E46 engine swap

[Jim320i]

Looking for some info with regards to an e46 engine swap

Just picked up a 318i with a fooked engine in, but also have a 325i which is rough round the edges.

Anyone know if upgrading the 318 to the 2.5 is a straight swap or is the wiring different?

Brakes different? Diff I assume is different.

Alternatively I might trey and pick up a 1.8 engine and just swap that for a different one but already have the other good engine from the 325 sitting here.

It's something that would need to be done in 1 weekend so that's why I wanted to know if a simple engine swap would work

Any info will be helpful

[bss325i]

Not as straight forward as say converting an E30 from 318i to 325i.

There are also EWS/DME issues to overcome unless you swap everything over and then you would have a different ignition key to the lock barrels on the car unless you swapped them over and then if you ever needed to order a new key you would run into id dramas at BMW as you need proof.

It's not impossible but its a load of unnecessary agro for little gain.

Just but a replacement engine for the 318i.

N42 or M43?

[Jim320i]

It's the m43. It's an s reg. really tidy condition, just the engine is knocking really bad.

The missus has a 325i now which is ropey and covered in dents so if I can get the 318i sorted it would be a bit more presentable and probably a lot better on fuel.

Not looking for loads of work so if I can source a cheap engine or another 318i I can get it switched. In no rush as she can keep using the turd of the 2

[Jim320i]

Bring this back up while im thinking about it...

Would a M43B16 fit the E46? Engines look the same other than a few bits and pieces attached.

I picked up a E36 compact the other day with low mileage which might be ideal if I decide to fix the E46 up.

[bss325i]

I have never done that swap but most probably. Only snag is the E46 DME is for running a 1.9 engine not a 1.6.

[Jim320i]

Thanks Barry. I'll have a look into this further. Seems a shame to break this e46 so if I can put something in it and get use I would prefer that.

[Andyboy]

The old E36 1.6 and 1.8 M43 won't do because the E46 unit has the crank sensor at the back of the block, from the toothed trigger wheel on the back of the crank. I'm told you can plug an E36 sensor into the loom and run it from the front pulley but I haven't actually tried it or seen it done.
The 1.9 Compact engine is an E46 type unit. I'd just look for a good 1.9 unit, but alas they're rare in good nick.

[Jim320i]

Cheers Andy

It's on the back burner at the moment, got about 8 breakers to cut through before I get to even looking at these yet so I'm sure there will be more scrap to choice from when I get there