Re: 1977 Evinrude 115 Model 115793S
honing rounds the cyl and restores the lubrication cross hatch. allowing to re-use old pistons with new rings.----uses either bead or blade hone to sand cyl surface.....done at home or machine shop
boring is cutting the cyl walls to allow for a larger piston.......usually if the cyl is worn, scuffed too far out of round, cracked, etc....------done at a machine shop......very expensive equipment.
i hope this is what you are looking for......its not a very good explanation.