a buddy of mine that is into hot rods told me about this product that he coated his headers with 8 years ago and they haven't turned color or rusted yet. it is called POR(paint over rust). they have high temp and regular temp coatings. they are kinda high, but worth the money. a 1/2 pint of the high temp will coat about two or three exhaust systems. http://www.prp-porstore.com/faqhtpc.html