Octane rating vs fuel consumption

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justuspost

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I did an informal test this weekend. I did long (700+) road miles to/from so the road was the same. I ran 87 there and got 14.1. I ran 91 back and got 15.4. The raptor seems to be sensitive to speed. I was getting 16.2 at 65mph but it dropped sharply to 15.4 when I rolled it up to 70. Also, I'm running new Goodyear duratracks on 2011 stock raptor wheels. I have a factory tune, Roush cat back and CAI on a '13 screw.

Personally, I'll probably stick with the 91. Added power and even marginally better mpg, works for me.
 

Harblar

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Hablar wrote: "I never got nasty or attacked anyone in any of my posts."

Yes, I did say that. If only there was a convenient way of showing how you were being a condescending ass before I said that and even more since leading up to my last post. That would be really handy¡

Yes, Harblar, I have tested the two and found no difference. I've done it several times, too. But of course I know that any test without benefit of calibrated test equipment and a closed course isn't a test at all.

I answered your question. Now you answer the question I already asked you - did you read those 4 articles before you responded? Be honest.

Just for fun, here are some entertaining quotations from the good people who designed and built our trucks:

Glad to provide the morning's entertainment for you gents.

BTW, how do you precisely measure the amount of fuel actually used in an owner's fuel economy "test?" At the pump? (snicker)

What do you use to accurately measure mileage driven? The odometer in the dash? That's good. How do you calibrate it?

How do you standardize the test drives so that they are the same in all parameters so that they are not a factor in the "test?"

Obviously you make sure that temperature, humidity and barometric pressure are unchanged from test run to test run. I'd be interested in learning how you do that, please.

Okay, enough snark. These questions simply demonstrate that a seat-of-the-pants owner's 'test" is vastly different from a scientific one. The former produces opinions, the latter produces reliable data.

Smile. Enjoy your morning.

Seriously, that whole post proved you were nothing but an *******, hence my calling you on it. I guess you didn't like being called out on your *********, though, because we then got this...

Harblar wrote, "Ruger, seriously... Explain how I got such vastly different fuel economies on the two different fuel types, then?"
No. The responsibility for reconciling one's personal perceptions with reality lies with the individual. Solve your own anomalies, my friend. I have my own to wrestle with.

Hablar wrote, "No, I didn't read those articles, because none of them were about the Raptor."
And you determined the relevance of four articles without reading them exactly how, sir? The 6.2L isn't a terribly advanced design, and the engine management system is certainly modern but nothing very unique. Any current article about modern vehicles would be mostly if not completely applicable to the Raptor.

So what we have here borders on religion. I can't convince you of one single iota because you won't open your eyes. You can't convince me of anything either, because my honest impression is that you're not sufficiently intellectually disciplined to even do the homework. No hard feelings at all, Hablar, but we're an a final impasse here.

Evidently you missed it, but my "snark" comment was aimed at myself. Not, it should have been obvious, at you.

Peace.

You keep trying to post your so called "snark" to make it look like you're the one taking the high road.

Ruger wrote: "No hard feelings at all..."

Then why the need to be such a **** in the first place?

RDFTS is right... Internet Drama, but I really hate that snide, talking down to people ********* when there was never any reason for it in the first place. So, with that, I'm out.


I think Wilson is right...E30 and **** everything else! ;-)
 

mudblood

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Actually, there will be a difference in fuel economy. When I first got my raptor I tried the three main fuel types we had in the area, 87, 89(10%ethanol), and 91. I kept track of the mileage for each tank (still do, though all I burn is 91 anymore) trying to drive the same type of miles on each one. I also made sure to run 3-4 tanks of the same grade in a row to allow the engine to settle into to it. After 6months it was pretty obvious that I could get an easy 50-60 more miles out of a tank of 91 than I could out of 87. The cost difference between the two was negligible even though a tank of 91 obviously cost more. The 89 was right in between the two others, but I opted to just use 91, as the cost wasn't that much higher and I ended up adding a tune and headers, etc... after that.

In the end, to each their own when it comes to fuel grades, but with everything we do to mod our trucks and how we run them, I can't understand why are people so obsessed with cheaping out on the fuel. Put the high grade in, mash the throttle, and enjoy!



Interesting. I have tried that with multiple octanes and multiple brands. All driven the same road and the same mileage. Never saw as much as 1 MPG difference between octanes or brands. Now all brands were top tier gas but that was the only similar factor. Without CALABRATED EQUIPMENT IT IS ALL A CRAP SHOOT. I expect our foot controls gas mileage much more than anything else.

---------- Post added at 10:44 AM ---------- Previous post was at 10:33 AM ----------

Myth busters 2012 enforces my e-30 is ok.

---------- Post added at 08:49 AM ---------- Previous post was at 08:44 AM ----------

Second article second comment 2011 renforces e-30 is better.

---------- Post added at 08:52 AM ---------- Previous post was at 08:49 AM ----------

No date on 3rd article but would sugjest if you can find e-30 you'd have your chep high octain

---------- Post added at 08:58 AM ---------- Previous post was at 08:52 AM ----------

Last article wtf did you read the comments? Anyhow if you want cheap octain ask for e-30 it's 2.60 a gal right now.


Ain't got none in Atlanta that I can find. :mad:
 
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justuspost

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I don't disagree. And since I added the Roush kit, my foot has been much heavier. However, on this drive, I was on cruise 90%+ of the time at the speed limit. At least for my own mind, the results were telling and solid. I'll be sticking with 91.
 

mudblood

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Ruger, seriously... Explain how I got such vastly different fuel economies on the two different fuel types, then?

No, I didn't read those articles, because none of them were about the Raptor. "Any test without the benefit of calibrated test equipment and a closed course isn't a test at all." And if all that fancy equipment and nice course isn't used in conjunction with the vehicle being discussed, isn't it just as useless?

Did I use the pump to determine how much fuel I was using? Yes. Is it "scientifically" accurate? Probably not, but since I'm paying for whatever the amount on the pump says, what else matters?

Did I use my odometer to determine miles driven? Yes. Is that 100% accurate? Probably not, but its not like fuel type has any bearing on the vehicles odometer. 50 miles on the dash will be 50 miles regardless if it was 87 or 91. So, again, what does that matter?

Despite the inaccuracies in the measurements of my "ametueristic" tests, I'm still willing to bet, had they been measured with proper scientifically calibrated instruments by professionals the difference in their results and mine would still be less than .5 mpg for each. That still leaves 3-4 mpg between 87 and 91 unaccounted for.

Did I test on a closed course in similar atmospheric conditions? Of course not. I tested it in the course of my typical daily driving, because that's all that matters. I don't buy a thousand gallons of gas a year to drive on a closed course. This is also why I say 3-4 tanks per variety to test. After 1200-1500 miles on a single variety one can be relatively assured that the contents of the tank are of a single variety (not blended with the remainder of previous tanks). It also assures that the vehicle will see a wider variety of conditions (weather, road work, a few minutes sitting idle here and there, etc) one is likely to normally encounter with each fuel type.

My "typical" daily drive is 80 some miles of mostly highway driving, anywhere from 55-70mph in 10-15 mile stretches. My "tests" were conducted how I drive, because that's how 99% of the miles on my truck are going to be put there. I tested my truck under real world conditions, being driven in my normal style, over routes that I normally drive. What else matters?

I never did any real tests for in town stop and go driving at 40mph or less. I have to figure that 87 & 91 would be closer to each other in those circumstances. Maybe that's how you tested and maybe that's why there is less than a difference. I don't know.

All in all I'm well aware of the difference between my test and a scientific one, but that "reliable data" really isn't reliable outside of the lab since we tend to spend most of our time driving in conditions that vastly differ from the controlled environment in which your "ideal" tests were performed.

As for your, "snark"...

... Blow it out your scientifically tested tail pipe! I never got nasty or attacked anyone in any of my posts. (Note, disagreeing and posting a counter argument in a discussion is not an attack.) You don't want to use 91? Fine, don't. I don't care what you do, but don't try to tell me I'm full of shit when I can show you an odometer reading, fuel amount, and fuel price for every ounce of gas I've put in my raptor from the word go. I know what my real world obtained data says.

Have a good evening.



If I close my eyes...............it never happened!!! Who gives a rat's ass about logic!!!!:facepalm:

---------- Post added at 10:53 AM ---------- Previous post was at 10:49 AM ----------

Cudos, points and congratulations to Wilson! He does not waiver, his enthusiasm does not wax and wane, his fervor never dims. An excellent American! (Leave us not mention that he has over seventeen thousand posts to his credit here!)

And 16,998 post are about E-30.:snoopfacepalm:
 

Harblar

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I did an informal test this weekend. I did long (700+) road miles to/from so the road was the same. I ran 87 there and got 14.1. I ran 91 back and got 15.4. The raptor seems to be sensitive to speed. I was getting 16.2 at 65mph but it dropped sharply to 15.4 when I rolled it up to 70. Also, I'm running new Goodyear duratracks on 2011 stock raptor wheels. I have a factory tune, Roush cat back and CAI on a '13 screw.

Personally, I'll probably stick with the 91. Added power and even marginally better mpg, works for me.

I've noticed the same thing. 50-65 mph for longer stretches seems to be the sweet spot. I've even seen the average go as high as 18mpg when running 55mph and being über conservative on the throttle and acceleration. (Was Running really low on fuel and had 15 miles to the nearest gas station. Made it with a half gallon or so to spare! Haha)

I also saw the two fuel types start to match up below 40-45mph or so.
I also, and this completely my own opinion, tend to think fuel economy with 87 takes a bigger hit in high head winds and cold weather than it does with 91. (Living in SD we get a lot of driving in wind and cold! Hahaha)

Even if 91 costs more in the end, I don't see it as being significantly more expensive to personally justify the loss of 10 hp. I like my truck to run at peak hp/torque.

*note 91 may not increase peak torque, but it doesn't decrease it either, so, despite what others might infer, on 91 you are indeed running at peak Hp AND peak Torque.
 

mudblood

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I've noticed the same thing. 50-65 mph for longer stretches seems to be the sweet spot. I've even seen the average go as high as 18mpg when running 55mph and being über conservative on the throttle and acceleration. (Was Running really low on fuel and had 15 miles to the nearest gas station. Made it with a half gallon or so to spare! Haha)

I also saw the two fuel types start to match up below 40-45mph or so.
I also, and this completely my own opinion, tend to think fuel economy with 87 takes a bigger hit in high head winds and cold weather than it does with 91. (Living in SD we get a lot of driving in wind and cold! Hahaha)

Even if 91 costs more in the end, I don't see it as being significantly more expensive to personally justify the loss of 10 hp. I like my truck to run at peak hp/torque.

*note 91 may not increase peak torque, but it doesn't decrease it either, so, despite what others might infer, on 91 you are indeed running at peak Hp AND peak Torque.




You run cruise at 50 MPH you will be amazed at the gas mileage improvement. Course you might get a:flipthebird: finger or two from the folks who don't give a crap about gas mileage and are probably running high octane too at 75 MPH!!
 

Harblar

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Interesting. I have tried that with multiple octanes and multiple brands. All driven the same road and the same mileage. Never saw as much as 1 MPG difference between octanes or brands. Now all brands were top tier gas but that was the only similar factor. Without CALABRATED EQUIPMENT IT IS ALL A CRAP SHOOT. I expect our foot controls gas mileage much more than anything else.

---------- Post added at 10:44 AM ---------- Previous post was at 10:33 AM ----------




Ain't got none in Atlanta that I can find. :mad:

You're not wrong about the foot. That's why I was suggesting to run a single type of fuel after an oil change and a different after the next oil change. The more miles, days, and conditions present during a "testing" cycle will help balance out the inaccuracies and give you a more accurate idea of where your average is on a normal day.

Calibrated equipment is all well and good, but not something the average driver can afford or has access to on a daily basis. At the end of the year, the only data that matters is the total amount spent on fuel divided by the total miles driven on said fuel. In all my personal testing (daily driving/record keeping), the cost per mile of 87, 89, 91 are all within a nickel of each other, so I choose to use what gives me the best HP.

---------- Post added at 10:25 AM ---------- Previous post was at 10:21 AM ----------

You run cruise at 50 MPH you will be amazed at the gas mileage improvement. Course you might get a:flipthebird: finger or two from the folks who don't give a crap about gas mileage and are probably running high octane too at 75 MPH!!

No love from the lead foots. No love from Prius drivers. You can't win so you might as well just enjoy it and not sweat the fuel bill. ;-)
 

Wilson

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Ethanol wrecked my tire









So much power keeps peeling out


I love how ppl cheap out and buy 87 for there 50,000 truck but probably have to add additives to clean it out. Look into it blending ethanol to make 85 octain work that's not ethanols fault! Nothing wrong with adding ethanol to good 91 octain gas to make it 93 because you are starting with good gas! I chose e-30 because I can
If your pissed because I can fill my tank with 95 octain for under $3 a gallon start asking for blender pumps.
 

Harblar

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Ethanol wrecked my tire









So much power keeps peeling out


I love how ppl cheap out and buy 87 for there 50,000 truck but probably have to add additives to clean it out. Look into it blending ethanol to make 85 octain work that's not ethanols fault! Nothing wrong with adding ethanol to good 91 octain gas to make it 93 because you are starting with good gas! I chose e-30 because I can
If your pissed because I can fill my tank with 95 octain for under $3 a gallon start asking for blender pumps.

Dammit, you're going to convert me yet! Hahaha ;-)

Just crossed the 30k mark, what have I got to lose? Worst case scenario, the motor blows up and I have to go talk to Livernois about dropping in a 6.6 super charged monster to replace it.... Poor me. Hahaha =D
 
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