[gnaritas]

No, stellar black holes have less mass than the stars they came from. When a star goes supernova it ejects much of its mass, the core can collapses into a black hole. Black holes don't form due to mass alone, but density of mass. Collapse the earth to the size of a golf ball and it'll become a black hole, but of course the earth doesn't have the necessary gravity to do that. Neither do stars, until their cores collapse and get dense enough to cross that line and become black holes.