Molding chamber arrangement (1) for a mold-string plant comprising a molding chamber (2) formed by a chamber bottom (3), a chamber ceiling (4) provided with one or more sand filling openings (22) communicating with a sand-feed system (14), two chamber side walls (5), a pressure plate (6) provided with an exchangeable pressure pattern plate having a pressure pattern (8) and being connected to a movement mechanism (9), a swingable plate (10) provided with an exchangeable swing pattern plate having a swing pattern (12) and being mounted for translational and swinging movement in order to open and close the molding chamber (2), allowing the pressure plate (6) to expel the produced molds, and further comprising means (13) for vertically moving the chamber ceiling (4) and sand-feed system (14) in unison, or the chamber bottom (3), or both, relative to the remainder of the molding chamber arrangement (1), thereby changing the height of the molding chamber. By this arrangement, the flexibility of the size of the produced molds, especially the heights of the produced molds, can be adjusted without changing the geometry of the sand feed system above the molding chamber in a time-saving manner.