OK, I have read all the relevent posts and DIY articles. I have gotten my 123 shifting great.
I thaught I was so smart that I baught a 300sdl that was shifting hard and I spotted the problem right away. The main vacuum line was leaking. I replaced it and the shifting seemed great. After I got use to the car's extra power and quit pushing the peddle to the floor, the trans now flairs.

My research shows that the 86 only lowers the vacuum to 5psi at full throttle. This is what my gauge shows. 15psi to 5psi at full throttle.
So my question is, should I play with the vacuum modulator valve, the trans modulator, or is it in the boost/vacuum amplifier stuff that my 82 does not have? The bowden adjustment helps alittle but this engine is so strong you just do not need to be in first or second gear very long.

This car just blows away my 82 for acceleration without redlining 2nd gear (like the 82).

My experience is on a 1984 300SD. My vacuum only went down to 5 at full throttle. When I adjusted the vacuum control valve so the vacuum went to 0, the flaring went away.

I read that there is a condition of transmission wear that causes the flaring. The way I understood it, reducing vacuum increase pressure in the transmission which overcomes the worn transmission parts.

It won't be long before one of the great minds will give the real facts. For now, you may want to learn how to make the adjustment at the VCV and play with it.

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1984 300SD 148K Gold
1979 300SD 142K Cream
2001 Audi TT Roadster 60K
2005 Chevrolet 3500 13K

HOLY MERCEDES PATMAN!
You are correct in regards tho our pre 85 machines, but in 85 they added the signal amplifier that takes turbo boost to lower the last 5 psi. So I think my VMV is pretty close.

Of course the vacuum amplifier is adjustable as well..simply pull the small round MB button up & you will see a 3mm plastic stud that can be turned with a socket. Turn back & forth counting the turns to see if that can make any difference.

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