i live here in Oregon. we have 92 here, but we get our tanks filled by someone that workd at the station.
Depending on how much they filled my gas tank:
I get bout 260-280 on city driving, and about 300-315 on highway.
my car has only a cold air intake with 33000 miles. I used to put this Fuel additive, it suppose to increment your octane from 87 to 92, but I think that screwed my car up a little. cause when I floor my gas pedal, it feels like the gas cuts off or something like that, and the boost goes all the way to 11 psi. anyway something got screwed up and now I need to fix it. thx.