M110 exhaust manifold

[Robert Warren]

I am looking for an exhaust manifold for a 1974 280C and would like to know how many different types were made. What I have now is "california thermoreactor"( junk) I know that a 126 280 SE manifold will not? Looks like it will hit the firewall. Is this manifold I looking for a 114 only.Any help or opinion out there. Thanks Robert

[mbbuff]

Robert, the ones off of a 73 M110 will work. You may have to get the whole M110 system, or adapt yours to the 73 headers. They're a pretty neat cast iron set too.....look like real headers, only heavier. Just be aware that if you have emission testing in WA that requires the Thermo. setup, you may have a problem. I know in Idaho they (emission folks) don't know the difference, because the car is older than most of them, and I don't think they know what they're looking at anyway. Good luck. I hear that thermo. system is a real pain and the heat from it does a lot of under hood damage, especially on the right side.

[Robert Warren]

Mb, thanks for the quick reply,just as I thought M110 only,probably 114 only,maybe123..If I can't find some 'll just have to weld up some headers. Robert

[alabbasi]

I have a set for a M-110. They came from a Euro 280SLC but look exactly the same as those on my 72 and 73 280CE's. They are two piece set up with 3 cylinders for each manifold.

[mercmad6.3]

there are dozens of different variations including the cool RHD units with the air pump ports. practically every M110 i have owned has had different exhaust mainfolds. I scrapped a Ex South African W126 recently which had the best looking ones ever,like Al's these looked just headers made out of cast iron. This a set of W114 RHD exhaust manifolds.

[Pooka]

I don't know what the reactor looks like on that engine, but I had one on a 230 and it just had one big port coming out of the back.

To replace it I needed the exhaust manifold off of a non-California car and the down-pipe that runs from the back of the manifold to the exhaust pipe. Here in Oklahoma any car older than 15 years can be modified in any way the owner desires and there are no safety inspections or emissions tests.

Something I discovered while going through this was that while reactors can be welded up and made to work again no welding shops will touch the job. As they do not know the difference between a cat converter, which by law cannot be repaired, or a thermal reactor, which works entirely differently from a cat, they just don't see any reason to take a chance on is what they are doing legal.

Also, cars from that era were called 49-state cars or California cars. It just depended on the emissions package. Mercedes had 'Western Zone' cars and the Western Zone included all the way to New Mexico. Almost any Mercedes you will find in a wrecking yard in any western state will be a Western Zone car.

For what it is worth, Porsche 911's and VW bugs from this era also had thermal reactors. How the Porsche 914 passed without them I just don't know.

Hopefully some of this info will be helpful.

[Robert Warren]

I think Alabasi is right about the configeration that I need, a split manifold on side going down the front side of the crossmember and one side in back. That is the way the present thermo is. I have a couple of leads to follow up on one has lead me to a nice SLC that might be mine for the taking. Is it true that a 70s sl &slc have the same subframe as a 114 and some parts clear to 91 will fit?. Thanks for all the imput is any body does have a set to sell please PM me. Thanks Robert

[alabbasi]

Take a look at this Video.
At about 1.30 you can get a good look at the manifolds.

[alabbasi]

If anyone is interested, i just listed a set for sale.
M110 Euro Manifolds 280CE, 280SL, 280SLC, 280TE