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E15 and MPG?

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#1
There was some conflicting data on E15 and the Fiesta ST, however, seems like people can run it on the newer models just fine!
What year model started supporting E15?

And how does it affect MPG (same riding conditions)?
I would estimate that E15 works better on turbo cars running hot climates, than any other..
 


zanethan

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#2
As I understand it, you can run up to E50 on the stock fuel system. That being said you won't see any performance benefit without a tune that takes advantage of ethanol content. The higher the ethanol content the worse your MPG will be. I think E30 tuned fiestas generally return high 20s to 30 MPG on the highway.
 


TyphoonFiST

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#3
As I understand it, you can run up to E50 on the stock fuel system. That being said you won't see any performance benefit without a tune that takes advantage of ethanol content. The higher the ethanol content the worse your MPG will be. I think E30 tuned fiestas generally return high 20s to 30 MPG.
I'd say mid 20s to high 20s for fuel economy with blending!


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Ford ST

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#4
Ethanol simply has less energy, and your miles per gallon will suffer. They sell E15 where I live it's only 88 octane, I hope you wouldn't use that.

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TyphoonFiST

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#5
Ethanol simply has less energy, and your miles per gallon will suffer. They sell E15 where I live it's only 88 octane, I hope you wouldn't use that.

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The right way is to have a tune for e85 and 91 or 93 and blend them. Silly guy...anyone else who thinks otherwise is a dumby!


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OP
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Thread Starter #6
Well, from an economic point of view, does it make sense switching for a regular driver?
I get E15 for $2.29/gal over here, while regular costs like $2.69-2.77/gal. That's like a saving of 2 gal per tank.

I thought the fuel cap read no E20-E80, but I could be wrong. I guess it might be OK for a short time, but the fuel is said to deteriorate the fuel lines.

Some mentions have been made that E15 lubricates the top part of the cylinder more, causing the engine to run cooler and smoother?
My butt dyno does feel a slightly higher performance on E15, but it might be placebo.

Ethanol has an octane rating of 113, so i suspect E15 is mixed with 87 octane fuel, giving about a 89 octane rating.
 


Ford ST

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#7
You can run E15 safely, you just have to figure out is it worth the MPG loss. Where I live E15 is $0.10 a gallon cheaper than 87. I run 93 which is $0.60 more than 87 on average.

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ROCKYFiestta

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#8
i tried this on my car with 91 octane @6k ft elevation i got 31.8 mpg combined then i tried theE15 and i got 27.8 combined mpg i do 15 miles each weekday 10 miles country 5 city.
 


ROCKYFiestta

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#9
i havnt done the math the e-15 is going 2.65 a gal here and 91 is at an abysmal 3.45. the price difference is why i wanted to try it out. It honestly felt as if the fuel gauge dropped faster to empty with the e-15
 


OP
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Thread Starter #10
They've changed prices here too.
E15 now is about 10ct/gal cheaper than regular.
It's not really worth the effort anymore.

I still would pump E15 in hot summer weeks, but will probably go regular the rest of the year.
The MPG difference for me is currently too little or negative, from an economic point of view.

Besides, the car runs great on 87 Octane anyway!
 


Jerickson88

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#11
Our 93 here is labeled as e10 at some places. I averaged this week 30mpg and that was stop and go on the interstate
 


Jerickson88

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#12
They've changed prices here too.
E15 now is about 10ct/gal cheaper than regular.
It's not really worth the effort anymore.

I still would pump E15 in hot summer weeks, but will probably go regular the rest of the year.
The MPG difference for me is currently too little or negative, from an economic point of view.

Besides, the car runs great on 87 Octane anyway!
They do, I wonder how I would fair on an off the shelf map. I would be interested in an 87 slot, maybe 12-15psi.
 


Quisp

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#13
They've changed prices here too.
E15 now is about 10ct/gal cheaper than regular.
It's not really worth the effort anymore.

I still would pump E15 in hot summer weeks, but will probably go regular the rest of the year.
The MPG difference for me is currently too little or negative, from an economic point of view.

Besides, the car runs great on 87 Octane anyway!
You won't believe how great they run on 93 and e85 mixed to E30 and tune .
 


ROCKYFiestta

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#14
went to the pump today and was shocked to see at the maverick gas station they were charging 3.15 for both 91 and the e-15 87 blend [:(!] so i just pumped in the 91 and left confused as to how they managed to jack up the price over 50cents on the eblend.
 


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