e36 M50 short block in the e34?

[Dave M]

May be a silly question, but would rather not make a stupid mistake. I'd like to assume that an M50 is an M50 and will bolt up to the 525im without a hassle.

Any issues?

Thanks,

Dave

[JAlfredPrufrock]

Aren't you an M20 seeing as that's a '91? I mean, unless you swapped already.

M50 is not an M50 though, you have the non vanos M50 and the M50tu in '95s.

Don't know what you mean by a short block and don't know if there are any differences between the blocks of the two but just thought I'd throw that out.

[bjl4776]

Yea, the shortblock is the same. The block is same for all M50s and the difference between the 2.5 and 2.8 is a different crank and rods. The only difference comes when you get to the vanos/ non-vanos issues with the head, but the shortblock is the same regardless.

[winfred]

the block and crank are the same on all m50s over here, the pistons have different compression ratios (non vanos is higher) between vanos and non vanos but i don't think that would cause any issues

[Dave M]

Thanks all,

JAlfred, M50s were available in 1991 (my 525 is an October 1990 build date). The block is also from a non-vanos so no diff. in compression. I've written the cheque and a 'rebuilt' M50 block will be on its way soon (new rings, rod bearings).

Next winter's project will be the swap :)


Dave M

[JAlfredPrufrock]

Wow I had no idea there were M50s in '91.

[Interceptor]

Wow I had no idea there were M50s in '91.
The M50 debut in late '90, and M50TU (VANOS version) started shipping in '93. In case you want to know, M52 had VANOS from the start, and M52TU got double VANOS. M54 has double VANOS from the beginning.

[ryan roopnarine]

......i don't know if by winfred not saying anything, that no issue exists, buuuttt.....

it was always my understanding that the e36 m50 engine had a lower oil pan than an e34 m50. you've asked about a short block, which i would assume is everything below the cylinder head, which would include an oilpan. i don't know if its big enough that it will cause issues traversing normal roadway obstacles when installed in an e34, but you should be aware that there is a difference.

[Dave M]

I'm swapping over my oil pan in the process, so shouldn't be any issues. I didn't know there was a difference, you learn something new every day......

[Brandon J]

You have to swap the oil pan and oil pump from the e34 over to the e36 M50.

[Jon K]

Most people consider the oil pan to be an "ancillary" part.... since it houses the pump and such, which isn't traditionally included with a short block.

After much research, i've discovered that the M50 non vanos is the way to go especially for FI.

Reasons:

10.0:1 compression vs. 10.5:1
Connect. Rods bulkier than that even of the S50!
Different pistons means easier/more room for bore!
Double Valve Springs from default! Means higher rpm range than M50TU
And of course the cam timing is more advanced... easier to tune to (no vanos) and better cams for a FI car.