Just want to be sure a 79/80 will bolt into a 84+ 300SD. For some reason the turbo seemed smaller.

Yes no and maybe. They are all t3 flanges so they will bolt on. However your 84 might have a KKK where the 80 is almost certain a Garrett. Does the 84 have ARV?

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1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

Me dumb - ARV?

EGR -yes.

Take a pic of it. There will be lines that run from the EGR to the turbo I think. Either way they can be removed, plug the egr and remove the lines from the 3/2 box on the valve cover. Search around there is info on all of it.

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1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

The ARV is a valve on the side of the compressor. If your compressor housing has some vaccum lines running to it it has ARV. I would just disconnect it, or replace it with a non-ARV compressor housing though.

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1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver

1982 300SD - 232K miles - Wife's Daily Driver

1986 560SL - Wife's red speed machine

The exceptions are 85 Cali car's turbos. They have to be reclocked.

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green 85 300SD 200K miles "Das Schlepper Frog" With a OM603 TBO360 turbo ( To be intercooled someday )( Kalifornistani emissons )
white 79 300SD 200K'ish miles "Farfegnugen" (RIP - cracked crank)
desert storm primer 63 T-bird "The Undead" (long term hibernation)

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