My exhaust has a titanium tip on it. As time has passed it is no longer the color it was when new, now its just black and ugly. I was wondering what I could use to clean it.
here is a pic of what it used to look like...

and here is what it looks like now

sorry for the dirty car in the pics

 

I use Mothers Chrome and Mag polish on the muffler tips of my IS 350 all the time. Makes em look pretty damn sweet.

That looks like some pretty caked on grime though. You might want to start by washing it, then claying it before moving onto polishing.

 

clean it with some degreaser...then get some brassoooooo or metal polish on it maybe...