I was born with a long foreskin overhang. now and then I like pumping my cock. love the feeling of my fat heavy cock. when pumping my foreskin grows a lot. it gets much longer, becomes much much thicker (especially on the more meaty side where the frenulum is) and gets so heavy that it really dangles like a trunk. the cock can stay like that for max a few hours before it shrinks back to normal again. since I don't pump my cock that much I guess my foreskin don't grow any longer, but I'm convinced that there would be now problem growing my foreskin much bigger by using my cock pump.
I have to add that I always pump with my foreskin forward and covering my cock head. the suction in the pump first stretches my cock more then the foreskin so at first my cock head opens the foreskin and glides partly through the foreskin opening, but after a while, on and off pumping and massaging the cock, the foreskin gets longer and longer, and thicker and thicker. my overhang starts to grow longer and longer even my cock is erected.
the real cock trunk appears when my cock gets semi hard/flaccid, hehe.