M50 Non vanos to M50tu swap requirements

[KingKalie]

Hoping someone can shed some light on this..
I'm curious to know what the requirements are to swap from a NV engine to a single vanos unit.

So take for example I have 1992 e36 325i non vanos non ews, but I would like to buy a new m50b25tu engine to swap in..

Will the vanos engine be able to run off the current harness and dme or would it require a whole new ecu and wiring harness?

I have searched other forums endlessly and all have different opnions on it some say you can swap the engine straight in and others say sensors are an issue for the non vanos ecu and harness

 

[Nikhil]

The engine itself bolts in directly. The ECU and harness between the nv and vanos are different. Personally I prefer the non vanos engine over the vanos engine.

 

[KingKalie]

The engine itself bolts in directly. The ECU and harness between the nv and vanos are different. Personally I prefer the non vanos engine over the vanos engine.

Yeah same.. but I'm having some issues with the current m50b25 and I feel the cost and time of repair is not worth it, seems an updated engine would be the cheaper easier and more hassle free option

 

[Nikhil]

The engine itself bolts in directly. The ECU and harness between the nv and vanos are different. Personally I prefer the non vanos engine over the vanos engine.

Yeah same.. but I'm having some issues with the current m50b25 and I feel the cost and time of repair is not worth it, seems an updated engine would be the cheaper easier and more hassle free option

well what issues are you having? an engine swap is probably going to cost just as much as fixing it thats without factoring in the condition of the replacement engine. these cars are really old now and theres no guarantee that you not going to endup with issues on the new engine in a few months tim.

 

[KingKalie]

Where do I even start..

The car sat for about 5 years without a head on the block, after the engine was reasembled I came across way too many problems that need to be fixed, it needs new injectors new coils new piston rings etc etc new everything, so if you take into considiration the cost of parts and labour I'm sure it would add up to more than that of a replacement from a reputable engine dealer no? what is the general cost of and overhaul for these m50's?

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And it pains me to say this but those 5 years not running were spent outside in the elements with no form of car cover or protection so believe me when i say time and nature took its toll on the engine and various other parts + it stood outside without a head on because a family member's girlfriend blew the headgasket on it and there was no space for it to be parked in a garage it's a sad story but the car is coming together beautifully with time, the only main issue is the engine

 

[Nikhil]

Ah ok that makes sense. Then I would look for a M50 / M52 bottom end and bolt your M50 head to it that way everything will be plug and play

 

[Ocky]

if you were thinking about changing to vanos, I’d go m52b28 rather than the 25.
Same work with changing ecu and loom and you get the extra capacity!
Decat and a chip and you’d be a happy man.
Plenty of b28’s floating around as well !

 

[KingKalie]

That sounds like a good idea, now the trouble is finding a sub assembly that checks out good :argh: I just thought a whole new engine would be easier because you can pick these 325i vanos motors up relatively cheap plus theres guys that bench test them for you so theres no doubt about buying a dud engine

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if you were thinking about changing to vanos, I’d go m52b28 rather than the 25.
Same work with changing ecu and loom and you get the extra capacity!
Decat and a chip and you’d be a happy man.
Plenty of b28’s floating around as well !

I have thought about this but I don't know, the 2.5 has always been close to my heart plus I'd be keeping it in spec with the car..