All of my vehicles get better gas mileage with non ethanol gasoline without question. I run 93 non ethanol in my GT (which has a Steeda 93 tune). Has anyone done any dyno testing between the ethanol vs non ethanol gas in our cars whether it's 87 or 93?

 

not hard to guess the difference. According to google, The energy content of 1.0 US gallon of ethanol is 76,100 BTU, compared to 114,100 BTU for gasoline.

So ethanol provides about 67% energy as gasoline. 10% ethanol would be energy of 96.6% of 100% gasoline.

So you'd see 3-4% loss in power.

 

I know if you tune your car for E85 people are seeing a 10rwhp gain over the 93 tune.

 

Hes not talking about E85, you get more hp on E85 because the 105 octane level allows for more timing, hes talking 87-93 octane on E10 were you cannot up timing since regardless of ratio of gas and ethanol its still only 87-93 octane.

Edit also, E85 allows for much more than a 10rwhp gain.

 

I thought i seen most 93 octane tune dyno at around 10-15 peak rwhp gain and E85 around 20-25 peak rwhp gain.

 

Think you are missing the point. An Octane rating is the resistance to burn. Higher octane is higher resistance allowing for more timing for to allow for that longer burn to give more hp.

Regardless of pure gasonline or mix they have they are both 93 octane so you wouldn't safly be able to up the timing further. Since gasoline has larger energy output it makes more power with same length of burn.

The factory car is always very conservative tune wise due to manufactures taking into account stupid people that will put bad gas in and drive 6th gear up a hill at 45mph, and putting massive load on the engine and they don't want to pay for warrenty work so they make them semi stupid proof. So in that regard you definatly see a increase for a tune, by making it ideal for 93 octane.

Using a Terminator like mine for example usually sees about 10rwhp for every degree of timing increase. On E85 they usually can up the timing 5-6 degrees giving a 50-60rwhp increase over E10 93 octane.

Again, if you could get pure gasoline at a 105oct rating it would make more power than the Ethanol due to the energy content of gasoline being higher.

My explanation isn't perfect but I hope that clears up some stuff.

 

Good explanation.

 

So 45 mph uphill in 6th gear on bad gas is bad? So that's what I've been doing wrong.