Most gas stations where I live have 90%gas/10% ethanol but a few have 100% gasoline. They are usually around the same price.

I have done some not so scientific testing on the two. Run the gas/ethanol mix for around 1000 miles then run the 100% gas for around the same miles and try to duplicate the driving conditions as best as possible.

I have found that the 100% gasoline netted .5-1 mpg better than the ethanol mix.

I was wondering if anyone has any more scientific comparisons or opinions of the two as to witch one is better for mileage and/or tuning.

 

Ethanol is not as efficient as gasoline, scientific fact.

 

If I had the option of getting 100% gasoline I would get it hands down. 100% gasoline has a stoich ratio of about 14.68, and e10 has a stoich ratio of around 14.2. The more alcohol added to the fuel, the less the air in the AFR, resulting in a higher gasoline consumption.

 

There should only be about a 3% difference, everything else being equal.

 

It takes 1 1/2 the ammount of ethanol to make the same ammount of horsepower as 1 gal of gasoline.

 

My current and previous trucks have seen better mileage (02 5.3 and 01 6.0) by 1-2mpg. I run it all the time because of excessive pinging is this normal or do I have other issues?

 

What are you runnin?
E10 or pure gas?



When i drove the van at my last job i saw a 2mpg difference between e10 and real gas.
Added lucas fuel additive and saw .5mpg more.
With e10 i used lucas ethanol treatment i saw 1.5mpg better.

In my truck, i just run whoever has the cheapest 93 when i go to lunch.

 

Nonnie, is this the stuff you used? Got me thinking about trying it lol.

Safeguard™ Ethanol Fuel Conditioner with Stabilizers : Lucas Oil - Safeguard™ Ethanol Fuel Conditioner with Stabilizers

 

I run 100% to stop the excessive pinging and for better mileage. It would be nice to be able to run e10. Is pinging normal for a bone stock 02?

 

NO