Octane rating vs fuel consumption

Myth busters: Consumer Reports takes on alleged gas-saving tips - CSMonitor.com

Will higher octane fuel improve gas mileage? - Motor Vehicle Maintenance & Repair Stack Exchange

Does premium gasoline get better mileage? - Ask.cars.com

Will a Higher Octane Level Increase a Car's Fuel Mileage? - CarsDirect

These articles make the distinction between whether premium fuel is recommended or whether it is required for the specific vehicle. If the manufacturer says premium fuel is required, then the vehicle will probably get slightly poorer fuel economy if run on regular gas. If the manufacturer says premium fuel is recommended but not required, then there probably will be no difference in fuel economy.

Ford neither requires nor recommends premium fuel for our engines. On page 392 of the 2011 Owner's Guide for F150 trucks, under the heading of Maintenance and Specifications, and under the subheading of Octane Recommendations, it says this:

3.7L V6 / 5.0L V8 / 6.2L V8 Engines
Your vehicle will run normally on 87 octane regular fuel. Premium fuel will provide improved performance.

MTF said:

The thing to remember is they only make two different octanes, crap low octane and premium everything in between is blended.

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This is 100% true. Every oil company makes regular and premium in base form only with no additives. These two grades are then bough/sold and traded between them to fill various contracts and such. So BP gas goes to Exxon, Exxon gas goes to Shell, you get the idea. The additives are then added at the truck terminal before it goes to the stations. The difference in price is mostly basd on the additave package.

I've worked in the oil transport industry for a while now. The good stuff is the aviation gasoline, 118 Leaded and a pretty blue color!

I've run my truck on 93 for a bit, with a tune, and got around .5 to 1 mpg better. Based on the price spread I don't think that it worth it $$$ wise.

Without a tune I don't think running on premium is really worth it.

Harblar said:

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!

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Ditto. This was my findings also. It does run better and longer with premium.

i saw a slight difference using non ethanol rec 90 vs. e10 93 oct. the rec 90 got about 2 mpg more but felt like a pig the whole time

E-30 rocks

Ruger said:

These articles make the distinction between whether premium fuel is recommended or whether it is required for the specific vehicle.

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I don't think anyone was saying that Premium was required for the Raptor. Only said peak(advertised) HP/Torque was achieved through the use of Premium. This is a fact and also stated in the owners manual.

If the manufacturer says premium fuel is required, then the vehicle will probably get slightly poorer fuel economy if run on regular gas. If the manufacturer says premium fuel is recommended but not required, then there probably will be no difference in fuel economy.

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Yet mine and others have tested and demonstrated that premium does improve fuel economy on a stock Raptor. Enough to offset the higher price per tank of the premium versus regular. I'm not doubting your links, but unless they are testing a Raptor, with it's modern fuel injection and metering system, (which will adjust the fuel/air mixture automatically as needed based on octane and air density in order to provide the best possible mixture to the engine) then their findings are pretty subjective and not really relevant to this particular discussion.

Ford neither requires nor recommends premium fuel for our engines. On page 392 of the 2011 Owner's Guide for F150 trucks, under the heading of Maintenance and Specifications, and under the subheading of Octane Recommendations, it says this:

3.7L V6 / 5.0L V8 / 6.2L V8 Engines
Your vehicle will run normally on 87 octane regular fuel. Premium fuel will provide improved performance.

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So what? It's just saying that any regularly available standard fuel type (87, 91, 93) is safe to use with those engines. It also says that Premium will provide improved performance. So, yeah, it doesn't say "recommended", but I, for one, think improved performance is probably a good thing and take that to mean recommended.

Again... It just amazes me people still want to argue in favor of 87. Unless there is no premium available anywhere close to you, there really isn't any good/valid reason to be running 87 in your Raptor. Don't believe me on the fuel economy? Try it yourself. It really isn't going to cost you anything. Run 3-4 tanks of 87 and then run 3-4 tanks of 91/93. Try to drive the same type of miles and with the same driving style (same acceleration habits, braking, idle time, etc...). I guarantee you'll see a noticeable difference between the two fuel types.

Have you tryEd e-30? ^

The Macf said:

Non US countries use RON. Your 98 is our 93 octane. Use that.

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Holy ****! Ive used a 93 tune with of 95 non US rated gas ONCE because that gas station didn't have 98 at the time, thinking it'll be fine, guess I was wrong... thanks for the clarification.

So our gas rating goes like this if I understood right:
US 93 = 98 RON
US 91 = 95 RON
US 89 = 93 RON
US 87 = 91 RON

Correct me if Im wrong.

Harblar, did you read those four articles?
Just askin', because I went to the trouble to provide articles from four different sources, they all came to the same conclusions, and it was quite clear that their frame of reference was vehicles with modern engine and fuel management systems.

BTW, the Ford manual makes it clear that peak torque is unchanged regardless of fuel.

Myth busters 2012 enforces my e-30 is ok.

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

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

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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.