"Water Pump Each pump is manufactured from T6 aluminum and features an impeller with curved vanes for maximum flow, pressure and equal distribution to both sides of the block. It also features a unique seal assembly for leak proof operation. 3/4"" shaft with 5/8"" fan pilot snout. 1/2"" NPT hole on passenger side (for heater hose) and on top. Stamped steel rear plate. Extra thick fan hub. 3/4"" ultra duty bearings. Adjustable cam stop. State of the art aluminum castings. Equal flow to both cylinder banks. Precision impeller. Higher flow rate and pressure rate. Weighs 6 lbs. Does not have a set screw retaining the fan hub. NOTE: This pump is designed for street use and is not to be run on a motor which exceeds 5,500 RPM. Learn how to choose the correct water pump for your application by reading our tech article. SBC - Short vs Long Water Pump. Bolt Kit A bolt kit for a S/B Compatible with Chevy short water pump. All feature that unique King Chrome premium chrome plating. Fits Small Block Compatible with Chevy (SBC)."