Octane rating

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drokmofo

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I ran 91 for 10+ yrs until gas prices went too stupid a few yrs ago. I think that running higher octane has its benefits and drawbacks. I think it burns a little better with better combustion. I have had people tell me they get 1-3 more mpg with higher octane here in the sw. Is the cost worth it? I havent done the math. I have run 91 in my '96 fullsize chevy for most of its life and have 318,000 original miles on it. I haul hundreds of lbs of saltwater and freshwater in it daily to maintain my aquarium customers. After the most recent gas price spike the difference in price between reg and prem has been around .40 here. Prior to the last spike the difference was about .20 between the 2 grades. Costco has best prices and top tier fuel. We put in our own additive @5x what the EPA mandates. Gas is gas. The additives are what make the difference. Chevron and Shell are very proud of their additives and it reflects in their pricing. Costco's additive has the same benefits at better pricing. I run my aquarium maintenance business and am supervisor at Costco gas station.
 

lbv150

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Before we get into the low versus high octane....besure you know just how fuel with different levels of octane burns. For starters it does not burn hotter or destroy turbos.

Not sure how the other models are tuned but on the '16 Expy the engine control system in conjunction with compression ratios is calibrated for maximum horsepower and torque with 91+ octane. You can run lower and the ECM will compensate for it and the engine will deliver less HP and torque.
 

rjdelp7

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Before we get into the low versus high octane....besure you know just how fuel with different levels of octane burns. For starters it does not burn hotter or destroy turbos.

Not sure how the other models are tuned but on the '16 Expy the engine control system in conjunction with compression ratios is calibrated for maximum horsepower and torque with 91+ octane. You can run lower and the ECM will compensate for it and the engine will deliver less HP and torque.
High Octane has more additives and hydrocarbons and burns hotter. Engines that require premium, will de-tune(if knock is detected), when 87 octane is used. A stock 87 octane engine, does not have reserve power if 93 is used. The engine can not sense what fuel is being burned, only knock and pings. I have owned two vehicles that required premium. A Lincoln Intek 32v ohc and Mustang 5.0 coyote. There is no way Ford would require a engine, used in the F150 to require premium(for extra power). The extra expense, would turn people off. The whole concept of the Eco-boost, is to save money on gas.
 
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LokiWolf

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High Octane has more additives and hydrocarbons and burns hotter. Engines that require premium, will de-tune(if knock is detected), when 87 octane is used. A stock 87 octane engine, does not have reserve power if 93 is used. The engine can not sense what fuel is being burned, only knock and pings. I have owned two vehicles that required premium. A Lincoln Intek 32v ohc and Mustang 5.0 coyote. There is no way Ford would require a engine, used in the F150 to require premium(for extra power). The extra expense, would turn people off. The whole concept of the Eco-boost, is to save money on gas.

:rolleyes: This is right out of the manual:

"For vehicles with EcoBoost engines, to
provide improved performance, we
recommend premium fuel for severe duty
usage such as trailer tow."

The paragraph before:

"We recommend regular unleaded gasoline
with a pump (R+M)/2 octane rating of 87.
Some fuel stations offer fuels posted as
regular unleaded gasoline with an octane
rating below 87, particularly in high altitude
areas. We do not recommend fuels with
an octane rating below 87."

You can theorize how ever much you want to. You are basing your experience of the 3.5TT Eco based on one buddy, and never driving one day to day. We do. I drive a 2.7LEco Edge Sport, and a 2017 Expedition. 93 Octane makes a difference even stock on these motors, period. I measured it on my GTech. Can you run 87, YES. I do daily in the Expy. In the Edge I am running a LMS 93 Aggressive tune...needless to say I put 93 in it. I run 87 in the Expy most of the time, because it is my wife's DD and average driving, it makes very little difference.

Before we get into the low versus high octane....besure you know just how fuel with different levels of octane burns. For starters it does not burn hotter or destroy turbos.

Not sure how the other models are tuned but on the '16 Expy the engine control system in conjunction with compression ratios is calibrated for maximum horsepower and torque with 91+ octane. You can run lower and the ECM will compensate for it and the engine will deliver less HP and torque.

This:waytogo:

Higher Octane is merely more resistant to self igniting in the presence of pressure, temperature, and hot spots.
It used to have a lower energy content, but modern refining has made high density high octane fuels. Just for clarity, my degree is Chemistry...don't get me started on the general misconceptions on fuel!
 

rjdelp7

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:rolleyes: This is right out of the manual:

"For vehicles with EcoBoost engines, to
provide improved performance, we
recommend premium fuel for severe duty
usage such as trailer tow."

The paragraph before:

"We recommend regular unleaded gasoline
with a pump (R+M)/2 octane rating of 87.
Some fuel stations offer fuels posted as
regular unleaded gasoline with an octane
rating below 87, particularly in high altitude
areas. We do not recommend fuels with
an octane rating below 87."

You can theorize how ever much you want to. You are basing your experience of the 3.5TT Eco based on one buddy, and never driving one day to day. We do. I drive a 2.7LEco Edge Sport, and a 2017 Expedition. 93 Octane makes a difference even stock on these motors, period. I measured it on my GTech. Can you run 87, YES. I do daily in the Expy. In the Edge I am running a LMS 93 Aggressive tune...needless to say I put 93 in it. I run 87 in the Expy most of the time, because it is my wife's DD and average driving, it makes very little difference.



This:waytogo:

Higher Octane is merely more resistant to self igniting in the presence of pressure, temperature, and hot spots.
It used to have a lower energy content, but modern refining has made high density high octane fuels. Just for clarity, my degree is Chemistry...don't get me started on the general misconceptions on fuel!
I rest my case. Based on your owners manual, this engine does require premium. It is de-tuned for 87 octane. It is cleverly worded as "severe service use". The Eco-boost is over hyped marketing, that probably will not save people money and future, costly repairs, will lower resale values.
 

lbv150

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The octane rating, is in your owners manual. Using premium, when 87 is required is a waste of money. The "Eco-boost" is not a high performance engine, it is a fuel saver, hence "eco". From what I read about it, it does not save, all that much. Paying for premium, would defeat any savings. The EB engine adds $1400 to the price of the truck. It has more parts, to fail, out of warranty. Ford went all in, with eco-boost(v6 turbo charging), but GM and Ram trucks, still have V8s. Ford should give a V8 option. I personally will never own a full size truck, with a V6.

Not a high performance engine???? Bahahaha!!! Take a new Expy for a ride...it blows away the V8s....very very impressive. Almost as much fun as my Mustang GT.
 

LokiWolf

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I rest my case. Based on your owners manual, this engine does require premium. It is de-tuned for 87 octane.

You are WRONG...you said and I quote:

The octane rating, is in your owners manual. Using premium, when 87 is required is a waste of money.

It is not a waste of Money if somebody wants the best "Performance" and "MPG" out of the Motor. The decision is up to the owner. Drive it normal, and never get hard into the throttle, use 87 and save some Money. Want the best Performance, use 93. Seems pretty simple to me!

You keep saying the Motor has no additional value over the V8, same MPG for more power. The new second gen 3.5TT has EVEN more power over the 5.0, and because of a dual injection system will most likely get better MPG under light load.

Not a high performance engine???? Bahahaha!!! Take a new Expy for a ride...it blows away the V8s....very very impressive. Almost as much fun as my Mustang GT.

Yep...
 

rjdelp7

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The whole idea behind the ECO boost is V8 power, USING LESS FUEL! Not one person, has said a word ABOUT MILEAGE. My point is, what are you saving, putting gas that cost .40-.70 cents more a gallon? The 5.0l in the F150 is cheaper, fuel mileage is similar and 91 octane not required. When the power train warranty runs out, owners have more parts to worry about. Bring back the V8 in the Expedition!
 

lbv150

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The whole idea behind the ECO boost is V8 power, USING LESS FUEL! Not one person, has said a word ABOUT MILEAGE. My point is, what are you saving, putting gas that cost .40-.70 cents more a gallon? The 5.0l in the F150 is cheaper, fuel mileage is similar and 91 octane not required. When the power train warranty runs out, owners have more parts to worry about. Bring back the V8 in the Expedition!


You are not saving $ you are gaing performance and a cleaner engine by running a premium grade fuel. Ok...my '04 and '06 with the 5.4 V8 gets on average 12mpg. My '16 gets 18mpg and over 21mpg on the highway cruising 75mph. Power and performance does not compare to the 5.4 three valve V8 which I consider one of the worst Ford engines ever produced. I'm a V8 person and was not sure of the V6 twin turbo...now I'm sold on it.
 

rjdelp7

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You are not saving $ you are gaing performance and a cleaner engine by running a premium grade fuel. Ok...my '04 and '06 with the 5.4 V8 gets on average 12mpg. My '16 gets 18mpg and over 21mpg on the highway cruising 75mph. Power and performance does not compare to the 5.4 three valve V8 which I consider one of the worst Ford engines ever produced. I'm a V8 person and was not sure of the V6 twin turbo...now I'm sold on it.
Your post says"2006-sold with 230,000mi." How is that possible, if the 5.4l is the worst engine ever? 18mpg, city in a 5000lb vehicle, that sounds a bit high.? I am glad you love, the Eco, but 5.0l would perform the same and cheaper to boot. By comparison, my 2000 4.6l, got 20mph highway. I like to see a diesel option available.
 

07xln

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Rjdelp7 it's time to give up buddy. Every time you post it's just more wrong on top of wrong


I started out running 87 in my 17 expy then got bored one night and browsed the owners manual and read that 91 was recommended (not required Rjdelp7) when towing or in hot climates and would provide better performance. Since then I've only ran 93. To me it feels like the truck runs better. I don't pay attention to gas mileage really and it's my money so I'll buy 93 if I want.
 

ExpeditionAndy

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How do justify spending, a extra $1400 for this engine? What about break downs? Have you had issues? A co-worker has had his in the shop twice already. Both times were turbo related problems. One was a oil leak and one turbo actually failed(Ford claimed only second one, in country). His truck was in the shop for two weeks. They considered replacing the whole engine, but were able to fix it. Now he is close to being out of warranty and does not trust it anymore. The 93 octane issue, I am skeptical of any power gains. The extra heat from burning higher octane, is harder on the turbos.
The 3.5L Twin Turbo EcoBoost engine is standard in Expedition, there is no extra charge, there are no other options. The EcoBoost engines had some early problems. This engine has been in service since 2011. There were issues with the cam phasers (this engine has 4, for intake and exhaust on each bank) and timing chains on the early engines. It has the usual carbon issues that all direct injection engines have. One way to lower the carbon build up is to use full synthetic oil because of its higher temp capabilities.

I love the EcoBoost in my 17. It has way more power than the 5.4L Triton, and accelerating from 40 to 70 on an entrance ramp takes about 2 seconds compared to the 4-6 seconds that the 5.4L Triton used to take in my 05. I have the extended warranty so I'm not worried about the EcoBoost.
 

JExpedition07

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I've never driven an ecoboost but they seem impressive. I have however driven 6.7 power strokes and 6.2 gas in super duties and they haul a**. I understand the ecoboost is great but a V8 option wouldn't be bad. An ecoboost probably couldn't touch the 6.2 V8 in the super duties, those things feel like they want to rip the truck into pieces when you hammer them. And GM offers a 6.2 V8 in escalade and yukons I wish Ford put one one in on high trim level expeditions.
 

rjdelp7

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Rjdelp7 it's time to give up buddy. Every time you post it's just more wrong on top of wrong


I started out running 87 in my 17 expy then got bored one night and browsed the owners manual and read that 91 was recommended (not required Rjdelp7) when towing or in hot climates and would provide better performance. Since then I've only ran 93. To me it feels like the truck runs better. I don't pay attention to gas mileage really and it's my money so I'll buy 93 if I want.
Recommended or required, what's the difference? Having to use premium, in a SUV is unacceptable and a waste. Ford is trying to appeal, to soccer moms, who want gas mileage, with the 3.5l. If I worried about gas mileage, I would not drive a Expedition. I do not know why, they can't give people a V8 option. I bet it would outsell the 3.5lt
 

JExpedition07

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Video of 6.2 vs ecoboost in 150s, sorry to get off topic but it is a relevant issue about options, I think it's fair to ask for a V8.
 

ExpeditionAndy

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Recommended or required, what's the difference? Having to use premium, in a SUV is unacceptable and a waste. Ford is trying to appeal, to soccer moms, who want gas mileage, with the 3.5l. If I worried about gas mileage, I would not drive a Expedition. I do not know why, they can't give people a V8 option. I bet it would outsell the 3.5lt
I drove Mercedes ML350s, 2003, 2006, 2009 all of the required premium fuel IT is very acceptable. If you can't afford it then you can't play with this crowd sorry. You don't have any like minded individuals here.
 

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video doesn't really mean much 6.2 in a 5700lb truck. gobs of power
3.5 has tons of power
still a tq vs tq race, 6.2 has more tq. off line.
and the 3.5 was just barley one truck length behind, but never faded, in fact it stayed right there.
3.5 you can still tow 9500 lbs in the expy, and when not towing you get pretty dam good mpg
where as the 6.2 drinks fuel like a 747 , empty or loaded. not as bad as the v10..but very close
back few years i ran diesels and pushed them to the limits on dyno days and scarring the kids in their little rice burner fast and furious cars.
nothing says you just got your ass spanked like a 8000 lb crew cab dually leaving you in a fog of black smoke. nothing replaces raw tq and omg hp to keep you going.
 

JExpedition07

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My fathers 2016 F250 has the 6.2 and it gets about 14 to 15 average in summer which my triton gets 15.5 so that's not bad in my book as it's a heavier vehicle too.
 

JExpedition07

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My other question is if the 3.5 is going to be such a workhorse why isn't available in the heavy duty trucks then. I feel if it could really compete with V8 on long term reliability it would be up with the big dogs. Maybe they just don't see a segment that would buy a V6 in that size vehicle and that's it im not sure.
 
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I have to agree with some of what rjdelp7 said. If ANY manufacturer designs a truck motor that requires premium they would be shooting themselves in the foot. Companies with fleets wouldn't buy it, and most average consumers would stay away from it also unless they had money to burn. While I like my eco I would've opted for the 5.0 if it was an option. Not because of sound or power or gas mileage. Because in the end I think it will be a less expensive motor in the long run
 
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