i ordered a 15" magnum d2 but i didnt get a box yet. my friend says i could use his box. its a 15" and its ported but its only like 2 cubic feet. i do plan on gettin another box but how will the magnum sound in this box

Depends on what it's tuned to, but that box is too small for a Magnum 15...more along the lines of a Magnum 12" if anything. I would personally wait until you get a correct enclosure built for a Magnum 15.