i have a friend how has a engine from a 95 e36 m3, and i would like to know if it can be swapped into my 95 e34 525i. its just the head and block. want to know about what the differences in the fly wheel or harness connections my be.
I'd think you might want at least an E36 M3 DME as well - I'm _guessing_ this would be a direct swap - you can use realoem.com to lookup and compare part numbers (same part number for clutch & flywheel for instance, then you know that part would work fine). Google or search E36 engine swaps (I think threads abound on bimmerforums.com, for instance) and that might get you a better idea about the engine harness (lookup that part number too). I don't know if there may be additional sensors or inputs for the M3 not part of other M50-powered vehicles including yours that might require the M3 harness. Kind of an unusual swap into the heavier car, but it ought to make for some accelerational improvement over stock. I'd suggest poly engine & trans mounts (see vorshlag.com), a short-shift kit (see http://store.uucmotorwerks.com/uuc/articles/main.htm), and researching any S50 weak points while you have easy access to all parts of the engine (new seals & gaskets of all kinds, oil pump nut issue, etc - see if there's an S50 faq on bimmerforums.com), and so on. It's a bit of work, so hope the E34's in good-enough condition to warrant the effort. The stock trim on the bottom of the doors are supposed to drain water, but the passages are miniscule & easily clog, making for a tendency to rust and rot off the bottom lip of the doors. It's a bit more wind noise and a lesser-ideal aesthetic perhaps, but I pulled mine off so water would drain out instead of just sitting and rusting. It's a lot more work (probably expense too), but if you want a funner hp/weight ratio, swap that engine into an e30!
Everything MGarrison said is correct. Putting in the long block S50 will make some difference, and it would be better with more M3 parts. It would really feel better with an S52 from a later e36m3. The S50 will not make a huge difference, especially for the amount of work involved. Think about using the M3 clutch, which may require the m3 flywheel. I have done both s50 and s52 into e34 and e39 cars---the s52 into e34 is best---even in a wagon it's fun. If the S50 is all you can do, I'd say 'go for it'!
it sounds like it wouldnt make to much of a difference for the work involved. my friend is asking 2k for the engine and he would through in the DME. seeing as my engine is getting up there in miles i figured it could be a good buy if it didnt involve some much work and extra parts. sounded like a cool idea but my car needs some suspension tlc first. hopefully after all the work is done i will have some money left to do the swap one day. thanx
