Ok this is an LS1 issue i know. I have many Trans am friends and it is apperent in their cars too does any one know why the exhaust on deceleration does this signature Burble burble pop-pop sound. It got bad on my car when I put my lt and cat back on my car but then I got a throttle body From Mark Shaner in Arlington Tx and it has reduced it alot? why is this? :confused don't get me wrong it sounds neat?