Hey guys, I need some help here. I have a 99 cobra vert., 4 months ago i put on a slp loudmouth 1 exhaust and a pypes stainless steel off road x-pipe. Now when i start it, it sounds great. But as i start driving at about 2200-3100 rpm's it make a winding type noise, almost like a import exhaust, but before 2200 and after 3100 rpm it sounds mean. I first thought maybe the exhaust has to break in but i have put about 500 miles on it and it still does it, does anyone know why it sounds like this, is it the x-pipe? or slp? or is there any fix for this kind of thing? Any help would be greatly appreciated. Thanks