85 octane vs 87?

I too buy at Foodland

 

I burn nothing but 85 - people worry too much. Octane is simply the resistance to preignition due to compression. At higher altitudes the lack of air pressure effectively reduces the compression ration which reduces the need for higher octane.

You can give the oil companies extra money if you want. Personally, they get enough of my money as it is and I see no reason to piss it away on the snake oil and hype that they, oil companies, put out there.

 

NM 86, 88 & 90 are most common. I have 2 stations in town that offer 87. If I’m out of town & cant get 87, I use 88. I used 86 on the maiden voyage with no ill effects. If dropping in elevation in the tank, don’t use less than 87

 

If you're having difficulty higher altitudes with things like starting issues while using 85 or 86 octane it may to be due to the additive package. Change brands. Other than my Costco fill ups, I stick with name brands. Yes, you generally pay a few cents more, but they often include better additives than the bargain brands.