Z3 timing case on a m42

[e30s50dan]

I just picked up a z3 1.9l engine yesterday.looking to update the sprocket to rail

Can I use any of the timing chain case components for my m42.?

[bmwman91]

Sounds like an M44 timing case. If so, then no it is not quite a direct swap, but it can be done (I am running one). The M44 case bolts up fine and has all the right things in the right places, BUT it lacks the bracket to hold the crank sensor in place. You have to make or buy one. Metric Mechanic can source one for you (I am running one of their M42's with the M44 case installed which they provided a bracket for).

The M44 case is, in a way, an upgrade since the oil pump rotors are slightly larger, so they move more oil. Not that a stock M42 has problems with oiling. You do need to make sure to get the M44 case-to-block gasket since that is specific to it, and anything else you replace in there you should consult the RealOEM diagrams for the M44 to make sure that you get the right part numbers.

[e30s50dan]

What oil filter housing do I need to use?..and can I use the m42 front housing that has the crank sensor bracket?

[bmwman91]

I think that you can use either the M42 or M44 filter housing. Personally I'd go with the M44 housing since IMO it is marginally better due to having 2 rubber o-rings on the clean oil outlet (less prone to leaking). Either one should be fine though. Just be sure to get all mating and sealing surfaces imacculately clean, and don't let crud fall into the round hole in the timing case since that feeds clean oil into the engine.

According to RealOEM, the M42 covers fit the M44 timing case. Also, the crank sensor bracket is part of the timing case casting, not the covers, so there's no way to avoid sourcing the adapter bracket.

[e30s50dan]

When I looked up realoem 318is,I don't see the bracket on the front housing

[bmwman91]

The bracket is integrated into the big timing case part. It's part of the casting. There is no OEM adapter. You need to have one made. IIRC they will run you ~$125, and getting the alignment perfect is a bit of work too. The only company that I know of that sells the adapters is Metric Mechanic.

[fresh_TD]

Bottom left corner of the picture, the portion that sticks out. That's where the sensor sits.

Sent from my Pixel XL using Tapatalk

[cwlo]

Another option is to cut off the mounting on your M42 case, and weld it on to the M44 case.

[e30s50dan]

I have a one from a 95' late m42, but it is now for sale