Diesel do you have a 2012 focus? Other cars may sound different with out the rear main muffler. The reason this works is because the 12's have two mufflers and a resonator.
Dyno numbers: 177hp/163tq
Mods: Steeda Intake, STS Kit, Rear sway bar, Lowering springs, Steeda RMM, Magnaflow catback, SCT Tune
Moderator: Third Generation Ford Focus, DURATEC Ti-VCT GDI Performance Chat & Florida regional section