Where the standard MGA with pushrod engine originally had a Cellular Film Core radiator, the MGA Twin Cam (and "Deluxe" cars) used Flat Tube And Fin Core radiator (more like the later production MGB cars). The overall configuration is unique to the Twin Cam with hose connection pipes on opposite corners from the pushrod cars, and no filler neck.

Also see Engineering Technical Data, MGA Twin Cam, Radiator