Gas mileage and Gas Octane
 

well I filled up my car the other day with premium gas.

I usually buy shell and the price for premium somewhere else is the same price as shell's 87 octane.

My car get about 50 more miles per tank with 91 octane than 87 octane.

Will this hurt my car or am I actually seeing better gas mileage?

I know I get a little better performance in higher RPM's and if i get a tuner it will help out alot too.

i didnt notice any better gas mileage when i switched from 87 to 93

i've always heard it's pointless to use anything but 87 in these cars unless they are tuned otherwise.. my car neeeeeds 93 because of the timing.

yea...never heard of a milage difference

for some reason i get better gas mileage....

its like i get the same gas milage with my stupid auto if i push it hard alot to like over 3 grand than i would just babying it letting the auto shift at 2k...i hate auto

If you add 93 octane to a car setup to run on 87 octane without making any tuning modifications it is impossible to see better gas mileage. There is no explanation for this....unless:

1 - The car has an octane sensor and can compensate timing (which it does not).

2 - The car is actually tuned to run on 93 and not 87 (which I don't know).

3 - Your test conditions were not exact.

well i get about 21 mpg for a full tank, which is about 260 miles per tank (when gas light comes on).

So ill gas up on premium with a full tank and see how far i get with a full tank.

Im sure that i get better gas mileage becasue the car might be set up for premium. I got 160+ miles on half tank which is 6.5 gallons.

Keep in mind the only real way to test this out is to place the car on the same load for each full tank which is really hard to do.

I don't bother checking my fuel economy unless I have driving for along distance on the highway assuming the trip is pretty much flat.

I just put 700 miles on my truck. Got 14.5 mpg on the first leg and about 17 mpg on the way back.....same fuel octane and same highway. Air was a lot colder on the way back and was drivign more spirited on the way down. See, how you drive makes a big difference.

I see this on my Saab especially. It is a 2.0 T motor. I can get 35 - 36 mpg on a highway trip or 26 mpg depending how I drive. I only get 15 mpg around town if I am always in the boost.

It's all psychological. I went on the 93 octane sprint for a bit there, got too expensive.

i fgured it only cost me like 2 bucks more a gallon. kinda hard to get too expensive

Well the car doesn't exactly need it, plus my state (at the time, Connecticut) had the highest gas prices in the original 48 states. 87 was about 40 cents cheaper than 93. with a 15.7 gallon tank, thats roughly $6.30 more at the pump. Multiply that by the amount of times I filled up at the pump, (roughly five a month)... thats $31.50.

Thats an additional full tank of gas I just spent for a octane level that didn't do anything towards my gas milage or horsepower. Unless your pony's tuned, its all psychological.

I assume you meant tank... not gallon lol
But yeah, any money you can save is good, especially if you are cool like milos and me and used to live in CT (am now attending college in RI) and had high gas prices...

so ture i can push it so hard all week long and then fill up on friday. but then when i dont push it the next week i still fill up on friday.

so in a way i could just haul ass every week and enjoy it. lol

I like my automatic six-cylinder... :attention_whore: