I've been using 91 & 89, as kind if a blind, since i never let the tank get less than a 1/2 tank, i swich from one to the other every fill up. But lately ive been getting just 89 or 87 and wow have I see nthe diffrence! The hemi gets worse gas mileage with87and dosn't seem as peppy.

 

reset the pcm next time you fill up on 87 or 89. id bet it just needs to get used to it.

 

94 or 93 only with hypertech max energy.