[mustangman65_79]

When I first got my glasspacks, they too were quiet. But after having them on for a year, they got to be very loud! The rumble from my car could be heard for blocks at idle. I could turn anyones head when just slowly driving by. My car was the loudest on base. There is next to no back pressure with them. All they are is one big pipe with baffels around it. U can see straight through them, so u can just imagine what the exhaust does. When running glasspacks and pipes on the end, u get the crackle noise when u rev, or take off quick, without pipes, they are really loud, rumble noise.