i recently got my obx catback installed and for some odd reason it sounds really bad when i start it after the car has been overnight or a long period of time (hours) ...but after i drive it till the car warms up and shut off the car to restart it ...the horrible sound is gone....i have no clue what is goin on....

 

what's it sound like?

 

it kinda soudns like metal is hitting on metal....kinda like a tinging noise....

 

I had a similar problem....it turned out being that the b-pipe was hitting the metal bar that bolts up underneith it toward the middle of the car. If you look under the car, i'd say around the hump between the front seats, you should be able to see this small bar that I'm talking about. See if your exhaust is hitting it. If so, you can pull it up using a 3" hose clamp around the rubber exhaust hanger in the middle.

 

thanks man....ill check on it tomrw...im not sure if thats the problem but we'll find out

 

it mite also be your b-pipe banging on your headshield....