I know a 4" from headers back would be best but I want 2 pipes coming out the back. What if I did a 4" from LTs through muffler then a y pipe with two 2.5" pipes coming out the back. would it defeat the purpose. Not sure if I want to do it this way or just do 3" duals.

 

dual 3s all the way or dual 3s into single 4....

 

3" pipe will not fit between axle and frame on drivers side. if I did 3" duals they would both have to be all on pass side.

 

I have dual 3 inch pipes on my truck run down the pass side with an xpipe and it sounds really good. A lot of people come up and tell me its the loudest and best sounding exhaust they ever heard. I set my exhaust up to compliment a supercharger. Just a thought.