warp0007

I just recently replaced my clutch. Had to take the exhaust off to take tranny off. Well the exhaust bolts and the whole system was just so rusted and old I decided that since eventually im going to get a nice high performance exhaust system that I would just leave it off. So all that is there is the downpipe cat. Like its the stock downpipe seems to have cat converter material inside of it. Yeah it smokes, yes it lkind of back fires or makes like little popping noises when you let off the gas. Is this bad for the engine?? i didnt notice a performace incresae or decrease to tell you the truth./