Hi just wanted to know if i had a mk 1 manifold on a mk 2 and a decat centre pipe but just a standard backbox would i gain anythink regarding noise, cuz i dont want a new backbox cuz its brand new but wanted to get a lil bit of noise gain, my mate has a 2.5inch saxsport and thats stupidly loud i no i wudnt get the same really but i was just wondering if i would get nyfin or nt?