For the inside, if it's just black, don't think you need to clean it. If it's carbon build-up, a small wire brush or wire wheel on a Dremel and solvent like injector cleaner or laquer thinner should do the trick.Received my ITR Header today. Do I need to clean the inside of the piping and sand the rust off the manifolds? What can i use to prevent rusting?
For the outside, if you're not concerned about looks, you can leave it alone. Pretty sure the material is "stainless" steel, but the low-grade type that forms a layer of surface rust. Or have it blasted and ceramic coated, ~$150 done professionally, or buy it at autoparts in a spray can. Don't waste your time with hi-temp paint, used to use it on bike expansion chambers, burns off almost immediately.