the manifold to the block, then install the throttle body. There is no need to remove brake booster, it can stay there.

#14. A/C compressor from same engine can be used, E46 compressor is better than E36, it creates great pressure with less load on the engine. No need to wire anything special, just use the E30 original compressor trigger wire. MS43 dme is so good that it detects the extra load on the engine and quickly adjusts the idle. Custom adaptors must be made from E46 ac lines to E30 as you can see in my photo it is home made.

#15 Wiring harness. You will be only working with wire section that have 02 sensor plugs on it like you see in the photo. Simply remove the automatic transmission wiring from that harness, it has blue plug. Main ground wire is brown in color and it goes to chassis, it will have black sleeve on it. Direct 12 volt wires are 4 red wires that are in pairs on a black plug, simply strip them and install banjo connector and install them on 12+ from battery. The 12 pin black plug goes to main engine harness and 12 pin clear plug goes to chassis, that's where the starter and alternator wiring is at. I will cover the specific wiring in another thread.

Photo of the harness that you will be working with the most:

To be continued...
Siemens MS43 tuning master

Last edited by HakenTT; 11-17-2014 at 07:43 PM.
HakenTT is offline   Reply With Quote
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