Is this true: I'm being told S52/M52/S50/M50 heads not interchangeable

[NoSoup4U]

A BMW dealership is telling me that I can ONLY use an S52 head. I have a 1997 M3 head that is cracked in three places. I am trying to locate a replacement head for it.

The BMW dealership tells me that the 95 S50 head and early M50 heads will not work b/c the vanos is different from the 96+ S52 vanos's. They also say that the M52 head will not work as well.

Is this true?

They said the M52 might bolt up -- but, problems will occur regarding software and I would need custom s/w, etc. But, definitely S50/M50 will not work b/c vanos is different from the 96+ years. If this is true, makes it much more difficult to find a head. I hope some of you FI people will know and can help.

p.s. -- anyone have a remanufactured/rebuilt/used head S52 that they can sell me?

Thanks,

James

[BlownM3]

A BMW dealership is telling me that I can ONLY use an S52 head. I have a 1997 M3 head that is cracked in three places. I am trying to locate a replacement head for it.

The BMW dealership tells me that the 95 S50 head and early M50 heads will not work b/c the vanos is different from the 96+ S52 vanos's. They also say that the M52 head will not work as well.

Is this true?

They said the M52 might bolt up -- but, problems will occur regarding software and I would need custom s/w, etc. But, definitely S50/M50 will not work b/c vanos is different from the 96+ years. If this is true, makes it much more difficult to find a head. I hope some of you FI people will know and can help.

p.s. -- anyone have a remanufactured/rebuilt/used head S52 that they can sell me?

Thanks,

James
The head might in fact bolt up. Just check part#'s for headgaskets , if they are the same it will bolt. If the Vanos system is different it might be a problem. The camtiming on the obd2 car is very picky. A lot of times after changing a head gasket you have to retime the cams once you are able to fire it up. So if the systems are different it might have an issue.

[Fissionx]

i'm pretty sure the VANOS units are the same, i'm running a S52 vanos unit&solenoid on my 328 w/ no problems.

[ericcamaro]

The problem is that the late model s52-m52 has two vanos units, one for the intake and exhaust cams while the m-s50 only has one on the intake cam. there will be no problem with bolting it up but you would have to run obd1 software with it for the vanos to work properly. However If someone with an obd1 car could possibly use a s52 head on an m50 but there is alot of stuff that wont be functional.

[aceves]

The problem is that the late model s52-m52 has two vanos units, one for the intake and exhaust cams while the m-s50 only has one on the intake cam. there will be no problem with bolting it up but you would have to run obd1 software with it for the vanos to work properly. However If someone with an obd1 car could possibly use a s52 head on an m50 but there is alot of stuff that wont be functional.
I'm pretty sure only the m54 has dual vanos

[Shuasha]

The problem is that the late model s52-m52 has two vanos units, one for the intake and exhaust cams while the m-s50 only has one on the intake cam. there will be no problem with bolting it up but you would have to run obd1 software with it for the vanos to work properly. However If someone with an obd1 car could possibly use a s52 head on an m50 but there is alot of stuff that wont be functional.
Yeah, you're way off. The Euro versions had intake and exhaust cams, but the US version didn't get dual vanos till S54.

[Verruckt]

Don't listen to the dealer, it will work. There was a thread somewhere about a M50TU head on a S5x block.

[brew]

In the US, the first motor to have dual vanos was the M52tu which was in the E46 323i and 328i.

[STOLI311]

It will bolt up. I have a 97 m3 with a s52. The head was blown and I installed
a cylinder head off a 95 525i touring wagon. The cam carriers and hardware
bolted right up.. The reason the dealer is probably saying it wont work, is
not because of the casting but the carriers. The cams will not clear the ledges of the carriers if not swapped out. Even at that a machine shop can fab the existing ledges to accomidate the m3 cams unless its a m3 head. Thats why applications for Schrek cams go from 95 to 99 m3. As you already know 95 is a s50..

[NickG]

It WILL fit.

All M50TU (93-95 6-cyl VANOS) and M52 (96-99) use the SAME head casting. The only difference is the OBD1 installs need 2 ports drilled for water temp sensors, while OBD2 installs only need 1 port. You either drill the port if you need it (and the casting doesn't have it), or plug it if you don't need it (if the casting has it).

Just swap your M3 hardware over to the replacement casting. End of story :)

[themadhatter]

James,

just as Nick said. it's the same part number for the actual head no including the accessories.

if you do get a casting with the extra water jacket (M50/S50) - just use it for a water temp gauge. :D

for those of you who have no clue as to what you're talking about, please review your info before you post up please.

-Ron

[NoSoup4U]

Thank you guys. One quick question.

Do I need to do anything to fit the S52 cams into an M52/S50 head? Do I need to transfer the cam carriers, etc?

I believe there is one more port/hole on the M52/S50 head -- how do you plug this and what do you plug it with?

[m3boost]

Well when I converted to OBDI the head of my 96 had the extra hole but had a plug. So I'm sure they sell the plug at the dealer.

[themadhatter]

Thank you guys. One quick question.

Do I need to do anything to fit the S52 cams into an M52/S50 head? Do I need to transfer the cam carriers, etc?

I believe there is one more port/hole on the M52/S50 head -- how do you plug this and what do you plug it with?
James, carry over EVERYTHING into the new head.

for the extra water port, toss in a water temp sender. mine didn't have one so we (bill and I) tapped one into the head but you're lucky on that point.