Heat staining of exhaust pipes

[Maineboy]

This is not my idea but rather one I just found on a Youtube video. Happened across a video of this guy detailing an engine and followed up by looking at his other videos. Looks fairly easy to do with an airbrush.....and a very good eye for detail. a pretty nifty tactic in my book.

exheat2 by Nathan Pitts, on Flickr

Photo is a bit cloudy as it is a screen grab off of a video rather that a still pic. But you can see the idea.  Scroll to about the 6 min mark in this vid and you can see the process he uses plus better views of the result.

https://www.youtube.com/watch?v=ew4NP1Uu004&ab_channel=ScaledDownCustoms