questions about 05 lly tunes

[texbiggear]

2005 gmc 2500 hd k & n cai

currently running 80 hp tune wondering if i need to get bigger exhaust for truck if want to run 120 hp tune. not going to run quarter miles just want best mpg. yes i can keep foot out of it unless i need to pass. new to forum lots of info. thanks for any help.

[mikel]

No need for exhaust upgrade if you want to run the tune seeking MPGs

I run the 120 tune in our LLY all the time, its bone stock