Has anyone heard of this?

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From everything I have read online flex fuel isn't worth it from a cost perspective unless you have a performance setup that actually can use the extra octane and cooling effects of ethanol. Most all street driven ls engines don't. Your mileage will drop enough that the cheaper fuel becomes more expensive and there is no performance gain for our low compression engines.
Figure it out as cost per mile. When you have the 6.2l and have to run premium fuel, the E85 (which is about 105 octane) when over $1 per gallon cheaper but you get 2-3mpg less, may actually be cheaper to run.

Now if you have the 5.3l and run regular unleaded, the less than $0.50 gallon difference it costs isn't worth it.
 

TollKeeper

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Just checked my local prices. Regular gas or Premium, it would be most cost effective to run E-85.

E-85 $2.199
Reg $3.469
Pre $4.119
E-Free $3.719

I get 14.5 MPG on E-15 Regular or Premium, and 16.1 on E-Free
Reg $0.239 per mile
Pre $0.285 per mile
E-Free $0.230 per mile

Now figuring--
On a 35% drop in fuel mileage with E85 on the E15 MPG (14.5) gives me 9.6mpg
E85 $0.230 per mile

On a 30% drop in fuel mileage with E85 on the E15 MPG (14.5) gives me 10.1mpg
E85 $0.217 per mile

So its a wash for me, my E-Free fuel ups, and the E85 fuel ups, would net me almost the same fuel cost, except I would be fueling more often with E85. For the 30%, the savings I would have, I would be spending going to fuel more often.

But there is only one gas station in my entire area that has E-Free, and if I take the Esky on a road trip, the E-85 would be my most cost effective route, at $1.30 price difference.

Having the option for E85 would be nice!
 
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I only see about a 20% drop in mpg when running E85

I know it's supposed to have about 30% less energy, but I don't see 30% less avarage fuel economy. For where and the way I drive, I see 11's on E85, sometimes it dips into the 10's if I'm very heavy right footed. I only see 14's on premium 93. I might see more on road trips while highway cruising, but not on a daily average.
 
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Ilikemtb999

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I only see about a 20% drop in mpg when running E85

I know it's supposed to have about 30% less energy, but I don't see 30% less avarage fuel economy. For where and the way I drive, I see 11's on E85, sometimes it dips into the 10's if I'm very heavy right footed. I only see 14's on premium 93. I might see more on road trips while highway cruising, but not on a daily average.

apples to oranges but our 2010 sees about 15mpg on regular unleaded (e10) and about 12-13mpg on e85. Last time I filled up with e85 it was $1.20 cheaper
 

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