The stuff you put inside of your pipes to keep them turning colors is a hi-temp grease. Used to get a big load of it, and with a finger, smear it in as far into the exhaust as your finger would allow. Then, get a old cloths-hanger or welding rod, with a small patch of mechanics rag attached, coated with grease, and used this to evenly smear the crap inside of said pipe as far as we could reach.
Then after installation (be sure to wear gloves and remove any fingerprints before startup, cause if theres any prints on those chrome exhausts after startup, they are cooked on there!), fire her up and let her idle, will melt that grease, and burn it onto the inside of the pipe, much like a ceramic coating inside. This, insulated the inside of the pipe, sending he heat on down, allowing it to cool off some. If its gonna turn blue, its gonna do it between the 1st bend and the head.
This was not permanent, everytime we pulled the exhaust, we did this, smoked like hell, stank the place up, but no blueing. Myself, didn't bother me....I'd just sandblast them, and spray on the white VHT. Then I went to wrapping.... before wrapping was cool. It was called self preservation. Those exhausts ate my lunch, they hurt.
I used to work with alot of rims with crappy finishes or chrome peeling, so I painted things black. Funny how trends start, everybody did it to dress up something old and used, now, you gotta pay extra for it now on new stuff.... go figure.
