Copper nuts and stainless studs

[tref]

It has been suggested that whilst I have the engine out (actually of the 924, but I hey...I tried there too and thought could be relevant to '44 Turbos) I should replace the exhaust, turbo and wastegate studs and ensure they are fitted with copper nuts.
Given the absolute nightmare getting the exhaust off of the turbo was, I'm inclined to agree. (The main problem was the nuts securing the exhaust to the wastegate were rounded, and I didn't want to wreck the wastegate studs grinding them off, so I took the exhaust off with the wastegate attached"¦oh yes you can!).

Are they stainless steel and copper as standard? If not, is replacement with these suitable "" I have used copper exhaust nuts before, and seem to recall them as easier to remove longer term. Any ideas of a suitable supplier? All fixings associated with the exhaust system, or just some of them?

Two of the studs came out of the turbo anyway, the other two seem in good health, and I am inclined to leave alone, in preference to breaking them off and having to drill them out.

Any arguments and opinions gratefully received!

Regards,

Tref.

 

[Hilux]

Steel nuts are ok but use coppergrease. The solvent disappears but the copper stays put therefore ensuring that the nut cannot weld itself to the stud.

I use a nut splitter its far easier

 

[tref]

I use copperslip anyway, but the steel nuts on the turbo of our Audi hack-about, are all but gone - I hope the rest of the car turns to dust before I have to undo those, so was hoping for something less sacrificial (obviously not at the expense of the turbo!). I think I would struggle to get a nut splitter (at least the one I have) in place even with the engine out of the car.

I think it should actually be brass nuts that were once commonly used for exhaust manifolds? Has that changed purely for reasons of economy?

Tref.