This pump features KRC's standard 13. 5cc ultra high volume cast iron power steering pump with a 4. 2" aluminum 6-rib serpentine pulley. PumpFeatures:Changeable Flow Valve Technology5, 500 RPM Pump SpeedCompletely New Pump17-Spline Shaft and Nut to Retain PulleyTrue Bolt-on -10 Inlet Fitting80mm Bolt Pattern, Direct Replacement GM Saginaw PumpsEngraved with a Registered Serial Number and LogoDespite the economical price, these pumps are not remanufactured from junkyard cores. They are completely new and have the same dependability, precision machining and changeable flow valves as our aluminum power steering pumps. The standard flow for a cast iron pump is 2. 5 GPM, but can be changed from 1. 5 GPM to 3. 7 GPM depending on the optional flow valve installed. KRC Changeable Flow Valve TechnologyKRC offers the only power steering pump with changeable flow valves, allowing the driver to fine tune the feel and assist in the power steering system. Click here to read more about this exclusive system. KRC cast iron pumps are only available in 13. 5cc ultra high volume. It is designed to take tight spots out of your steering system when using a factory steering box and a 2-to-1 steering quickener, as seen in street stocks and open wheel modifieds. With the high volume of this pump you must use an under drive kit to keep the pump speed below 5, 500 RPM. For high RPM V-belt engines you can use KRC 20102000 water pump drive kit to reduce the power steering pump speed by 42%, which in turn conserves horsepower by the same amount.Pit Stop USA offers KRC 13.5cc Ultra High Volume Cast Iron Power Steering Pump w/ 4.2" 6-Rib Serpentine Pulley 50020000 at low everyday prices. Be sure to check out all of our products from KRC Power Steering including KRC Power Steering Steel Power Steering Pumps.