Installing a muffler only on my stock exhust 2004 5.3 ......Magnaflow 12579 3" 5 x11 oval 22" case is what everyone seems to use for a no drone sound ........however I have heard that you will lose a little bottom end torque with this muffler an pn 12279 3" 5x8 22" case is better for low end torque .not sure if these two have dofferent internals or what also expect the 12279 to be louder ......not something I really want

Anybody have any experience withthe 12279 ?

 

12579 will sound good and not be too loud, i have found the end of the tail pipe shape makes a difference in drone.
i put 16740 cat back on mine and it droned.
i didn't like the shape and appearance of the m/f tip so i cut it off ahead of the 90 degree rear elbow and put a swept back tip on it... no more drone.
the 12279 will be louder and shouldn't flow any different than the 12579, same inside just less packing in the smaller case