Toptiergas.com. good read with stations that are top tier certified.
Pure-gas.org is where you will find ethanol free gas.
You can google about the octane ratings and why you shouldn't use premium unless stated on your vehicle.
Basically I kinda told you what you needed to know, i just...
I live in colorado and 85 is the regular here. Mid grade is 87. Running 85 will work but just like the manufacturer recommends 87 you run 87. 89 is fine but 91 and up you will not gain anything besides draining your wallet. Your best bet is 87 ethanol free aka clear gas. But need to also use...
Oops, I'm not liking the shifting, also can feel it downshift when I'm coming to a stop and sometimes will get a slight clunk in the rear also downshifting.