swapping a m30b35 into a 525i m50

[rob101]

hello everyone,

I was wondering what the difficulty would be in swapping a 535i engine into a 525i 1992 I believe the manual transmission will be the same. Probably have to get new ecu and mounts but apart from that is there much to this swap? the other possibility would be an M52 swap.... but i'd expect the m30 would be more reliable, simplier to swap and more economical (don't have to run premium unleaded).

[liquidtiger720]

pointless. the m30 isnt any better than the m50 really, especially if you are going to put that much time and money doing a swap. you minus well do a s50 engine which would bolt right on. you'd just have to change the ecu afaik.

[kyleN20]

really, whats the point, you blow yer engine?

[rob101]

really, whats the point, you blow yer engine?
m50 W/O Vanos is a gutless wonder as well as not being very robust... no i haven't blown my engine but i don't know if i could be stuffed getting a rebuild on an M50........ that said i am only considering the options at this point. You don't know if you don't ask.

[pyro]

id do an s50 swap Thats what im hopeing to do this summer :)

[liquidtiger720]

m50 W/O Vanos is a gutless wonder as well as not being very robust... no i haven't blown my engine but i don't know if i could be stuffed getting a rebuild on an M50........ that said i am only considering the options at this point. You don't know if you don't ask.


gutless wonder?

tell that to Jon K. the m50 non t/u has more potential than the m50t/u. I'm wishing I had a non-tu right now so I can SC it.

why don't you do that? SC the bitch and be done.

[calmloki]

Well - from a while back - this is a really pretty swap + 5 speed conversion:

http://www.bimmer.info/forum/showthread.php?t=17371

[rob101]

what is the S50 out of? M3 or M5?

[Scott H]

it is possible, and relatively straightforward. I'll have a write-up soon. I didn't get as much done on the website during my plane rides as I thought.

You would need the engine (with wiring harness and ecu), tranny, and driveshaft.........

With M52/S52 you are getting in to OBDII and will have a harder time....this is why people suggest the S50 from a 1995 M3.

There's always more to a project like this than you think.


hello everyone,

I was wondering what the difficulty would be in swapping a 535i engine into a 525i 1992 I believe the manual transmission will be the same. Probably have to get new ecu and mounts but apart from that is there much to this swap? the other possibility would be an M52 swap.... but i'd expect the m30 would be more reliable, simplier to swap and more economical (don't have to run premium unleaded).

[winfred]

in the us the 95 m3 was the only year of the s50, only slightly more work to do a s52 (which came in all of the later cars, not sure where you are but there may be more options) and just use your intake and wind up with more power, you'd be using your harness anyway just drill and tap for the 2nd temp sensor in the head, the boss is there. a m30 won't work with the m50 tranny as it's a different pattern, a m3 motor would be easyer as all you need is the longblock and you put all of your brackets/accessorys/manifolds on it


what is the S50 out of? M3 or M5?

[Brandon J]

what is the S50 out of? M3 or M5?

Since you are out of Australia, the US S50 is a '95 US M3 engine. It is a tuned version of the M50tu with 3.0L and 240HP. You probably received the S50s with the multi-throttle bodies.

[winfred]

yea but you can't use the e36/39 harness or brackets anyway, with a iron block 52 motor theres one coolent sensor in the head so you need to drill/tap for the 2nd sensor that the early car uses, the other differece is the 52 motors run a crank position sensor in the block by the starter running on the tone ring on the crank between the counterweights, all of the ones i've seen still have the mount on the front timing cover for the older set up buy if it's not there you just use your old timing cover with it's mount, helped a buddy do a m52 in his e30 and it didn't run right till we noticed the ballencer that came on the m52 had the wrong number of teeth (god knows why as it didn't have a sensor reading on it in the 528 it came from) for the e36 m50 harness we used


With M52/S52 you are getting in to OBDII and will have a harder time....this is why people suggest the S50 from a 1995 M3.

[rob101]

in the us the 95 m3 was the only year of the s50, only slightly more work to do a s52 (which came in all of the later cars, not sure where you are but there may be more options) and just use your intake and wind up with more power, you'd be using your harness anyway just drill and tap for the 2nd temp sensor in the head, the boss is there. a m30 won't work with the m50 tranny as it's a different pattern, a m3 motor would be easyer as all you need is the longblock and you put all of your brackets/accessorys/manifolds on it
and a VANOS M50 ECU i don't have a vanos M50 :(

[winfred]

that could complicate matters :(


Since you are out of Australia, the US S50 is a '95 US M3 engine. It is a tuned version of the M50tu with 3.0L and 240HP. You probably received the S50s with the multi-throttle bodies.

[rob101]

that could complicate matters :(
not a problem take that manifold off and use M50 manifold QED.

from what i have read it does seem like a fairly straightforward swap to put a s50 in there, but i would have to change to a M50TU ECU wouldn't I?
Also wondering whether people could give me a roundabout figure for buying an S50 in australia?

[genphreak]

hello everyone,

I was wondering what the difficulty would be in swapping a 535i engine into a 525i 1992 I believe the manual transmission will be the same. Probably have to get new ecu and mounts but apart from that is there much to this swap? the other possibility would be an M52 swap.... but i'd expect the m30 would be more reliable, simplier to swap and more economical (don't have to run premium unleaded).Have you a garage? Why not buy a 540 from Japan (better be quick tho, legally this ends soon I think). Ship in, sell the parts off that you don't want, swap over the running gear with a rebuild in your own time, minimise new parts required, maximise time flexibility. The parts will help fund the swap, especially as you get to sell the old running gear too. :) Nick

[winfred]

i am not sure about the head on a euro m motor, i don't know if the ports are compatable with a m50 manifold, it may be possible to just use the multi throttle intake and mod a m50 525 harness to run it. yea vanos ecu and harness for manual or automatic tranny for whichever you have/want to convert to (atleast on a usa car)


not a problem take that manifold off and use M50 manifold QED.

from what i have read it does seem like a fairly straightforward swap to put a s50 in there, but i would have to change to a M50TU ECU wouldn't I?
Also wondering whether people could give me a roundabout figure for buying an S50 in australia?

[rob101]

i am not sure about the head on a euro m motor, i don't know if the ports are compatable with a m50 manifold, it may be possible to just use the multi throttle intake and mod a m50 525 harness to run it. yea vanos ecu and harness for manual or automatic tranny for whichever you have/want to convert to (atleast on a usa car)
What an Embarrassment of Riches with ideas on this forum lol, BUT i think i am partial to the Franken S52/S50 Idea its like the displacement of the M30 with the DOHC and VANOS of an M50. definitely on the cards me thinks perhaps i could import one from Japan as Genfreak suggested, Not too keen on going to V8 though (after all why not just buy a 540 V8) not too mention rego (jump through the flaming hoops) headaches

Hypothetically speaking i could source an S50 from the US it is not an impossibility in this day and age. god knows you'd probably get rorted anyway from the wreckers in this country... but i'll have to do break out excel and post on EUROCCA forums they should have an idea of the prices in aust.
My 525i is a manual which is why this swap makes alot more sense than getting an auto v8.

[Incantation]

if you're gonna swap make it a worthwhile one.. the m30 is a better engine, but .. you're not going to be gaining that much performance for the amount of money you're putting in