Celica Forums General Discussion General Exhaust Problem

The inside of my exhaust at the tip has a lining of some black crap, can some tell me what it is? Also when i am in first when it is just about to hit the rev limiter i hear a ringing sound sort of from my exhaust just before i hit 2nd gear, any ideas? Thanks If im in the wrong forum i apologize.

the black stuff is carbon its normal

Yeah

word on the carbon