I remember Flap1, Improved climb V1s of 170+ knots in a 737-300 out of Darwin.
That is frightening speeds for Flap one. Are you sure the speed you recalled is correct? It is hard to imagine needing improved climb at the max structural or Flap One second segment climb in the 737-300. Flap One gives you plenty of climb performance exceeding certification limit. Seems that the problem would be brakes max energy limits at V1 of 170 knots.