Don't worry, 2.75 inch piping outflows what these cars really need anyway. It's kind of like throttle bodies, they don't add any power either because the stock unit easily maxes out incoming air requirements.
'12 Challenger SRT8 Pitch Black 6-speed, stripe delete, all options
-BT catch can, skip shift eliminator, K & N drop in, BB's resonater delete, Jet 180 t-stat, ceramic tint/clear bra
DA 7170 - that's firstname.lastname@example.org corrected!!!