I have the 6.2 in a 2011 Silverado. Since is has single 4" exhaust -- does anyone know for sure if making it a dual 2.5" with flowmaster 70's will hurt or improve performance?

 

true duals will mess with the rear O2 sensors, been there done that. I did not get to try an "H" pipe before I traded it, that may have fixed the O2 poblem???? on my current truck I had the rear O2's removed from the program in the ECU. hope that helps. and no we do not have enforced emissions in Kansas, the farmers would be bankrupt if we did