quote:

Originally posted by ridewv:
I've never seen mid cheaper than premium. These are blended pumps so the station has two tanks; 87 and 93, for 89 it blends maybe 1/3 93 with 2/3 87.

That is exactly the blend ratio.

89 isn't made at the refinery. Instead it's made 1 of 3 ways:

Distribution terminal Sequential (aka splash) Blending - load 1/3 tanker truck compartment with premium and then load 2/3 tanker truck compartment with regular. All done from one loading arm. The risk is that if the loading rack goes down (e.g. ground fault), the tanker truck has to drive over to the pumpback tank and the load has to be sent as slop back to the refinery.

Distribution terminal Proportional Blending - use variable frequency drive pumps and both the premium and regular load at the same time with the exact ratio. If the loading rack goes down the blend is perfect and either cut a ticket for the partial load or top off the compartment. This costs more than sequential blending.

Gas Station Proportional Blending - The tanker truck only deliver premium and regular to gas station's underground storage tanks. However, the gas pumps are sophisticated enough to pump premium and regular into your tank at the exact ratio to make mid-grade. This is relatively new and I'd wager a large sum that old pump you photographed doesn't have this.

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Ego is the anesthesia that deadens the pain of stupidity

DISCLAIMER: These are the author's own personal views and do not represent the views of the author's employer.

Modern gas engines that require premium are usually tuned for higher power with high compression ratios or Turbos. I've been driving Turbo cars since 2002 and they all require premium.

If you put in lower octane fuel they will retard the spark timing and make other adjustments to compensate at the expense of power and sometimes fuel economy.

If you spend the extra money to get the more powerful engine, spend the money to feed it properly. If you don't want to pay for premium, then buy the car with the lesser engine that doesn't need it.

Generally gas stations change their price when they get a new shipment of gas. It's entirely possible they haven't ordered premium in a while and it's priced off of the price they paid for it.

I was at a Racetrack about a month ago... the price for no ethanol regular was less than regular.

I suspected they hadn't gotten another delivery yet and the price was still based on previous tank fill