Normaly quite noisy yes, but i guess depending on the muffler will make a difference, I have a 2.5" catback with 2 mufflers which makes it almost as quite as orignial but with a much deeper grone, the highflow cat and pacemaker extractors kinda help that to (yeah i understand the stupid idea of having good extractors and cat and 2.5" with 2 restricting mufflers but it gave me a boost in engine performance and the much sort after engine note so i was happy)