are preferably concentric with respect to a central axis 38 the valve seat 50 is substantially circular and has a valve seat diameter 58 that is greater than a valve outlet diameter 60 shown in fig9 and 10 the valve outlet 52 is also substantially circular in the example embodiment the valve seat diameter 58 is approximately three inches to allow for a sufficient amount of water 28 to flow both during the initial inrush of a flush cycle and during the balance of the flush cycle the passageway 48 reduces the larger valve seat diameter 58 to a valve outlet diameter 60 of approximately two inches proximate the valve outlet 52 as a result the passageway 48 funnels or directs the water 28 toward the bowl 14 providing sufficient bowl 14 cleaning and waste removal water 28 during a flush cycle and to permit coupling the mounting 32 to more traditional components and fixtures the passageway 48 may take on a variety of arcuate surface configurations of reducing cross section with each having a goal of efficiently transferring water 28 from the tank 12 to the bowl 14 during a flush cycle the tapered passageway 48 has the added benefit of making the mounting 32 compatible with standard bowls and other coupling components while allowing the enhanced flow of water 28 the mounting 32 includes a series of supports 62 in the form of arcuately tapered legs that extend inward from the passageway 48 and converge proximate the central axis 38 where they define an opening 64 the supports 62 taper below the valve seat 50 toward the valve outlet 52 to maximize the flow of water 28 through the passageway 48 the.