I have a 06 duramax and I am looking to open the exhaust up because I have a PPE economy coming. I really dont want to get rid of the cat because I am scared of voiding my warranty and causing problems.
So my question is, how much of a difference will a cat-back make over stock? Am I just wasting my time? I was looking at the 5" system.. Let me know guys, thanks alot.
Also, running the PPE tuner, what else should I do to the truck, I am strictly just trying to get better fuel milegae because 12mpg isn't cutting it. Speed is no worry since I beat all my buddies modded cummins and powerstrokes...
