Digital BW, The Print

Changing to the "regular" speed might give you the dry time you need. 
If not you could try and adjust the inkdensity slider (if present) in 
the driver. And if that's not their, or it doesn't fix the problem, you 
will have to play the paper game in the driver. Change to different 
paper types until you find one that give a correct amount of ink on the 
paper, then make a profile for those settings.

Or get a RIP that lets you control the ink limits (among other things).