Does an LLC that has elected to be taxed as a corporation need articles and bylaws?

The tax classification is just that, a tax classification. The formalities of the entity are handled under state LLC statutes. LLCs are incredibly flexible, but you would not generally convert the Certificate of Formation (or whatever it is called in your state) to Articles or Incorporation. By Laws are just a way of governing the entity and you can usually call them whatever you want for an LLC. However, keep in mind that some states strictly require Operating Agreements for the LLC, otherwise you are governed under the basic LLC statutes rules.