If you get no air flow, try making plates (with plastic, aluminium, fibre whatever) that go between the FMIC and radiator to force the air to go through the radiator. That would be my suggestion with a stock radiator or with an upgraded one.
JustJap sell fat radiators for cheap. Cheaper than anywhere else. too_much_boost runs one in his cef I think and he reckons it's the goods (good enough recommendation for me!)
GOod luck