What size pipe after the headers?

[clean327]

I just put some OBX LT's on my 5.3 CrewCab. I have a 11" case magnaflow on it now with 2 1/2" pipe coming out of it dumped right before my rear bumper and the factory pipe from my header flange to the muffler. Should I run a 3" pipe out the back? When I am at full throttle and it goes to shift into the next gear it makes this popping glasspack sound. Is it too much pressure for a 2 1/2" pipe. I am just throwing some stuff out there, so help me out here. I am probably going to put a 18" magnaflow on it to calm some of the drone down. So what yall think?

[justy]

2.5 or 3" doesn't matter. You'll still get a popping noise. Only a good muffler is going to mask it some. 3" would be my goal through the muffler and all the way to the rear. Sound bounces pretty good off pavement or tar.

[clean327]

I have a magnaflow and most catbacks are 3" pipe so I figured that the 3" would be better.