j bowl

I don't actually know too much about how the Octane ratings work.

However, I know my basic math and I know that 89 and 93 averaged is 91 Octane which is the gas required by our babies. (My area does not sell 91 Octane. only 93, 89, 87)

With the ever rising gas prices, this is just a thought.

Could I put in 5 gallons of 93 and 5 gallons of 89 to get the 91 octane I need and save a few bucks?

Thanks.

BlueDevil34

Not a clue whether it works, but assuming it does, you'll save less than $1 on every fillup. I wouldn't bother.

Your typical gas station bumps the 87 base price by 10c for 89 and 20c for 93. Even as the prices break $3 a gallon, the 10c/20c price increases for 89 and 93 seem to stay constant. So if half of your 12 gallon fillup is 89 instead of 93, you save 60c, regardless of the total price of gas.

j bowl

actually, there's about a $0.30 difference per gallon for me. that's about $1.50 per fill up. 3 fill-ups per week. (yes 3!) that's $18 a month.

although i'll be probably too lazy to do this, i just wanted to know whether the logistics of the averaging works.

JDogg

Yes, it works.

http://www.leesracing.com/articles/a3.pdf

http://www.osbornauto.com/racing/blend.htm

mad-dog-one

I don't know much about this either, but have seen a series of discussions on this topic that indicate that you would be OK using the 89 octane fuel, as long as you don't do aggressive driving that caused detination of the lower octane fuel. Like I said, I'm no expert on this topic and haven't tried regular in my S, but I've been running my VTEC del sol, that also calls for 91 octane gas, on unleaded regular since 1995 without any problems. Good Luck.

Wisconsin S2k

i was under the idea that gas stations actually only get regular and premium, and when someone buys midgrade, the pumps do the mixing on the spot?


howver, if this is true, it's interesting, because a gas station by me this morning claimed to be out of regular, but still had midgrade.....

aggie

Maybe only premium and regular are delived, but they pre-mix them in a separate tank, then they could theoretically run out of regular and still have mid.

SheDrivesIt

Also, if it is true, as I've heard, that the stations only pay 3 to 4 cents per gallon more for premium, then if I was a station owner, I would be "out" of regular from time to time as well.

SheDrivesIt

BTW, speaking of self mixing fuel, when you have the "standard" $.10 per gallon increase between 87, 89 and 93 like we do around these parts, you get a better deal by rolling your own. A half and half mix of 87 and 93 yields 90 octane for the price of 89 but I suspect we are splitting hairs here.

DJRobNM

Consider this. If the price difference between regular and premium remains the same despite overall price increases, than premium is becoming a better deal all the time.