Fuel

[agentl074]

I was reading that the Ecoboost has two fuel maps -- one for 87 and one for 91... is this true, or does it adapt to whatever you throw in it?

[lildisco]

Doesn't have 2 different fuel maps. They just have adaptive tuning based on what octane you throw in it. It can advance or pull timing based on load, octane, knock etc.

[WWWPerfA_ZN0W]

Ecoboosts run off knock sensing. The tech is meant to run ultralean, and knock data helps determine maximum timing safely available under any given condition. There is no octane sensor as such, it is extrapolated from the knock data and the spark tables the PCM can reference. This is how you discover 93 is not always 93 LOL.

[akirby]

It will advance the timing to take advantage of higher octane - at least up to 93.

[NeuroBeaker]

I've been trying to find out whether the naturally aspirated 3.5 V6 does any timing modification depending upon the type of fuel used.

 

The manual says that the minimum is 87 octane, and it mentions that EcoBoost engines (which I don't have) should use higher octane fuels when doing heavier work (e.g. towing), however there's not mention whether there's any benefit to using a premium fuel in the naturally aspirated engine.

 

If nobody knows the answer, I'll call the Ford customer service line on Monday and then report back.

 

All the best,

Andrew.

[t0lkman]

how about mpg? has anybody calculated mpg/price? maybe worth to fill 93?

[ben senise]

…there's not mention whether there's any benefit to using a premium fuel in the naturally aspirated engine.

 

i have a 2016 titanium AWD with the 3.5 V6. i get about 10% better mileage with 89 octane over 87 and even a bit better in the summer. It feels like it's got more pep but that could be influenced by knowing what's in the tank. mileage is empirical but power is subjective since i haven't had the car on a dyno. i've tried 91 octane and don't get better mileage nor do i feel more pep.

 

of course, your mileage may vary (pun intended!)

[akirby]

Summer blend fuels typically get better mpg due to the additives, at least in the southern US.

[NeuroBeaker]

Thanks for sharing your experiences, Ben. I guess I can calculate whether there's a 10% difference in price between 87 and 89 octane to determine whether the uprated fuel is worth purchasing.

 

Akirby, what do you mean by "summer blend"? I've only recently returned to the United States from the United Kingdom and was unaware that there was any seasonal difference in fuels.

 

All the best,

Andrew.

[akirby]

In most of the US summer temps can approach 90 degrees F or higher. Evaporation and gasoline vapors are a problem so they use different additives to reduce the vapors in the summertime. A side benefit of the additives is slightly better mpg.

[NeuroBeaker]

Thanks akirby, much appreciated.

 

All the best,

Andrew.

[ben senise]

Summer blend fuels typically get better mpg due to the additives, at least in the southern US.

same up here in canada which is why i get better economy in the summer. it might also have something to do with the engine temp at start-up but when i drive, it's usually plenty of time to get to normal operating temperatures.

 

Thanks for sharing your experiences, Ben. I guess I can calculate whether there's a 10% difference in price between 87 and 89 octane to determine whether the uprated fuel is worth purchasing.

 

Akirby, what do you mean by "summer blend"? I've only recently returned to the United States from the United Kingdom and was unaware that there was any seasonal difference in fuels.

 

All the best,

Andrew.

 

for me the price comes out about the same, give or take a cent or two.

 

i would think that most countries that have seasonal temperature differences use different blends. some place like the middle east or south-east asia that are just hot all the time might not. knowing UK weather, i would be pretty sure that they do as well.