Tom, I shoot mainly paper negatives in pinhole cameras, and mainly contact print them, but have enlarged some of them (in a 4x5 condensor enlarger.) My best result was a 4"X5" enlarged to 11"x14". You will lose contrast and resolution in the enlargement, as compared to a contact print. There will also be additional optical artifacts from running the enlarging lens wide open, mainly off-axis, along the outer edges of the print.
As I recall, I ran the lens wide open on my Beseller 4x5, with a print exposure time of 45 seconds to 1 minute. The lower contrast can be somewhat compensated for by the correct choice of contrast filter, although if you're using multigrade paper for your paper negative it probably has too much contrast already, so this may print with okay contrast. You'll have to experiment.
Make sure you place the negative emulsion side down in the enlarger's negative carrier; the paper backing will act somewhat like a diffusion enlarger head. But you really need an enlarging lens that has a flat field wide open, almost like a process camera lens. Or a much brighter light source in the enlarger, and stop the lens down a bit.
EDIT: I've also experimented with APHS film as an inexpensive, ortho substitute for paper negatives for enlargements, but cannot yet tame the excess contrast like I can with grade 2 paper negatives. In my experience, contact prints from grade 2 paper are very nice, and little or no issues with dust, etc.
~Joe