A process for modifying the dyeability of polyamide polymers is disclosed, the process involving the addition of co-fed polyamide flake of the same type of polyamide as the base polyamide with the co-fed flake having a significant effect on the final dyeability. The additive flake comprises high- or low-amine-end polyamide flake which is mixed and melted with the base polyamide to adjust the total number of amine ends in the polymer, thereby controlling the polymer dyeability.