Since pin holes do not have a definite focal length the
equivalent f stop is calculated from the distance the hole
is from the image.
  A 1/8th inch hole is too large. A more reasonable size
would be around 1/50th or 1/75th inch, very small.
  You can get some information from Kodak at:
http://www.kodak.com/global/en/consumer/education/lessonPlans/pinholeCamera/pinh
oleCanBox.shtml

The instructions there talk about Kodak Kodabromide paper
which has been discontinued. However, most variable contrast
paper has a somewhere from the same to about half the speed
when used without a filter.

  Another good site is:
http://www.photo.net/learn/pinhole/pinhole
Which has the formulas for calculating the optimum size of
pinhole and its effective f stop.
  The pinhole size is not at all critical. Also, while an
ideal pinhole should have no burrs around the edges the
difference in practice is slight so a pinhole made by
pushing a pin through some aluminum foil will work fine.

   If you use an exposure meter the effective speed of
typical fast enlarging paper is around ISO-5.
   You will, of course, get a negative, but you can contact
print to another sheet of paper to get a positive print.

1/60 of a second for the white side of the paper, and 1/2 second for the
Black side.