please help somebody, anybody

[moyer]

i have a 94 integra sedan. the only thing i did was put on a greddy sp2 cat back exhaust. here's the problem. when it rains, and only when it rains, the exhaust bangs violently against the area it resides in close to the center of the car. this tends to be the worst at about 4.5 rpms or higher. i called greddy they have no idea. the car idles fine. no one is able to give me an explaination. i joined this site in hopes some one can help. i'm so pissed im ready to go back to stock.

 

[eg6sir]

did you attach the hangars so the center section doesnt wobble around

 

[moyer]

thanks

all hangers properly secured. cat cover is tight. like i said, real weird, it only happens when it rains. it is so bad my drivers seat shakes. could it be the cat is bad. it is kind of old. i don't understand why the rain would do this. the exhaust is stainless