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View Full Version : E39 M52B28 to M54B30 Engine Swap Help



MrMuddle
10-15-2018, 11:24 AM
Hi All, wondering if anyone can help, I'm considering swapping in an M54B30 engine into my '96 E39 528i. My current M52 is dead so I need a new engine and single vanos 2.8's are getting more and more expensive here in the UK. So I'm considering moving to a M54 as they're more readily available and cheaper.

So my question was, what would I need to change to put an M54B30 in my E39? A few questions and thoughts so far...

1. Engine Mounts\Subframe - Is there any difference between them?
2. Does the M52B28 ZF gearbox bolt up to the M54 and do I need to change flywheel or clutch etc as well?
3. ECU wise my plan was to pick up an M54 engine harness and a stock M54B30 ecu with EWS delete.
4. What about ancillaries, starter, alternator, PS pump etc, are they all the same?
5. I believe the exhaust manifolds from an M52 bolt up to the M54?
6. Throttle Body\Cable - I believe you can buy an adapter from Turner which allows you to run the M52B28 tb on the M54B30 inlet, would the M54 ecu still work with the TPS output?

I guess my other question would be, with an ODB2 engine\ecu in an OBD1 car, will the dash and tacho etc still work or will it end up a very bad xmas tree with check engine light etc?!

Thanks very much
Rob

geargrinder
10-15-2018, 02:12 PM
Yeah.... Rob I think prob you might run into some coding work to be done? The super early E39's had a few special/different things on 'em that dropped off in the first year or two of production. I can't say with authority but I suspect you're correct about the modules needing work. I'm sure it could be done but it probably will be tricky and you might be delving into "only guy who's asked the question" territory with such an early car... We almost NEVER see '96 E39's and they seem to always turn up to have some weirdo things about them...

Most of the bolt-ons will work I think based on my experience being involved in sticking a M52TU28 block into an M54 325 while keeping the M54 systems onboard. Depending on where the M54 comes from you might need to swap the oil pan (ie. if its from an E46...) The M54's get a different exhaust manifold, I suspect larger/better, but you'd have to confirm. The existing one should bolt up tho' based on what I recall.

To be honest I think its probably a ton of work, and weighed against a slightly more expensive drop-in M52TU... for very little benefits and ton of uncertainties... I'd probably stick w the M52. Surprised they are that much more $$ than the M54's... I don't think that's remotely the case here (thats' how project above came about cuz my bud was able to get a running / driving wreck 328 for next to nothing vs what an M54 motor would have been...)

ross1
10-15-2018, 02:24 PM
Externally these engines are pretty much same so it'll go in no trouble. With the M54 harness and non EWS DME I'd think you are essentially plug and play. Perhaps some coding as stated.
I feel the M54b30 is a VAST improvement over the M52 single vanos

MrMuddle
10-16-2018, 05:42 AM
Thanks very much both, that's very helpful. I was hopeful mechanically they'd be the same. Mine is the single vanos M52B28, so a B28TU would I guess still need some, if not the same amount of work as an M54.

In some instances a single vanos engine is double the price of a TU or M54 as everyone has used them for drift cars as they were easier to replace 1.6 and 1.8's etc than a TU or M54. I'm also thinking if I swap over to an M54, as they're much easier to find, if I kill this engine at least it will be easier to find a replacement.
My E39 is boosted so I want something I can easily and cheaply replace in case I kill another engine! :)
UK ones are all the ally blocks and finding an old cast M50 is even harder and more expensive!

geargrinder
10-16-2018, 08:37 AM
Interesting explanation on the depletion of MS52TU blocks. Well... Wait a minute... If your M52 is boosted be sure your gonna be able to retune it on MS43. It's a very different beast. On our side of the pond there's very very few boosted M54s. That's for 2 reasons - alloy blocks and less well known tuning. I guess you're already on alu block but be sure you got the tUning sorted too I guess.

djb2
10-16-2018, 10:02 AM
Don't forget that the M54 is throttle-by-wire. The throttle pedal is very different, and the wiring harness will need to be added. It's not a matter of an adapter to physically use the M52 throttle body, the ECU needs to control the throttle plate not just read the pedal position.

geargrinder
10-16-2018, 05:36 PM
Right the adapter is really so M54s can run cable throttle for standalones I think, right?

MrMuddle
10-16-2018, 06:00 PM
Thanks everyone, really helpful. Sorry I should have mentioned I'm also running Megasquirt 2. On My M52 setup I just left the stock ecu in place to control vanos and the cluster/tacho/EWS. I know MS2 can run vanos via an output as well as the tacho out, but I figured it was just easier to let the stock ecu do it, and probably better tbh! I was considering tuning the M54 ecu with something like TunerPro, but from what I've read up on so far I think you need to buy a flash module or replace the flash chips each time to be able to update the tune, not sure if that's correct or not?

The only reason I was considering keeping the M54 ecu if I did the M54 swap was to control the dual vanos. So the cable M52 tb would stay the same, but I guess it would depend on if the vanos uses TPS as an input for vanos adjustment or not? The other thing I was wondering was how the TPS 5Vref and Signal works on the M54 TPS, does the fly by wire pedal control the tb but still output to the ecu, or does the fly by wire pedal communicate with the ecu and the ecu controls the tb?

Worst case I guess I could sell my MS2 and look at getting an MS3 to control everything, but I'd rather stick with the MS2 if I can to save money.

It's definitely sounding positive though, sounds like the engine should drop in, I'll check on all the ancillaries and then it's just the electrical side and dash to figure out.

geargrinder
10-16-2018, 06:49 PM
LOL dude that's a pretty massive "oh and I forgot to mention"!

Absolutely not re chips, for MS43 you can absolutely flash the thing over and over again with a cable... no primitive chipwork required.

Whether the MS43 will live happily w the MegaSquizz and no throttle control I don't know... BUT I'm not optimistic. Typically the DBW ECUs get freaked and lockup in failsafe mode if tbey don't see their DBW throttle commands being executed as requested.

BimmerBreaker
10-16-2018, 10:10 PM
Right the adapter is really so M54s can run cable throttle for standalones I think, right?

Yes and the adapter also lets you use M54 manifolds on M52TU's

MrMuddle
10-17-2018, 04:23 AM
lol sorry, I should have mentioned it earlier. Still, I still needed to know about the swap in general though and whether it would work.

That's very interesting on the MS43 ecu, I'll have to do some more reading on it then as maybe that's another option, ditch the MS ecu, get the fly by wire pedal gubbinz and look at tuning the MS43 ecu instead.

Do you know if the electronic accelerator pedal connects directly to the ecu via it's own loom or is there lots more loom etc under the dash? Just looking online and I could pick up a used pedal for about £20, but it's what else I'd need to go with it. I know MS2 doesn't do fly by wire but can probably work around it!
I guess I'd need the stock ecu to control the DISA too!

GG///M3
10-17-2018, 09:30 AM
I’d stick with that single vanos motor

Ricardo999
05-17-2020, 07:50 PM
Hello ..
You do This swap?
Thanks mate

Smoky540i
01-25-2021, 05:13 PM
I wonder if anyone has actually completed an M54B30 swap into an early 528i....?


Hello ..
You do This swap?
Thanks mate

crdiscoverer
01-25-2021, 07:32 PM
I wonder if anyone has actually completed an M54B30 swap into an early 528i....?

Not worth it. I have an early 528i with a single VANOS M52 as well and I've explored this swap in the past. Mechanically, the earlier I6 E39s almost have more in common with E36s than with other E39s. Going from an M52TU to an M54 is stupid easy in comparison.
One of the reasons I went with forced induction instead.

I also suppose single VANOS M52B28 engines are scarce because that's the most powerful non-M engine you can simply drop-in into lesser E36s.

If anyone is considering this swap, focus on the E36 sub-forums as it's not an uncommon swap for them. Here is one good starter guide https://www.ascfabrics.com/m54e36
I wouldn't attempt this swap without a full M54 donor car sitting right next to me.