Sup fellow G35 drivers. Does anyone else put in 89 or 87 into their G35 2007? I have a 2007 G35x and I mix it up with 89 or (91 or 93), but I have decided to stick with 89 from now on, since I believe the G35x will compensate for the octane difference and knocking will not happen. Maybe when the G35x is good I will treat it with 91. What do you guys think? By the way, i get better gas mileage with the 89. Around 22 MPG doing about 70-80 in a 60 mile commute daily.

 

Numerous threads on octane. Just search for them, I think you will find your answer and a whole lot more information.

I think the majority of the census around here is why go lower than 91 or 93 when it comes out to be only about $3-4 more dollars at the pump. If the manual says premium is recommended, then i'm sure theres a reason for it.