Years back I had a shop intstall 3" from DP back to Y. Did a ****y job. Both 90* bends had ripples in it. After putting my trans back in I decided to finally fix it. I also decided to weld in my non cat instead of keeping the clamps

It did change the sound a little. I'm sure flow will improve slighlty.

Here is a video of the exhaust after.

Cutout closed, then opened, then closed.

http://www.youtube.com/watch?v=ldtPOJH8XfU