Its not really to much louder. You can tell a bit of difference though. I have the limited pipe in both of my blasters and one has the factory W/B still in it. When the hoods are up you can deffinitly tell a difference in sound but its not bad at all. To be quite honest I don't know/could'nt really feel, that it makes a huge amount of difference, Im sure it helps out a little though. except that your not as likely to blow the Factory Pipe Aluminum Box apart, like the fiberglass factory one.