| i have a RBP and love it. i started witha cat-back and it was a little louder not much. then i moved to the turbo-bac and that made a huge difference in sound(louder).
__________________ 2006 LLY with some miles
-EFI Live(Best Investment Ever!!!!)
-Turbo-Back RBP 4" with no muffler and my cat ran away 
-limo tinted windows all the way around except winsheild
-18"MKW M25 with 285/65/R18 Toyo A/T
-Afe replacement filter
-Cogneto Leveling Kit |