Best m50/s50 years?

[E30_pilot]

Is there a certain m50 or s50 year that is more desired for the e30 swap? and for the m50 from the E36 or E34 better, same or doesn't matter? also for the 2.5 or the 3.0 m50, each is more better for the e30?

Thanks much....

[Jarvis]

'92 325i was NON-VANOS (M50B25), 93-95 had VANOS (M50TUB25).
Only the '95 M3 had an S50 (S50B30US).
Anything newer than that and you're talking about OBD2 motors - which add ~$1K to the swap to do it right, but ultimately have more power potential.

Well you need the oil pan and pump from the E34 anyways, so it would be slightly more convenient to get an M50 from an E34 instead of E36. But E36 M50s have longer wiring harnesses - that way you can route the ECU back to the stock E30 location. IIRC E34 wiring harnesses are too short for that, so you'd have to mount the ECU under the hood where the battery is on cabrios.

[E30_pilot]

thanks for clearing that up for me....

[Ferret]

Keep in mind if you get an E34 engine that you'll need E36 exhaust manifold and aluminum engine mounts.

[KangamangusDriver]

As well as E36 engine arms since the E34 do not fit the mounting points on an E30. Keep in mind you will want to run a tap through these fittings on the block of the M/S50. It will help the when bolting the engine arms in.

[86325e]

I used an E34 motor and was able to pull the relays and DME in through the stock location.

[asubimmer]

so would it be better/easier to use a e36 or e34 m50?

[86325e]

I felt it was easier to go with an E34 engine and just get the E36 engine mount arms and thats what I did. The E36 harness is a little longer though. Personal preference

[asubimmer]

cool cause i think i am going w/ the e34 just wanted to know what others thought.

[E30_pilot]

i think i might go with the s50 swap.
now it's a matter of finding the engine lol