Question about M110 exhaust manifolds, W114 vs W123

[juha_teuvonnen]

I have a 1974 (1975 model, CA version) W114 with M110 engine. Factory exhaust is single pipe with catalytic converter. I am installing a pair of exhaust manifolds from euro W123. They are 3 into 1 manifolds, two of them. The Euro M110 had dual downpipes. I looked through some catalogs and I see that earlier W114 also had this manifold setup (3 into 1 and 2 downpipes). Does anybody know whether the manifold flanges on W114 and W123 are the same or not? My W123 flanges are 2 bolts per flange. I was thinking about using either W114 dual downpipes or W123 dual downpipes, to minimize amount of mandrel bending and fabrication (hence lower cost). I am not sure whether the exhaust pipes and flanges are the same on W123 and W114. I thought that W114 were 3 bolt flanges, but I may be confusing them with something else.

The manifold numbers are 110.142.6502 and 110.142.6602 manufactured 19.04.80

[Tomas7]

Let me see if I can answer your question. I did the same thing you're in the process of doing. I did it years ago. I got rid of that awful exhaust system that dumps to the front via a flange and into a catalytic. Here are pictures of my system. As you can see my exhaust has three bots, it dumps into a Y pipe. In other words a two into on system that dumped into a resonator which I deleted. I have a DUAL THREE INTO TWO (Y pipe) into one all the way back to the rear muffler.

My outlets are three bolts but that doesn't matter as long as your down pipe coincides with your outlets.

[petesmga]

I have 2 280SL's, a 79 stick and an 84 auto both cars are m110s and the manifold flanges are 2 bolts.

[280EZRider]

Originally Posted by juha_teuvonnen

I am not sure whether the exhaust pipes and flanges are the same on W123 and W114. I thought that W114 were 3 bolt flanges, but I may be confusing them with something else.

Keep in mind that that the flange connectors on the pipes are not welded to the pipes, so you can always exchange them. Of course to do this the pipe needs to be separated somewhere toward the front to remove the connector.

[petesmga]

Sorry to throw a curve but the 2 hole flanges on my m110's are cast into the manifold.

[280EZRider]

I´m talking about the flange connectors on the pipes - not the manifolds.