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hi all i have a 03 wrx with a complete decat and has a prodrive back box from what i can gather its 3 " from turbo back and has a silencer after 2nd cat now you would think it would be loud but parked next to my brother inlaws sti which has sports cat on and exactly the same system as mine drowns mine out
are there any removable baffles in the back box or should i have silencer bit removed ????? any ideas