need help with pipes

[wags84]

I have 2010 se that I instilled dual straight pipes on . After instill I lost tons of low end and back pressure plus my fuel mileage droped bad little did I know at the time how titans don't like the open pipes . So what I'm wanting to know is what is the best muffler to help me regain some back pressure but will also allow me to have that deep tone ? I'm running at the moment stock cats 2in pipe true duals into 2 1/2 in pipes into 4in tips I love the sound but can tell it need's it's power back to help push my 33s

[nightowl]

The 2.25 or 2.5 inch into a "y" then 3" single in and out muffler is the best performer from what I have learned. Kinda weird you lost low end with 2" pipe.

[wags84]

mines 2in factory straight into 2.5 in pipe into 3in tips but ya it totally killed it when taking off hell i can put it to the floor and it just sounds like its dieing until it gets up in rpm .