An effective model for QED with the addition of a nonminimal coupling with a chiral character is investigated. This term, which is proportional to a fixed 4-vector $b_mu$, violates Lorentz symmetry and may originate a CPT-even Lorentz breaking term in the photon sector. It is shown that this Lorentz breaking CPT-even term is generated and that,in addition, the chiral nonminimal coupling requires this term is present from the beginning. The nonrenormalizability of the model is invoked in the discussion of this fact and the result is confronted with the one from a model with a Lorentz-violating nonminimal coupling without chirality.