This paper focuses on inductive invariants in unbounded model checking to improve efficiency and scalability. First of all, it introduces optimized techniques to speedup the computation of inductive invariants, considering both equivalences and implications between pairs of nodes in the logic network. Secondly, it presents a very efficient dynamic procedure, based on an incremental SAT approach, to reduce the set of checked invariants. Finally, it shows how to effectively integrate inductive invariant computations with state-of-the-art model checking procedures. Experiments address different property verification aspects, and specifically consider cases where inductive invariants alone are not sufficient for the final proof.