m42 vs m44 problemt

[rfbehn]

I just bought a 1992 318i that had the engine changed out.  I think they used an m44 and set it up on odb I.  The exhaust manifold has shims welded to in and when I bought a new oil filter for it, it needed on listed for a 1996 or m44.  How can i be sure that it is a m44 and not a m42.  It also has a barn door style maf.  The intake has some vacuum ports not being used.  The reason i need to know is that i am doing a head gasket job on it.

[DesktopDave]

All M42s have barn-door AFMs.  The MAF cannot be swapped onto an M42 without some pretty major electronics work.  You can positively identify your motor by where the crank sensor is.  Nose of the crank, M42.  On the crankcase near the transmission, M44.

IDK if there is a lot of difference between the two head gaskets...but I've never done one.  Later M42s & M44s have an oil check valve between head & block you have to be careful not to lose.

[fabe]

it may well still be a M42 but the previous owner may have replaced the oil filter housing to the M44 version.. or the replacement engine is the last batch of the M42 which has such oil filter housing...

[nicknikolovski]

M44 engine uses a single coil pack Vs. M42's 4x coils individually. Also M44 uses a rocker arm valvetrain Vs. hydraulic lifters (M42). The airbox is also different on M44, uses a MAF sensor as DesktopDave mentioned. Also the head gaskets are different. You will know straight away if you remove your valve cover - if you can see rocker arms - its M44 otherwise its M42.

[rfbehn]

she has no check valve on the head,  and lifters not rocker arms.

[nicknikolovski]

There you go then, its an M42. It may just be a later production version. Just get the M42 >/92 head gasket set.

[fabe]

I thot I read somewhere in this forum that those who bore out the M42 block use the M44 head gasket as the cheaper alternative to those aftermarket head gasket cos it has bigger bore, IIRC 85.5mm...