ok if i bore out my intake manifold and get bigger valves and ported polished and a 3angle do i have to get tuned or can i just run with the factory tune i have a 2.2 cobalt 2005

 

You don't bore out a plastic manifold. You don't get bigger valves unless you are repairing a damaged valve seat. It sounds like you want to do a Port and Polish job on your head. To answer your question, you don't need a new tune to run a performance head. By the way, removing your head is a major job. If you are doing it, you should be considering a larger picture.