How come some W123/W126 OM.617 powered cars have very obvious large air cleaners over the turbo assembly area and other cars do not?

The only ones that don't have a stock air cleaner in that location are the 85 california models that have an even larger canister shaped filter. Other than that, they may have an after-market "K&N" type filter hack. Those cars should be avoided, diesels don't run very well on dirt.

lolololololololloo
Sorry Craig,, that was both funny and the truth. Maybe that's what made it so funny?

Actually, the only thing wrong with the 85 california canister filter is that the filters are so damn expensive. Other than that, it has a straighter path to the turbo and the ram air effect of the cold air intake is slightly better due to a shorter hose run.

Well.... I guess there is another problem with it. It occupies the best place to put an air/water intercooler.

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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)

http://ecomodder.com/forum/fe-graphs/sig692a.png

Are these the ones you are talking about VWGuru?

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That is it.

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'85 300SD (formerly california emissions)
'08 Chevy Tahoe
'93 Ducati 900 SS
'79 Kawasaki KZ 650
'86 Kawasaki KX 250
'88 Kawasaki KDX200
'71 Hodaka Ace 100
'72 Triumph T100R

Yep, those are them...supposedly the '85 Cali models have trap oxidizers? I thought those were only on W124s though...

So I went today and drove both the NA 300D and the turbo 300D. The euro one I actually was kinda blah about. I drove it and it was still torquey and had no trouble in real world, California driving situations. I still liked the punch of the turbo though.

The 85 W123 cali cars also had the trap oxidizers, those are the ones with the large air filters.

As tough as OM617s are, I think they would, just not very smooth!

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91 350SD
14 F150 Eco
19 Fusion Hybrid
11 GT500

... and it continuously hone the cylinders while you're driving.

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'85 300D Turbo - CA Version