ARP 5/16-24 X 4.500 SS Hex Water Pump Pulley w/ 3.250in Fan Spacer Stud Kit ARP Sale! from 3099 /per Qty. Add to Cart This item is either made to order or has limited inventory. Please reach out to confirm lead times if needed. ARP 5/16-24 X 4.500 SS Hex Water Pump Pulley w/ 3.250in Fan Spacer Stud Kit