I know the subject has been discussed over and over, but as a brand new owner who lives at 8000’, I have a question. 2017 CX 5 GS, the manual says burn regular fuel but also says 87 octane. At our elevation, regular is 85 octane, and 87 would be mid-grade. Even when we travel down to 4 or 5000', about as low as I ever drive, regular is 86 octane. My understanding is that because of the lower air pressure at these elevations, the octane ratings are adjusted down.
I've only had the car a couple of weeks, but it seems to be running very well on regular (85), and getting over 30mpg in mixed driving, even up and down the mountains. It seems happy, and it can't be overly retarded and running that well (I think), but I certainly don’t want to damage the engine either.
I guess I'm just having a hard time wrapping my head around a 13:1 compression engine burning regular fuel.
What do you think, at these elevations is 85 octane appropriate?
thanks
I've only had the car a couple of weeks, but it seems to be running very well on regular (85), and getting over 30mpg in mixed driving, even up and down the mountains. It seems happy, and it can't be overly retarded and running that well (I think), but I certainly don’t want to damage the engine either.
I guess I'm just having a hard time wrapping my head around a 13:1 compression engine burning regular fuel.
What do you think, at these elevations is 85 octane appropriate?
thanks
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