Craig, i dont know if it is. both my W123's are 1980's and they don't have the dampers just before the IP in the vacuum system. My 300D has always shifted oddly ever since i purchased it, and i think this is due to the vacuum system being totally messed up.
I have looked at the vacuum diagrams but i can only find 1982 and up. Also i don't have a EGR, so that changes the diagram again. I have seen some pictures from other forum members that showed some vacuum "dashpot" devices and i figured that is what i am missing, along with the orifices.

Does phil carry the orifices?

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