M5 European Exhaust Headers

Specific conversations and info for the BMW E28 M5 and M535i.
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Syndrome
Posts: 128
Joined: Nov 23, 2021 3:46 PM
Location: DC

M5 European Exhaust Headers

Post by Syndrome »

I’m looking for a set of European exhaust headers to replace the original manifolds on my 1988 M5. First, I’m not sure if these are the right OEM part numbers : 11621307250 cylinders for 1-3 and 11621307251 for cylinders 4-6. Can anyone confirm?

Another thing’s for sure, I don’t know at all what these look like. Does anyone have a picture I could see, please? Do any E28 M5 headers look like the E34 M5 headers? The latter (on my own E34 M5) have a sort of air horn sticking out of each pipe near each cylinder. How do I definitively tell the difference between the E28 European headers and the European E38 exhaust headers? Thank you!
///M
Posts: 74
Joined: Apr 17, 2009 11:21 PM

Re: M5 European Exhaust Headers

Post by ///M »

Hi Syndrome
Maybe because of where you are or your computer or internet provider but I am amazed when people cannot find things that are obvious. I highlight the number in your post and right click on the keyboard/mouse. An option comes up to search the web for the highlighted text giving a number of results.
https://www.schmiedmann.co.uk/en/produc ... -1-307-251
This should show you a picture of the European manifold.
They are only for LHD cars only. The RHD had a simpler manifold as the steering box interfered with the design of the LHD manifold. Rather than go to the expense of a major redesign BMW took the cheap and easy option. The RHD manifold is a simple 3 into 1, possibly like the US version. (There was never any change stated in the power output 286BHP)
If your car is the US version then it is rated at 256BHP. A detuned version of the Euro motor.
Was that a money saving, emissions or simply unnecessary deletion of the Euro part?
The E34 M5 Manifold has two nozzles for injecting air for lower emissions on startup. Inside there are tubes sticking into the manifold. They can act as a restriction in the exhaust. If emissions are not an issue then the additional air pump can be removed and the two air injection nozzles ground smooth.
Syndrome
Posts: 128
Joined: Nov 23, 2021 3:46 PM
Location: DC

Re: M5 European Exhaust Headers

Post by Syndrome »

Yes, I saw the referenced information. Because I just want to corroborate what I saw with a real person’s information, I asked. Sorry.

Having said that, please let me ask you a question specifically about what you said:

If I were to take a set of E34 M5 headers and remove the air injectors, would these then be exactly the same as the E28 M5 headers? My own thinking is, maybe yes and maybe no. In flow, maybe, according to what you said already, but my limited understanding is that the E34 M5 headers won’t fit into the E28 chassis. Am I wrong?

Will E34 M5 headers fit into the E28 M5; would they be the same as E28 M5 headers in terms of performance; and are there any physical differences apart from the air injection horns, i.e., pipe diameter (internal and external)?

Thank you.
///M
Posts: 74
Joined: Apr 17, 2009 11:21 PM

Re: M5 European Exhaust Headers

Post by ///M »

Hi Syndrome
With regard to your questions some are straightforward, is the E34 manifold the same as the e28? the answer is no. The shape is different. The construction method is different. The E28 version is welded sections the E34 is hydroformed.(search hydroforming process) Have a look at your E34 manifold, it has smooth continuous bends with the only welds at the joints.
Will an e34 manifold fit the e28 chassis? It will bolt to the head but may interfere with the engine mounting and the connection to the exhaust at the downpipes is different.
If I was in your position I would get the Euro manifolds, but if they improve performance on the detuned engine I do not know. They may need some work at the join to the exhaust depending on the connections that are on there. You would need the input of someone who has done this. Without before and after dyno results bear in mind that the results are always subjective.
I have an E34 M5 engine to fit into an E28 chassis but it is a RHD car. If it was a LHD drive it would be easier as there is no steering column to work around. So fitting an E34 manifold should be straightforward to a competent person.
cinnamonandgravy
Posts: 61
Joined: Jun 20, 2009 7:37 PM

Re: M5 European Exhaust Headers

Post by cinnamonandgravy »

I have (as far as I know) euro headers in my us e28 m5...the "bundle of snakes" ive heard it called. (maybe theyre e34 instead of e28… dont know.)

it installed fine but sometimes slightly bangs against the heat shield when at very low speeds, turning, and at low RPM. no biggie, doesnt happen often.
also, they will not mate to a stock center section, so youll either have to modify the headers or the center section (2 bolts vs 3 bolts, if i recall correctly). i opted to modify a vsr high flow center section because i couldnt stomach the thought of altering the headers themselves (theyre pretty).

not sure if true, but something to look for i suppose: earlier euro headers were whole tubes bent into shape, whereas later headers were many pieces of tube welded together.

if going through the trouble of adding euro headers, might as well ceramic coat them as well.

ill take a picture (if i can remember to do so).
cinnamonandgravy
Posts: 61
Joined: Jun 20, 2009 7:37 PM

Re: M5 European Exhaust Headers

Post by cinnamonandgravy »

excuse all the dirt.

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archivecollections
Posts: 10
Joined: Jun 26, 2022 6:16 PM
Location: Los Angeles, CA

Re: M5 European Exhaust Headers

Post by archivecollections »

Hey Syndrome,

I saw that you're looking for European headers for your S38B35 engine, and I wanted to recommend Supersprint's S38 Euro headers. Interestingly, I've ordered a set for mine so I can post photos after I receive/install them ;).

I've used their exhaust system for many years... Usually, on my E30 M3s, although they don't make headers for those. However, their S38 headers are specifically designed to improve the power and torque of this engine. With their precision-engineered design, this help unlocks the full potential of your S38 engine.

Additionally, Supersprint is known for its excellent fit and finish, which means it will install easily and look great under the hood.

https://www.turnermotorsport.com/p-3541 ... d-headers/

- Caleb
EuroShark
Posts: 1474
Joined: Feb 12, 2006 12:00 PM
Location: Colorado

Re: M5 European Exhaust Headers

Post by EuroShark »

I've installed three sets of the Supersprint headers and they've gone together perfectly every time. It's not a fun job to do with the engine in the car. Get a sacrificial 1/4" drive 9mm socket and grind the OD down until it's pretty thin. Once you figure out which order the pipes need to be installed in, it's not so bad.

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Preyupy
Posts: 326
Joined: Jun 21, 2012 12:48 AM
Location: Issaquah WA

Re: M5 European Exhaust Headers

Post by Preyupy »

The E28 "European" headers make a significant difference in the mid-range torque on the US spec S38. With the stock European exhaust (without the catalytic converter) I found 25 ft/lb of torque @ 2500 rpm at the wheels. Maximum torque and Horsepower were only up by 10-15 each but the mid-range torque was worth every penny.

Installing them however is not for the faint of heart or inexperienced mechanic. The 1st set took me 10 hours on a hoist with air tools, I was a dealership master mechanic when these were new (I did the PDI on 5 of them that we sold back then). I have a couple of scars to prove it.
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