Regular Vs Mid Grade Gas = 25mpg-> 31mpg-> 25 Mpg
#1
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Tank 1 = 25 mpg (87 Oct)
Tank 2 = 31 mpg (89 Oct)
Tank 3 = 25 mpg (87 Oct)
Mobil Gas from the same zip code. Can anyone explain such a huge jump ??
Tank 2 = 31 mpg (89 Oct)
Tank 3 = 25 mpg (87 Oct)
Mobil Gas from the same zip code. Can anyone explain such a huge jump ??
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Vehicle: 05 Subaru WRX
The higher octane gas is more stable when compresed. Once ignited by the spark burns a little quicker and more completely. Atleast thats is what has been explained to me by a few folks who work for some of the major gas companies. they were only desk jockies though.
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I noticed about a 4 mpg increase in milage with the Supra too, but it was supposed to be run on premium according to Toyota...so that may explain it paritally but if you think about it......gas with a higher octane should burn better which should in theory mean better milage
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Hmm, that's strange. I've ran all three octane levels at a shell station. I've noticed no change in MPG. The only difference I have noticed was that my car ran a little rougher during idle with Premium.
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Vehicle: 2006 Pontiac GTO
The octane rating doesn't say everything about the fuel. Perhaps the fuel composition of the 89 happened to be better. I think this can differ from one gas station to the other