do you have a gt2 or gt? im running challenge sport x-pipe with the gt2, even with secondary race cats and resonators its extremely loud. the moment you take out ur primary its going to be loud no matter what x-pipe you use. if you want something quieter u will have to change muffler.
ESS | Challenge x-pipe | Akrapovic | Stoptech BBK (380/355) |Ohlins R&T | Dinan | Vorsteiner | Downforce USA | Varis Diffuser | Gintani | UUC | BMW Performance | Macht Schnell | Forgestar F14's SDC 19x9.5F 19x11R | 255.35 295.30