Okay, im new to the site but not new to cars. I just recently purchased a manual 2004 mustang GT with 62K on it roughly now. The thing im trying to do with my exhaust is experience that crackle when the engine dies down but for some reason cant get it to do anything. Its just bland high revs and bland when it dies down. Its got the rumble just nothing after. The owner before me has deleted the cats and has put on an aftermarket cat-back X-Pipe Magnaflow Dual exhaust system. Is the reason why im not experiencing that low end crackle due to the mufflers still being on the exhaust dampening that effect or is it something totally different? Any help would be appreciated thankyou.