There is still a lot of misunderstanding. Premium allows MBT timing which means its going to use the least amount of fuel and make the most power. I have run midgrade and premium in my car and seen the loss and gain of power and mpg. I have seen in my wifes car the loss of mpg and power but there is no driving style that worked to gain the mpg back. I never said the car would not run on regular but that is the lowest and it is more political than fact that they say run regular. There is a war going on and we are in the middle of it. Oil companies that can't make higher octane cheaply and car manufacturers engineers that are demanding higher octane.OVERSIMPLE clarifications (rule of thumb)
"premium" = self esteem felt with purchase of x.
true value = miles (kilometers) per buck.
the denser the fuel (approx = average molecule size) the further you go per unit volume (gallon) = not greater than 0.5-1% per "octane" (compare consequent price increase)
therefore lowest octane without knock = best value.
alcohol = relatively lower density (but raises octane) "do the math"
combustion: best = predictable "slow" and complete burn allowing maximum useful energy to be extracted
knock = explosion = high speed combustion due to burn caused by fast "(super?)sonic" high pressure wave front progressively igniting mixture.
advertising marketing = extracting maximum bucks for minimum value! while making sucker feel good.LOL!
Using the lowest octane without knock is the best value. Note I didn't say using something above 87 is wrong in a vehicle that states to use a minimum of 87 octane or higher.
This is almost as bad as the great oil debate! :screwy: