Quote Originally Posted by snYpz View Post
The increase power from cat back is minimal. The catback on the stock CL9 is optimal. Change your cat, that will give u some more gains. Go either magnaflow or rt cat
To get rid of the hissing, change the flex pipe. It doesnt cost that much. Im waiting for my topspeed header to arrive as well. Im just gonna change the flex pipe straight away to avoid any complications or issues with hissing.
Swap the flex pipe to a 2" x 6" double braided flex pipe as mentioned by Tony.
Im not sure where to source it from. Tried ebay but not much success. Anyone know?
what is the complications or issues with hissing?
is there any other funcation for change the pipe?