Been A Proud Owner Of My 82 300sd For About A Year Now. The Car Has Alwats Run Well. At Least As Far As I Knew. Well Todaythe Car Blew My Doors Off. I Have A 7% Grade About 3 Miles Long By My House, The Car Flew Up It Like Never Before, Half Pedal And Asking For More. I Was Amazed...
To Get To The Point, I Was Asking Myself What Is Different Today.i Noticed That I Had Selected A Different Vent Setting On The Climate Control. Started Switching Settings On The Control While Going Up The Hill And Found Where It Runs The Best And Worse. Got Out The Flashlight Consulted Manual And Found Exactly Which Vacuum Motor Was Leaking At That Setting.
Fixed That Now I Have A Brand New Car. I Mean "new" I Found This To Be A Very Easy Method Of Identifing The Place To Look As Far As The Climate System Goes. This May Be Old Hack To You Veteren Mb Owners, I Have This Site For Giving Me The Pieces To The Puzzle. So I Could Solve The Problem.
See Ya , Goin For A Drive!

For the life life of me I can not understand why a vacuum leak would hurt the performance of the car but if it works go for it!

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1977 300D Lost coolant while someone else was driving
1983 300D Can't run without oil
1985 300SD (gone but not forgotten)
1990 300TE 4matic Sold
1991 Yamaha Venture
1975 Kawsaki 250 triple
1974 Honda 200CL
1951 8N Ford
2008 Wildfire 650C

I don't see any possibility of the climate control providing additional power or taking power away from the engine, with the one exception being the a/c. When the compressor engages, the engine loses about 10 hp to the compressor. This can be the only explanation if it is climate control related.

You sure you didn't lose the wastegate hose (maybe cracked?). It's common in these 20 year old vehicles.

well,after reviewing my own composition. i found that i failed to mention that the a/c was on the whole time. il live in palm springs and a/c is gimme.
starting over the a/c was on the whole time on auto mode. all hoses are in good shape and where they should be. i just know that it shifts alot bette, shuts down like right now. even the brake pedal has got better.
please let me know if this makes a difference.or did i just get lucky

Sounds like a vacuum leak went away, which is all fine and well. But the vacuum for all the stuff you mentioned - brakes, climate system, engine shutoff - is supplied by the engine driven vacuum pump. Being a turbocharged diesel, the engine produces no manifold vacuum, unlike a gasoline engine. There's no way any changes to the systems you mentioned are going to affect engine performance. Maybe a clog in the ALDA line freed itself up?

- JimY

Could it be he had a vacuum leak in the climate control system and that this was affecting the turbo control? By setting the climate control a certain way, the leak was shut off allowing the turbo to work correctly for the first time?

Perhaps you need to go over the climate control system and fix the leak?