im currently using r18 on my 06 charger 5.7 and im pretty happy,i did like r16a more but i cant go back to it,should i go to r20 or should i just keep what i have,i keep hearing bad things about r20 with the 07 5.7 charger but i havent heard anything about the 06's so i dont know what to do...should ...

I LIVE IN CALIFORNIA AND I WOULD REALLY APPRECIATE IF SOMEBODY COULD ANSWER 2 QUESTIONS FOR ME. 1- I HAVE A 2006 CHARGER R/T I HAVE A CAI,EXHAUST,HEADERS,180 T-STAT. I TUNED IT WITH THE 91 CAI TUNE,HERE IN CALI WE ONLY HAVE 87,89,91 OCTANE I USE 91 SHOULD I TUNE IT WITH THE 91 CAI TUNE OR 93 CAI ...