Newbie Here need help

[Custom muffler]

I'm working on a LS1 in a GTO and need help with the tuning file... I will attach the file with info about vehicle vehicle is rumming bad... Help

T

[TAQuickness]

Welcome to the forum T. When you post up the tune file, it would help to also know the engine modifications and a little about what wrong with it.

[Custom muffler]

Thanks TA