S52 (US) parts interchangeability.

[MaxBell]

Hey guys;

I have an OBD2 S52 I'm putting together and it's missing a few parts. I have an M50 in the car right now that I'll pull into for the parts if they fit. Otherwise there's an M52 local that I could pick up? Are any of these parts specific to the S52?

So, do the M50 or M52 parts work for any of the following parts:

Valves (my S52 has 7 bent valves)

MAF (didn't come with my motor)

Crank Position Sensor (didn't come with my motor)

ECU (didn't come with my motor, no idea what the number should be [white label? red label?])

[craz azn]

Why not just run your S52 as OBD1 if you already have your M50 in and running? Might be easier for you instead of piecing it together... just a thought. All you'd need is just a chip and you are good to go!

Anyways, if you are making the jump to OBD2, I have the proper maf and a cps if you need... PM me :)

[sweet3]

The MAF are different (different connectors)
CPS are different (one is in the front of the block, and the other is in the rear of the block)
ECU:
- 413 red label (OBD1 no EWS)
- 413 silver label (OBD1 with EWS)
- not sure about OBD2

[Wanganstyle]

Hey guys;

I have an OBD2 S52 I'm putting together and it's missing a few parts. I have an M50 in the car right now that I'll pull into for the parts if they fit. Otherwise there's an M52 local that I could pick up? Are any of these parts specific to the S52?

So, do the M50 or M52 parts work for any of the following parts:

Valves (my S52 has 7 bent valves)

MAF (didn't come with my motor)

Crank Position Sensor (didn't come with my motor)

ECU (didn't come with my motor, no idea what the number should be [white label? red label?])

easiest option is to:
strip the S52 to a shortblock only;

remove the cam trays, vanos assembly, camshafts, lifters for re-using with M50b25 head; its the same cylinder head casting. the M50 valvetrain and head is close enough in specification to be fine for street use with s52 cams and lifters.

Genuine S52b32 cylinder heads from a WBS car have higher rated valvetrain installed from BMW, otherwise the casting is identical to any M52 casting. BMW has a Vin number sticker on each cylinder head to identify it when off the car.

the M50b25 casting is slightly different and also interchanges; there is also a different number (not #400) for very ~1993 early Vanos M50b25 heads, its got one less water port hole open but it interchanges the same as any 400.

the 840 casting Non-vanos head also natively takes a vanos camset+trays+vanos drive happily; they have slightly different chamber shapes but are close enough that the factory DME will run it without isssues for street use.


Strip the complete M50b25 of its sensors, intake manifold, cylinder head and vanos Solinoid for the longer wire tail. use the M50b25 wiring harness and DME as you already have it installed and working and have all the parts; KISS


end result:


M50b32 with s52 cams and obd1 electronic everything. call tuning house of your choice and install chip for S52 obd1 (we ran a TRM)

common frankensteins are M50b32 m50b28, s50b32, m52b32 (designated by head/block;- race cars often run aftermarket cams) - a REAL S head has better valve springs that are shared with S62b50 and ironically the M42



using a 3200cc shortblock will require using a S50b30 or s52b32 head gasket;

[surebimmer]

Check your 400 casting heads. As i have found that all 400 castings don't have the extra cooling ports.

http://www.r3vlimited.com/board/showpost.php?p=2437461&postcount=1

The valves are the same just different valve springs as Wanganstyle stated. Pretty much just listen to the above post.