It must be remembered that any thrust achieved from an efficient radiator design first has to overcome the drag of the cooling system itself, if you can do that then your on a winner and i’me not sure any design has actually done that. The French Morane MS.406, as an example, had a retractable radiator(as do Hawker biplanes) which needed to be fully wound out into the airstream when high power was being used, consequently in a climb or during combat you had the highest possible drag situation. So just when you needed maximum performance your aircraft was handicapped by its cooling system design.

Richard