Originally Posted by amg135i
but the test is not to see how loud your m3 is but in comparison which exhaust set ups are louder. So if all tested under the same situations, should give a good idea which setups are louder, no?
Nah, it's totally different free rev vs load depending the design of the muffler. The delta on the Akrapovic is much more than the Innotech for example. My Eisenmann Sport + Turner Test Pipes was just as loud under load as the Akrapovic but almost 9db quieter on free rev.