My manual say to use 87 octane (or higher),I have been told the higher the octane the better it burns which makes the motor run better and less sluggish.I duno for sure but i use 93 octane anyway,to me a few pennies is no big deal.and its a good thing there are inline filters on the fuel pumps and on my vehicles cause i would run out of fuel if i didn't fuel up when the stations are getting fresh fuel,seems like there always getting new fuel lol.