S40: Exhaust Elbow to Turbo on T4 Query?

[bar72]

Volvo s40 1998 T4..

are these studs and a nut? or are they straight through bolt and a nut? also, what size, 13mm?

if they studs, can i just use half inch / 13mm nut 'n' bolts as one is missing from the right hand hole anyways, as in, there's only 2 holding it to the turbo prior to fitting replacement downpipe.. further, does it need a gasket to join to the turbo or does engine heat seal it?

thanks for any info.

[Baffler]

They are nuts and studs. I can't remember the size, possibly 8mm stud and 12/13mm nut. They are high tensile so if you use mild steel or galvanised in there they could become welded to the inner thread over time.

When replacing the turbo on my T4 there was also no gasket on the downpipe side but as it was listed I got one for the sake of a few sheckles.

See below for part numbers:

[afzalmj]

They are stud & 13mm nut.

[bar72]

tnx baffler, hitting trouble then as it looks like one of the studs has sheared in the turbo ( still, there's 2 holding it the now with no loss of power, tnx for the diagrams..