Huh! That's a new one on me. I've never seen the semi "H" pipe on any M110 I've ever worked on. Could it be specific to the "E" engines?

My '73 280's didn't have it and neither does my '74 280C.

The picture doesn't show but do the two header pipes merge into a single muffler inlet or do they continue back as dual exhaust?

The use of a "H" pipe is usually to compensate for the differing length of exhaust but I don't see how much effect on back pressure the placement of this would accomplish.

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