I have a bad exhaust leak here and I'd like to know what you guys use that lasts and won't give over time.
I'm looking at Ultra Copper Seal but if you guys know what works best, please let me know.

Type of Sealant used here?

This is the area I need to seal.

 

the factory uses nothing there, its just two flat pieces of iron. i would suggest pulling off the back plate and sanding it flat. if the studs come out of the turbo then do that as well.

the turbo runs around 700c, so if you do use a sealant, it needs to be high temp.

 

That was some nasty high temp sealant from mcmaster-carr. I think it was like powdered lead in a goo.

I used some very thin copper cut to a gasket there too and it would work and last a while.

But finally machined the backplate flat again (warped from welding) to fix the leak and it didnt need anything to seal like stock piece.

 

Thanks for the advice fellas!