Hello I have a '00 300ex with a fmf exhaust pipe. i dont know what kind of fmf pipe it is because i bought it with the pipe already on it. i took it out today and noticed a rattling noise coming from what sounds like inside the pipe. this rattling only happens when i get the rpm's high. is there anything inside the pipe that would cause this noise? if so where could i find a stock 300ex pipe for cheap, as i do not want to spend $400+ to try to narrow down the possibilities. I talked to a friend that said it could just be vibration, but i have tightened all of the bolts on the exhaust, and this rattling is very annoying. any help/advice is really appreciated. thanks!

 

Something could have come loose inside, like a baffle.
Check ebay..theres stock exhaust on there all the time.

 

The pipe could need repacking. Most after market exhaust system you can take out the spark arrestor, and see inside the pipe, i would check that before i bought another pipe