Everyone gets there .02 here. I have the 4.6 stock exhaust right now. I want the low deep rumble idleing that sounds good when you stomp on it too. I have read about changing y-pipes, Flowmasters, dynomax, ect. I really am doing this for the low end gain and the mileage (every F150s owners dream, the 20mpg mark)

And other than wanting the pipes to come straight out the back I have no other "demands". Some one help me set this up please...