Re: 87 vs 91 octane for better mpg?
 

Which version of Octane rating are you using RON, MON, AKI, R/M2? the reason I read through this thread was to find some answer to this question but instead just found bickering over what fuel was better to use on merrit of marketing.

all modern engines include a knock sensor that will retard the timing if you use a fuel that is not got a high enough octane rating, that doesn't mean that you get what the manufacter expected out of the engine. to do that you have to know which octane rating system they were using when they rated the engine and suprise saying Amarican isn't an option, we don't have the world standard and allot of different engines are made in different places.


Just my two cents worth.
HBP