The Viking Speed Control Assembly provides adjustment of the opening speed of Viking Deluge Valves, and adjustment of both the opening and closing speed of Viking Flow Control Valves. Water hammer, which may result from the opening of a Deluge Valve or opening and closing of a Flow Control Valve, may be reduced by adjusting opening and/or closing speed. Also, use of the Speed Control Assembly, along with the Viking Pilot Pressure Regulating Valve, enables pressure regulation for reducing high water supply (inlet) pressures to lower outlet pressures.