I've heard good things about this product and how much it increases hrspwr and really wakes up the sound of your exhaust. So i had it installed on my 95 cobra along with FMS shorty headers. I also have a 2 chamber flowmaster exhaust. I cant complain on the performance factor the car pulls much harder now,but The 1st 2weeks the car sounded great, deep and raw sound. but after that my exhaust kind of muffled and seems quieter. Could their be some sort of a clog or carbon build up causing such a severe sound change?????