For K20Z3 and most K24 heads (Excluding K24A1). Manufacturer Part NumberUpper Coolant Housing. OE/OEM Part NumberUpper Coolant Housing. 1x Upper Coolant Housing. TypeCoolant Housing. The optional Filler Neck is also available with standard 1.25Ã hose or in 12AN and 16AN sizes and was designed for use with an OEM 92-00 Honda Civic radiator cap.
