1621 1973-1987 Buick Cadillac Chevy GM Olds Pontiac Grand National 196 231 350 4.5" water pump

Flowkooler high flow pump 1621 has a 16 vane CNC machined billet impeller.  It is shrouded and ported and, with the increased vane count and a reduced impeller clearance, it really pumps the coolant.  It achieves greater flow rates, higher head pressure and a more efficient flow. The impeller's color is due to Type II Class II military grade surface coating which protects against corrosive fluids.  FlowKooler introduced the first hi flow pumps and continues to improve impeller design. Why is increased flow so important to cooling a hot  engine? Because it has been proven time and time again that reducing the cycle time between the heat source and the heat sink creates more opportunities to shed heat and drop engine temperatures. From 0-3,300 RPM…Nothing Beats a FlowKooler! General Specifications: Type of Material of Pump Body Aluminum Number of Blades on Impeller 16 Direction of Rotation CW Fan Hub Height 4 1/2" Shaft Diameter 5/8" Hose Connections: 1st 2nd Gender M NA