Anyone here have this set up on the car. I want to know if the cats made it too loud or louder. Also what type of performance did you feel with the cats. I have a motordyne plenum spacer with the new titanium invidia true dual. I will soon install the Crwford hi flow cats and a intake on my Z.....Now if I install this mod would I then need to reflash my car? I was wondering if my car then will be running to lean and need proper A/F mapping...