We just put dual 2.5 inch exhaust on my 98 ram with 5.2 motor last Thursday and all I did was put the existing sensors back in the new pipes. A week later and no codes yet, runs and drives great just like I knew it would. Did the same type of setup to my 99 ram I had back in 2005 and it was same deal, never had any problems with it. I don't see why you'd need simulators.