is this bad????

since i have done my exhaust about a year ago. (headers, cat back, and pretty much a test pipe) my exhaust seems to have no back pressure. it will make a back fire like noise when i push my clutch in at certain rpm's and now i have this rattle i cannot get rid of. i think the rattle is coming from the exhaust sounds inside the pipe as it is traveling through the pipe and out. some wierd thing with sound waves. and, since i don't have a cat to give it some back pressure i think this is causing me some probs. i have tried many different things but putting the cat back on(which i don't have anymore) to help rid me of this horrible rattling sound. but is my set up hurting my exhaust valves and causing this rattle? any advice would help. thnx

Are you sure one of the hangers isn't touching metal. I know this doesn't account for the loss of back pressure and backfireing, but it might help.

Which exhaust did you put on your car?
Have you done any other mods to the motor?
How big/small is this exhaust?
Did you install it in your driveway or did you have a garage do it?


These are questions that if answered, will greatly increase the odds of getting a correct response from some of the more experienced people around here.

i did it all myself. it is 2 1/4 inch cat back piping. i'll check the hangers.
and all my mods are in my sig.