Double Threaded Stud to Turbo


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Apr 26, 2018
Can anyone confirm the size of the three studs from the up-pipe to turbo inlet on turbo . It's either 3/8" - 16 x 2 1/4" or M10 - 1.5 x 2 1/4"
I want to replace these studs but need verification before proceeding.
Thx in advance.
I chased down my answer.
Another question - Where can I find / purchase the bolt & spring for the turbo down pipe & what the hell do you call that type of bolt ???
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Did the bolts end up being metric or standard? I don't know how to spec the springs but those are shoulder bolts. Bolt Depot has a vast selection of fasteners in every grade and material you can think of, that is where I would check.
The bolts on the OEM Garrett Turbo are Metric.
The three up-pipe double threaded studs ("Set Up Stud") are M10 - 1.5 - 57mm
The two down-pipe "Shoulder Bolts" are M10 - 1.5 - 68mm > with the "shoulder" 48mm length (12.5mm thick) and thread length 20mm
Thanks for the lead.
Are the threads the same on both ends of the up pipe studs? I am in need of a set of the same studs.
I have these, three matching $30 plus shipping.
The others are an odd lot. There is another set, but only two bolt heads match, if it makes a difference. Also $30 plus shipping.