engineermike

FYI, octane does not affect burn rate. Burn rate and resistance to detonation are two different things. The burn rate of 87 and 93, as well as the btu, content are the same. I actually have some data that shows 116 octane race fuel burns faster than 87. Your other points are correct, though. You can gain power IF you aren't already running optimum timing advance. This is obviously the case on the Mustang 5.0, which has 2 different hp ratings (87 and 93). However, since Ford didn't give the EB 2 different ratings, I am lead to believe there is no WOT hp advantage to 93 in the EB. This may be different for long-duration high-load towing.

Sorry for the off-topic post.

5111

My city fuel efficiency has been 13.2 since the last fill-up last week!

TommyB80

Mine went down from 18mpg all around to 16.5-17mpg.

GJR

Yup, Here in New England my EB has reduced from 18.5 mpg around town to 17.5 mpg since the cold weather has moved in and the gas blends have changed over to winter mix. Summer months have been around 21 Hwy. Headed up to Canada this week on a hunt so we'll see what affected the temps have on Hwy mpg.

First_Timer_FX4_EB

AND SkiSmuggs
Thanks a lot for the info... I am very new to truck or Motor... eventhough I drove car for 20 years... never though about geting information like this one.. Really Thanks!

SkiSmuggs

Thanks for the clarification and not off-topic as the question was whether higher octane would offset the winter blend.

clexell

My city/hwy average dropped from 18.5 to 17.0 since the colder weather and winter blend fuel. Still great MPG from a full-sized truck!

BlueFlameMetallicFX4

Mine recently went down to 15.5 with 30 degree temps...to be expected though. As far as warming up, this is the fastest warming engine I've ever experienced...within 5 minutes and the heat is there.

Loki 5.0

Can you explain this a little further. I thought cold air was denser so the mileage was suffering because the amount of fuel was being fattened up to correct the A/F ratio. More air in the cylinder, more fuel, more power, less mileage. I always have to re-tune my 2 cycle equipment twice a year when the temps change , when it's cold they scream.

dcfluid

The power available from the engine can be greater due to a colder air intake temperature however, it's -26° C here right now and from experience with turbo diesels for 25 years the effects of the entire truck being frozen far outweighs any power increases or losses from air temps or fuel quality. Increases from frozen tires, oil, grease, coolant, snow resistance, etc demolishes any comparisons that can be made between winter and summer. Then there's idling time.
The only time I could tell you for sure about a difference is running winter diesel in summer and summer diesel on winter. We even have arctic blend here. There is a one to two mpg difference between the grades.
I see much less difference in gasoline grades. For all the same reasons my ecoboost above is losing it's average mpg's about 2.5l/100 km right now due to cold, deep snow, ice, 4x4 use, and playing around .
My average would be worse if the remote start recorded the fuel used, but I have been pleased with how little it uses compared to my last V8 while warming up. Though it does take a little longer to do so.