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Fuel type and HP on a Stock ST?

OP
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Thread Starter #21
I have been playing around a bit with some Ethanol mixtures, but so far, my best results come from mixing E15, with 87 octane, in a 50/50% ratio.
I tried running pure E15, tried running 87 octane + 1 (and also with 2) gal of E85, resulting in E15-E25,
But a 50/50 mix (E10-E12)still gives best performance on my stock ST.

The only thing I haven't tried yet, is an entire tank of 91 octane.
I did try 50/50 of 87 oct + 91 oct, but I found it to be about the same as the 50/50 mix of E15+regular fuel.

I'm sure if the engine load was higher, or a bigger turbo was installed, the difference would be much bigger.

But in stock form, you'd probably hit the sweet spot between an E10 and E12 mixture.
 


DEss

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#23
I have been playing around a bit with some Ethanol mixtures, but so far, my best results come from mixing E15, with 87 octane, in a 50/50% ratio.
I tried running pure E15, tried running 87 octane + 1 (and also with 2) gal of E85, resulting in E15-E25,
But a 50/50 mix (E10-E12)still gives best performance on my stock ST.

The only thing I haven't tried yet, is an entire tank of 91 octane.
I did try 50/50 of 87 oct + 91 oct, but I found it to be about the same as the 50/50 mix of E15+regular fuel.

I'm sure if the engine load was higher, or a bigger turbo was installed, the difference would be much bigger.

But in stock form, you'd probably hit the sweet spot between an E10 and E12 mixture.
How are you measuring 'performance?'

DEss
 


Ford ST

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#24
There's no way on this planet that would out perform 93. I have only seen E15 as 88.
People are obsessed this whole E this E that bull crap. The whole purpose of a E30 tune is because of the higher octane, so you can run a more aggressive tune and not go boom. Ethanol has less energy then gasoline I don't get why this is so hard to understand.

Sent from my LG-LS997 using Tapatalk
 


Quisp

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#25
There's no way on this planet that would out perform 93. I have only seen E15 as 88.
People are obsessed this whole E this E that bull crap. The whole purpose of a E30 tune is because of the higher octane, so you can run a more aggressive tune and not go boom. Ethanol has less energy then gasoline I don't get why this is so hard to understand.

Sent from my LG-LS997 using Tapatalk
Prezactly.
 


jeffreylyon

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#26
How are you measuring 'performance?'

DEss
I'm calling BS on any "results" unless they're on a dyno in a climate controlled room. The butt dyno and average MPG on the street over multiple days with multiple temperatures and humidity is less than useless, especially when you want to find a given result, such as a magical blend of different grades of gas provides the perfect combination of price, MPG, and performance.

He's not measuring "performance." He's not measuring anything. He's observing his average MPG over a combination of things under his control: the ratios of various stated fuel blends, things kinda in his control: time of day, driving style, and things completely out of his control: actual fuel blends, weather, traffic, etc.

This is about as scientific as holding a 12" ruler up to the horizon and declaring that the earth is flat.
 


OP
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Thread Starter #28
Did you notice a gas mileage difference of any significance?
My ride is the same every day, averaging about 55 highway miles at about 80MPH, and 15 in road miles of 35-45MPH.
On average, I get a readout of 34 MPG with 87 octane fuel (measured over about 5 tanks of fuel), and 32.7 MPG with E15, and 33MPG with E15+87Oct.
So MPG goes down as Ethanol percentages go up.
Not sure why the complaints.
The dash avg fuel meter would not be considered accurate?
I just go by what it says on the display.

As far as performance, there's just the butt dyno, which can tell minute differences, but is true, it isn't 100% correct.
It just feels quicker off the bat, while pure E15 or just 87 octane fuel, feels a bit slower. And E30 feels noticeably slower!

The MPG losses are almost evened out by the $0.10/gal cheaper E15 over 87 octane, (which is a saving of about $0.50 per tank), while a tank of E12 would offer about 10-12 miles less range (which at 33MPG would translate to roughly $1 more fuel consumption per tank).
...Pay a dollar more, and save half a dollar...
Useless to some, interesting to others.

Anyway, it appears some people do find annoyances when I post my findings here.
I merely post what worked for me.
If anyone wants dyno numbers, feel free to do the test and post the dyno results, to prove or disprove anything.
However, my experience with Forum trolls, is that they're not genuine with the numbers posted either.
So you can either take my word for it, or leave it be.
It works for me, and I'm happy this way.
All I want to do is share my findings.

If you have a different configuration than stock, it might not give the same results for you.
 


me32

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#29
There's no way on this planet that would out perform 93. I have only seen E15 as 88.
People are obsessed this whole E this E that bull crap. The whole purpose of a E30 tune is because of the higher octane, so you can run a more aggressive tune and not go boom. Ethanol has less energy then gasoline I don't get why this is so hard to understand.

Sent from my LG-LS997 using Tapatalk
You also need a tune to take advantage of anything more than E15.
 




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