Mine is open and has been for nearly 2 months with nothing but 3" straight out the back. I have people ask me all the time why mine truck sounds the way that it does and I just tell them. .
Rick
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RICK
97 2500,CC,5 SPEED, 3. 54 Limited Slip,Psychotty System,K&N, Pre-Turbo ISSPRO 3" Pyrometer & Boost Guage,Silencer Ring Removed
12,000 RBW 5th Wheel Hitch,25' Excel 5th Wheel,Rancho RSX17000 Shocks,Amsoil Dealer,Straight Piped