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Discussion Starter #1 (Edited)
So I searched the database and didn't find anything about octane/mileage differences. I know vehicles will get a better gas mileage with non-oxy fuel, then the oxy-fuel. I know there is also a difference between winter/summer gas. I am doing my own experimentation with the different oxy-fuel, finances permitting of course. So I am going to post my findings here.

The truck, I have a 2012 F-150 xlt with the towing package. The previous owner had a 5th wheel plate and airshocks installed as well as an aluminum grille put in the air intake to help protect the intercooler. The only thing that I have done to the truck was gap the plugs to .03, btw, that got rid of my WOT sputter. So my truck is pretty much stock. My truck also has 50,000 miles on it. I also have a trip set for long term too, it has been going for almost a year now and I have averaged 16.8 mpg.

I will try and drive like I normally due, not crazy accerleration, but not granny driving either. My main drive consists of a 50/50 drive, 50% stop light, 50% freeway. I also fill up when the light comes on. I apologize for the 1st and 2nd ones, I forgot to write down the gallons used. I live in SE MN.

The octanes I have to experiment with are 87, 89, and 93, oxy-fuel and 91 and 93 non-oxy fuel.

1st. 87 oxy-fuel 17.8 mpg, 554.3 miles

2nd. 91 non-oxy fuel 19.1 mpg, 562 miles, I have a feeling this should have been better, as we used the truck to drive in town a bit more than usual.
 

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Something that is overlooked quite often is the altitude. Depending on your attitude, depends on the minimum octane you want to run. Octane and pre-ignition go hand in hand, so if you are up at say 6000 feet, you don't need to run 87/91. But if your are at sea level, you are more likely to have pre-ignition and want to run the higher octane.

When I lived in Cheyenne WY, 6200' elevation - I had no trouble running 85/87 octane. I moved to Wichita Falls TX (1,000ft) and make sure I run 87 as bare minimum.

Hope this doesn't throw a wrench into your plan.
 
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I run 85 octane exclusively except when I'm towing and then I bump it up to 90 octane which is the highest I can get around here.
 

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Discussion Starter #4
Something that is overlooked quite often is the altitude. Depending on your attitude, depends on the minimum octane you want to run. Octane and pre-ignition go hand in hand, so if you are up at say 6000 feet, you don't need to run 87/91. But if your are at sea level, you are more likely to have pre-ignition and want to run the higher octane.

When I lived in Cheyenne WY, 6200' elevation - I had no trouble running 85/87 octane. I moved to Wichita Falls TX (1,000ft) and make sure I run 87 as bare minimum.

Hope this doesn't throw a wrench into your plan.
I don't think it will throw a wrench in the plans, as I am around sea level or close to it. However, thanks for the heads up.
 

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I have a 2013 XLT. ECO. Sea level. 87 only for the almost 8000 miles on truck. Trip B never reset and I average.16.9 with 50/50 freeway/city on what ever garbage gas California wants to use. It just my thoughts but I dont think using 91 octane gives you enough extra MPG to make it worth using. But I will watch this thread to see what you find.
 

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I have a 2013 XLT. ECO. Sea level. 87 only for the almost 8000 miles on truck. Trip B never reset and I average.16.9 with 50/50 freeway/city on what ever garbage gas California wants to use. It just my thoughts but I dont think using 91 octane gives you enough extra MPG to make it worth using. But I will watch this thread to see what you find.
Maybe not, but the anti knock properties sure make it worth it...
 

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I have tried putting Premium (91 & 94) in a bone stock truck (including stock PCM tuning) and it did not produce any noticeable increases in fuel economy.

However, when I tuned my PCM for higher performance octane from a number of tuners, not only did I get the performance increase, but I often got a small increase in fuel economy (1 or 2 mpgs) on a standard route I take to visit family.

I do have a couple of "economy tunes" but ... I was spoiled by the performance tunes, and quickly ignored them. Maybe others who have specifically ran economy based tunes will have more to say.
 
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I just came home from a trip to the Okanagan from Edmonton and back. Its a little over 1000 km's each way with the first half fairly flat and the other full of lots of long, steep climbs and descents. On the way down, I averaged 14.4 L/100 km's using regular fuel while completely empty. For the return trip, I added roughly 500 - 600 lbs worth of cargo and decided experiment a little and fill up with premium ( I was running on fumes at that point so there was little in the way of blended octane. ) I ended up averaging 13.5 L/ 100 km's. Granted i didn't have the largest load, but it did make a difference using premium fuel. I guess the end result is, IMO, its not worth putting in premium fuel considering the premium price, unless towing or hauling. I know having a heavier load would really reduce the avg L/100 km's, but using regular fuel would probably make it worse in that situation. A fun experiment none the less :)
 

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I just came home from a trip to the Okanagan from Edmonton and back. Its a little over 1000 km's each way with the first half fairly flat and the other full of lots of long, steep climbs and descents. On the way down, I averaged 14.4 L/100 km's using regular fuel while completely empty. For the return trip, I added roughly 500 - 600 lbs worth of cargo and decided experiment a little and fill up with premium ( I was running on fumes at that point so there was little in the way of blended octane. ) I ended up averaging 13.5 L/ 100 km's. Granted i didn't have the largest load, but it did make a difference using premium fuel. I guess the end result is, IMO, its not worth putting in premium fuel considering the premium price, unless towing or hauling. I know having a heavier load would really reduce the avg L/100 km's, but using regular fuel would probably make it worse in that situation. A fun experiment none the less :)
Plus the okanagan has a lower elevation so depending on mountain steepness you would have basically driven downhill to the okanagoa and uphill back. Not much but 300m anyways
 

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Good post. I just returned from a 4800km trip from mb to victoria n back.I ran premium the entire trip. Like stated lots of long steady inclines along the route.I averaged 12.6 liters p 100 kms. With the extended range tank and premium fuel i was impressed with getting over 1000 km per tank in the mountains. :beer:

Sent from my SGH-I747M using Xparent Green Tapatalk 2
 

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The owners manual for my 2014 Eco Boost advises against using 85 octane, even in the mountains. It also suggested using 91 octane in higher elevations when pulling.

Something that is overlooked quite often is the altitude. Depending on your attitude, depends on the minimum octane you want to run. Octane and pre-ignition go hand in hand, so if you are up at say 6000 feet, you don't need to run 87/91. But if your are at sea level, you are more likely to have pre-ignition and want to run the higher octane.

When I lived in Cheyenne WY, 6200' elevation - I had no trouble running 85/87 octane. I moved to Wichita Falls TX (1,000ft) and make sure I run 87 as bare minimum.

Hope this doesn't throw a wrench into your plan.
 

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I've started doing my own testing on fuel. Bought truck with a full tank of whatever they put in it. Guessing the cheapest they could buy. My next 2 tanks I filled with 89 non ethanol, my 04 Ranger loved it, so I figured this new one would too. Then went back to 87 with 10% ethanol, and didn't notice any change at all. Maybe when I get a few more miles I will notice a change with different fuels. For now I'll keep running the 87.
 

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You would have to use the higher octane if you have knock on 87. Don't know if i figured this out right but 30 gal of 87 $4.00= $120. Premium at $4.20 =$126. so the $6 you pay more would have to get you 27 miles farther then 87. to break even ave 18 MPG does that sound right?
 

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Ok I'll bite...

As I understand it, octane levels are designed to combust and make your motor go vroooom based on compression ratios. Higher compression engines will burn higher octane more efficiently based on the chemical make up of the gas... thus why vehicles that recommend 93 will burn 87, but be very sluggish and get poor milage.

Here's my experience: I lived in the Toyo FJC world for a while and built a *****in' one. They take/recommend 93. This topic was discussed at UBER MEGA SUPER length on the FJC forum from probably 2008-2011. We were fortunate enough to have a Chemist for BP on the boards and he gave a hella-complex science answer that basically said what I stated above. You cant escape the chemical science of how the different octane fuels physically burn and create energy.

My FJC would run a solid 2 mpg better on 93 than 87, justifying the cost for me. Others negated that and only ran 87. To each their own, it's your truck and your money buying the gas. That being said, I've never owned a forced induction engine before, and never tuned either, and I'm sure that a multitude of factors will determine which fuel will burn the most completely, read efficiently, in each EB.

I am new to the learning curve of turbos and EB in general, but science is science.

The can is open. I'm already sorry...
 

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I have a 2013 XLT. ECO. Sea level. 87 only for the almost 8000 miles on truck. Trip B never reset and I average.16.9 with 50/50 freeway/city on what ever garbage gas California wants to use. It just my thoughts but I dont think using 91 octane gives you enough extra MPG to make it worth using. But I will watch this thread to see what you find.
I'm right there with you. Sea Level in Southern California and will leave Trip B to monitor the miles between each oil change. 16+ average for me too running 87 Octane. I've seen 20+ on a 500 mile road trip when the truck was new and I was babying it, but when driving it like you want to on long trips I'll usually drag it down into the 18-19 range. I have no plans to try Premium fuel.
 

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I have tried putting Premium (91 & 94) in a bone stock truck (including stock PCM tuning) and it did not produce any noticeable increases in fuel economy.

However, when I tuned my PCM for higher performance octane from a number of tuners, not only did I get the performance increase, but I often got a small increase in fuel economy (1 or 2 mpgs) on a standard route I take to visit family.

I do have a couple of "economy tunes" but ... I was spoiled by the performance tunes, and quickly ignored them. Maybe others who have specifically ran economy based tunes will have more to say.
I have 4 more days to endure my canned tuna. I have had super chips for all most a year and can not say I ever used stock or the gas saving tune yet. Hell I went back to the tow tune, for a few days (had to hall an SUV) and it felt like I was driving a slug with a blown head gaskit.
 

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O and a lot more on topic since the tune it has never seen anything other than 93 with 10% ethanol.
before the tune,I noticed the difference from when I added 93 after using up the dealer gas. my truck will never see anything other than 93 ever again. but for anyone testing, that can monitor boost and timing. you should do a wide open throttle 1-2-3 pull 87 and 93. I promise there will be significant differences. IMO the real question at hand is... is the price difference between 87 and 93, relevant to the increased mileage??? if I had to speculate. I highly doubt the added cost of 93 would negate the added fuel economy.
My 2/100
 
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So I did a proof read after pressing Send,and found what I meant to say is I wanted to post this in the I'm drunk forum:rolleyes:
Let me try again, the added cost of 93 will probably outweigh whatever potential added fuel economy.
 
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