So i have a true dual exhaust on my 4.6 bird. From the downtubes all the way back is dual 2 1/4 inch pipe. Into 2 flowmasters rear mounted BUT it does have exhaust cut outs just behind the diff pumpkin. Now this set up is fairly loud however when i REALLy get on the gas and it gets above maybe 4000 or so it starts to get quiet. Now from about 1700 to roughly 4000 it's pretty loud but after 4 it really quiets down. Does anyone know what would cause this? Does this happen because theres not enough flow (my pipes are crush bent not mandrel)? Whatever it is i want it gone... Because in my opinion when u floor a car it should get louder not quieter! Thanks for the help!