Maybe a fuelish question?

colliehauler wrote:

Turtle n Peeps wrote:

agesilaus wrote:

oldmattb wrote:
Toyota Echo driving from Houston to Atlanta and back several times, I noticed a drop in mileage from 43 highway to 39 highway. I came to realize it was the alcohol in the gas. In this case, ten percent alcohol reduced mileage by ten percent.

Matt B

That shows the danger of informal testing. You are saying that you got no energy from that 10% ethanol. Other factors like vehicle loading, driving style and wind might also affect the results.

This^^^^^.

With modern engines computers always keep fuel at the best stoichiometry ratio for the fuel.

For gasoline that is 14.7 to 1.
For ethanol it's 9.0 to 1.
For methanol it's 6.2 to 1.
For E85 it's right at 9.5 to 1.

Anytime you mix a fuel with less energy with one that has more energy you will end up with a fuel that get less MPG.

With E10 that is right at 3 to 4% less miles / gallon.

The good thing about E fuels is they will make more power than straight gasoline...........and that makes me :)

So with the higher cost of straight gas over E-10 against 4% gain in mileage it's about no difference money wise?

200 miles with 21 gallons of e-10 =9.52mpg vs .84 more mpg for regular gas or 10.36?

It depends on what the difference in price is.

If you get 10 MPG with E10 you're going to get about 10.3 to 10.5 MPG with straight gasoline. So if you are buying straight gas at around 3% more it will be about a wash. Less and you are golden and making money; more and you are wasting money, and losing power.

Doesn't really matter much anyway. Only a hand full of states and a handful of stations sell straight gasoline anyway.