One product comes to mind for me. Seafoam!! Unless you have an HOA
With an engine that messed up I would double the amount run it for maybe 300 miles, put in some regular oil, put some more Seafoam in and run it for maybe 1K. Then do a full synthetic oil change.
With an engine that bad I don't know if anything would work though.
By the way the reason I'm cautioning you with the HOA thing. Until the impurities are all but cleaned out Seafoam will make your car smoke like crazy.