Powder coating lasts a long time on most metal surfaces. Longer than paint, but I don't think you can powder coat headers with out having it melt away. The powder coating itself is like a gel that is baked at around 350-450 degrees to cure it. Headers get hotter than that and would cause the powder coat to soften and run and pick up road debris.
As for chrome, I have seen chrome exhausts on things like motorcycles. Usually the chrome discolors under the heat changes on the hotter areas of pipe. I would think the header area would discolor alot. The muffler would probably be cooler and not discolor too much.
how long does ceremic powder coating last?? lets say on headers? is it worth it? does it even help with heat??
and will the chrome on the headers fade away? will it take years or months for both chrome and powder coat? thanks.....