I searched for the last hour and cant really find what i need... I have a 06 Sierra RCSB 5.3 and am ordering PS LT's and off road Y pipe. The collector is 3" to 3" Y correct. I Am going to run one dynomax bullet 23 1/2 in length. I can not make my mind up if i should do 3 inch piping off the y to the bullet and then dumped or 2.5 inch off the Y to the bullet dumped. i need to order the bullet tonight so help me figure out if i should order the 2.5 in and out or 3!!! thanks

 

i forgot to add its pretty much stock 5.3 and do i need to worry about back pressure at all bc with this setup i wont have any prob

 

i would say to do the 3 inch off the y into the bullet and a nice mandrel bent dump about 12-18 inches back from it. the length of pipe after the muffler can be played with (longer or shorter) to your liking because it will change the sound.

 

im running 3inch all the way, corsa tips turned out right before the passenger rear wheel, loud as hell, but i love it, 3 inch FTW

 

I cant comment on either, I have a 4" setup and love it.

Id say 3"