Digital BW, The Print

This is really frustrating.

I can print a good 21 step gray scale using one of several workflows 
and curves then when I try to print an image I get crap.

The images are processed in PS 7 after being converted with ARC.

Whe printed monochrone on an 890 using color inks (MIS ARC) the 
prints look fine. When printed using the QVM ink set everything 
looks flat, with no strong blacks.

I've tried several different ICC profiles for the different papers, 
default Epson profiles as per th workflow material associated with 
the curves (Roark V13, earlier as well as Boley's) nothing seems to 
work.

Anyone have a suggestion?

David