i got custom piping a few weeks ago and after i rewelded the resonator back on, it pushed my muffler outwards a little, so that the inside part of the rear bumper might have contact with a part of the muffler tip. today i rinsed my muffler for fun with a hose and i noticed that portions of my rear bumper has melted onto the muffler tip. it's not noticeable until you get REALLY close up and take a look.

I'm taking it back to the shop next week to get it fixed, they should fix it at no additional charge, right? because they didn't do that well a job the first time around...

im also thinking about putting a rear lip on, but with this experience, i'm thinking that the muffler might melt the lip if i get one? how much space between the muffler tip and the rear bumper/lip is ideal? i like the idea of my exhaust tip tucked and flush with my rear bumper, with as little space as possible... i'm thinking that as long there is no physical contact between them, i can put them together safely with say, 1-2cm clearance?