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Discussion Starter · #1 · (Edited)
Anybody know the exhaust flange collar stud diameter and thread pitch on a 97 Dodge Cummins' turbo outlet cast iron elbow?

The ones that (were) in place threaded in all right, but wiggled around some...not right, and to prove it they unthreaded themselves :rasta: .

Eddie
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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Your talking about the 4 studs that hold the turbo to the exhaust, there M10x1.5.
 

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Discussion Starter · #3 · (Edited)
Well, I Fingered It Out--Not To Say I Fixed It...

1994-'98 Dodge Cummins 12-valves have a 45-degree, cast iron elbow with a smooth-surface, 3" diameter bore.

The turbine outlet and the turbine side mating surface of this elbow have a flat mating surface, mashed together via a one-bolt V-band.

The elbow's other end is a standard ball-flange, meant to mate up with a
corresponding bell flare in the exhaust downpipe's tubing, which has a two-bolthole collar.

This ball-flange has two diametically-opposing, fairly thick, ears cast into it, and those ears have one machined-in holes each. The elbow flange holes and the bolt holes in the collar line up with each other when the exhaust tubing's bell flare is properly positioned on the cast iron's ball.

Studs thread into the cast irons, and nuts hold the flange.

The cast iron ebow's thread size turned out to be 10mm-1.50; yeah, I finally sucked it up and ran the tap that most closely (read, "exactly") fit and almost finished screwing it back together.

Almost...

Did I need to mention that whoever--whatever--Fiend From The Innermost Circle of Dante's Inferno decreed that turbo outlets shall be basically impossible to fool with, should be sentenced to a worse punishment (like having to live with my Ex :puke: ). Fooling around in the turbo area of the engine bay requires lots of Uncle-Daddy Eddie's special medication :)beer: ).

As soon as I run across a pic of this elbow with the studs I'll post it; the Dodge elbow might be a good option for 4BTs, 'cause the cast elbow's radius is so much tighter than a tubing radius can ever hope to be, and I've seen bolt-on V-band adapter flanges out there; the '89-'93 Dodge's had a bolt-on elbow IIRC, and the 6BT turbo might make a good upgrade for a 4BT--I haven't followed 4BT tweaks all that closely.

Eddie
 
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