my exhaust turbine blades are scraping against the backplate of the exhaust housing, which is loose and spins.
is there any way to get the backplate to stop moving?
its a big 16g btw

pics coming soon because i dont know if my terms are accurate

 

 

It is normal for that shim plate to spin. If it didn't you would have problems. If it didn't it would indicate oil coking up and causing it to not spin. The only thing you need to worry about is shaft play. If you are experiencing shaft play then you need to check for boost leaks.