What octane do you run?

[odis]

Filled up with 87 today. I will see what happens. If it pings will I hear it? Got almost 15 mpg on the last fill up with 93.

Thanks

Jim

[scooby5121]

It won't ping......

Scooby

[odis]

Good deal, I will let y'all know my mpg after a few tanks on 87 oct.

Jim

[Nitro375]

87 in my GMC

93 in the 68 Mustang

and 93 in wifey's WRX

 

And they are right, running higher octane than needed

is a total waste of funds.

[Chris]

I run 91 in my Sierra, but it is tuned for it plus it is the high compression 6.0 which GM recommends 91+ in

[Prokopchuk_9]

octane level - Diesel

 

[Wintersun]

The octane rating is a measure of the pre-ignition tendencies of the gas mixture going into a hot engine cylinder and burning before ther is a spark at the plug. The gas is burning before the piston reaches the top of the cylinder. The higher the number the less likely pre-ignition will occur and so an engine can be engineered with a higher compression ratio which in turn will produce more power.

 

Honda put lower compression engines in its Honda sedans than in its Accura sedans and the difference in horsepower was less than 5HP which was quite a penalty to be paying 15-20% more at the gas pumps to have 3% more horsepower.

 

Octance rating is not linear. As little as 10% 100 octance fuel with the rest at 90 octane in the fuel tank can produce a 95 octane blend in terms of how the fuel mix behaves inside the engine. I have a Mercedes coupe that was designed for 93 octane gas and if I burn 87 octane regular the MPG is reduced from 26 to 24 or about 7%. The onboard computer automatically adjusts the timing to avoid pre-ignition so the acceleration may be slightly slower but it is hardly noticeable. I alternate fillups of the coupe with low and high octane gas. I can afford to use premium all the time but I hate to throw money away and if I am going to donate it will be to the Salvation Army and not Exxon which is already using my tax money to its benefit in Iraq.

[odis]

I have burned 3 tanks of 87oct. I can't count the first 2 because I was towing some with both tanks. The last tank I was not towing and got 15.05 mpg.... Can not tell the difference between 87 and 93 except when I go get my change when I fill up with 87. Next month I will be towing and going thru a few tanks and will see what happens. She must be breaking in with 8300 miles and mobile 1.

Thanks

Jim

[odis]

octane level - Diesel

 

I tow around 8000 lbs, if I get a bigger camper I will join the diesel team....8) wish I could justify it now.

Jim