I put GT 500 axle backs on my Boss....2011 single tip units. I also went with an off road X pipe and ditched the side exhausts. Overall, IMHO, the car sounds a whole lot better both inside and out. Before removing the side exhaust...I had 3/4" hole inserts. You can appreciate some rumble and backfire on deceleration but listening to the car on the track......way too quite. With the X pipe you can really hear the motor rev. from the outside...but not to the point of it being obnoxious. There is still some backfiring on deceleration which can easily be heard...it's just not at your side.
Exhaust notes are very personal choices....so take my choice and MHO with a grain of salt.
2013 PW Boss Mustang, Complete suspension upgrade, MGW, Whiteline tranny bushing, Carbotech XP 12 fr. / XP 10's r, Team Dynamics 18"x10" rims with Continental GT-O 305-650x18" slicks, PJ CF cai, FRPP 84.5mm tb, FRPP 47 lb injectors, O/R X pipe, GT 500 axle backs and Tuning by AED.
2011 F 350 CC, SB, 4x4 with modded 6.7 Scorpion PowerStroke
Last edited by Senderofan; 07-21-2014 at 08:34 PM.