use mothers mag and aluminum paste polish and a rag... wipe it on, and buff it out... it'll dissolve all that road tar on your tips and make them look better than new... i used it on the stockers and it worked great, now i use it on my 3" mac ss tips and it keeps em nice... on a side note, do any of you have discoloration on their tips? mine are starting to turn on the edge of the tip safter a couple of years with the o/r/ H... it just gets so hot i would burn mysle fon the tips whereas stock they were plenty cool