Before you order anything sit down with an engine builder and come up with a plan. Maybe stop by your local machine shop and have a talk with them and ask if they’ll mentor you through a build. Sweep the floor for a few days for them and just watch/learn how things go together. Become friends with em. You’ll get a lifetime of knowledge. The last thing you should be thinking about at this point is what exhaust tips to use to poke through the bed. Again to answer your question, no roller cams don’t need added zinc in the oil.