Listers -
As a former merkur xr4ti guy, I maintain my subscribtion to thier list.
Found an interesting report/how to on water injection after the turbo on
this page. Although it is relating an installation on a turbo xr, the bulk
of it could easily apply to our Audi turbo's. Take a gander at
http://home.ccci.org/Key_Information/MerkurPage.htm#H20 Injection
Tom Nestor