What fuel octane do you use?

[ToxicWolf]

I use 93 in all of our cars ... Even my wife's Prius.  I've been told that higher octain gas improves milage in all cars. 

But does it increase the mileage enough to pay the additional expense of the fuel ?
Btw, on a Graveyard Cars episode when they fired up a '70 dual quad Hemi,  Mark Worman said "Everytime a dual quad Hemi starts, a Prius dies". 

I did a little testing with the Prius.  It was consistently getting 52 mpg with the cheap gas.  Sinced I switched to the higher octain, it has been 56 to 57 mpg. 

[Michael_B767_ATP]

Hi,

I use a mix of five gallons C12 (octane is 108) and the rest REC 90. Stock 440

Mike

[HP_Cuda]

The highest octane I can find!!!

[73440]

Occasionally use VP 110 leaded, smells great , or 91 or 93.

[Racer57]

When you post what octane your using, please post wtf engine your putting it in ?    As far as I know, you have a stock 225 slant six !! 

[71-440]

When you post what octane your using, please post wtf engine your putting it in ?    As far as I know, you have a stock 225 slant six !! 

That right there is funny....LOL....

[HP_Cuda]

What? Doesn't everyone run a 440???

[chargerdon]

You only need as much octane in our NON-Computer controlled cars as is needed to keep it from pinging at the ignition timing we want to run.   Anything beyond that is a WASTE. 

Now in computer controlled cars we never hear pinging because the electronics "listen for it" and retard the ignition timing as needed to prevent pinging.   So, on them SOMETIMES we will get better performance and gas mileage, if, the system was running with retarded ignition to prevent the pinging.   However, simply using the mfg suggested octane (which is usually 87) is normally enough.

To ToxicWolf...you say your Prius went from 52 to 56 mpg by using 93 Octane in your Prius.   

MAN you are pouring money down the drain.   Here in Raleigh the average price yesterday for 87 octane is $2.35 per gallon.   89 Octane costs .30 more, and 93 another 30 bringing it to 2.95 per gallon...   an increase of 60 CENTS for 93 Octane.   Now 56 mpg is a 4 mpg increase over the base 52, so 4/52 = 7.7 % percent increase in fuel economy.   However, you are paying 25% more for your gas...   Sir...you are pouring money down a drain !!   Higher Octane gas when not NEEDED...is simply a waste !!   Only buy the octane needed !!!   Its just that simple !!   

[ToxicWolf]

You only need as much octane in our NON-Computer controlled cars as is needed to keep it from pinging at the ignition timing we want to run.   Anything beyond that is a WASTE. 

Now in computer controlled cars we never hear pinging because the electronics "listen for it" and retard the ignition timing as needed to prevent pinging.   So, on them SOMETIMES we will get better performance and gas mileage, if, the system was running with retarded ignition to prevent the pinging.   However, simply using the mfg suggested octane (which is usually 87) is normally enough.

To ToxicWolf...you say your Prius went from 52 to 56 mpg by using 93 Octane in your Prius.   

MAN you are pouring money down the drain.   Here in Raleigh the average price yesterday for 87 octane is $2.35 per gallon.   89 Octane costs .30 more, and 93 another 30 bringing it to 2.95 per gallon...   an increase of 60 CENTS for 93 Octane.   Now 56 mpg is a 4 mpg increase over the base 52, so 4/52 = 7.7 % percent increase in fuel economy.   However, you are paying 25% more for your gas...   Sir...you are pouring money down a drain !!   Higher Octane gas when not NEEDED...is simply a waste !!   Only buy the octane needed !!!   Its just that simple !!

Yep ... Went back to the cheap stuff   

[cudabob496]

Hi,

I use a mix of five gallons C12 (octane is 108) and the rest REC 90. Stock 440

Mike

108 probably not doing anything for you.

[Lloyd Lind]

116 octane.....91 plus a methanol / water injection system .28 cents a gallon for the extra cost of 20 below windshield washer fluid and the heet gas antifreeze to doctor each gallon.

[BIGSHCLUNK]

I've had times I've alternated between mid grade and premium.... so 89 / 93... never ping. If I plan on an aggressive weekend then 93.   I 've run 110 race gas..... waste of money.... 

[Shane Kelley]

I like to use this stuff for new builds because it smells good. Doesn't stink me and the shop up when I'm dialing in the motor. That pump gas stinks something horrible when you run these camed up cars in a building. 

I also run my gas tank dry and put 5 gallons of this in for winter storage. Usually run the car a couple miles so I know the system is completely flushed out and nothing but pure race fuel in it.  Doesn't spoil like pump gas. It is expensive! Definitely not for the daily driver!

[HP_Cuda]

Why not run the most advance you can and have fun doing it.

Here ya go!

[mopar thunder]

I usually run 91 minimum in the 440HP Charger, my wife runs the same thing but I told her I think it is a waste to run it every time. Her 74' Cuda has a 360 in it but is a low compression engine so I think 89 would be fine. Before my 70' Cuda went on vacation I ran 93 at low boost to drive around town and if  was going to the track or play around I would add enough Boostane to rise it to 103. That's how it was tuned including the water meth injection.