[pete]

Originally Posted by goat67

Yup pretty standard it is also possible to get a 91 or 92 version without ethanol that is what I run

Originally Posted by Emerikol

Pete, the short answer is yes, that's what we see in most of North America. Denver, CO is a notable exception. The elevation there is roughly 5,300'. There are also some other cities in Colorado that have higher elevation. Because the air there is so much thinner, the gas stations usually have 83, 85, and 87 octane, respectively. In the states, we use the (R+M)/2 method to calculate octane, but I know that's not a universal format. Some countries use the RON/MON method. What octane ratings do you see over there, and what is the calculation method?

I thought they would be higher...
ours are reg 91 & super 95..
we use the RON system..


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