my car has some tips installed on my stock mufflers and they are pretty big and nice but i think would look 100x better if they were actually clean. My friend decided to grind on his stock muffler tip with some sand paper or something and it looked really rough and it seemed to have gotten more dirty and nasty than before. any ideas? or should i just leave it?

 

EcoTech Degreaser. Works wonders on exhaust residue. Then, if you want it to bling... use a polishing paste called Flitz.

 

simple green automotive and a scrub brush

 

simple green auto is good stuff!

 

Acid and a light scuff pad, if you dont have access to some acid then

believe it or not Brillo/SOS works wonders. Followed by some polish, such as simichrome.

 

Use Coke, none of the cheap RC ****, and no Vanilla Coke either. Use Classic Coke, always worked for me!!!