RiverRat5.0

Last tank i got 17.5 Mpg. I usually keep the rpm below 2k but will go 2.5k from time to time. There is always the two times i get near the floor per tank also...This was 50/50 driving and i try to keep it below 65 most times though i will go 80 from time to time. I have 1800 miles on the clock. Hoping to break 18 with this type of driving once the truck has a few thousand more miles. This thing is as economical as my Pontiac G8! But for the OP i dont think the MPG gap is that wide between these trucks being that they both get exceptional mileage. I read that if you run E85 your truck will put out higher numbers. Like 375hp and 390 tq??? Can anyone verify this? A tune would make the 5.0 pretty darn good in comparison to the ecoboost though.

bigal1234

Drive like there is a raw egg between your foot and the gas pedal. You will be amazed at how your gas mileage improves. Of course driving like that isn't a lot of fun but will save you a lot of cash. Then once in a while you can really let it out for fun.
By the way, I just drove about 700km around town and got about 20mpg(imperial).
The best I could get highway in my 2001 e150(5.4) was 19mpg(imperial and highway), so I am really happy with this ecoboost so far.
My F150 is a supercab with 8 foot box and a 373 rear end.
Al

OmahaEcoBoost

I don't know what E85 will do for your numbers but you will certainly see your gas mileage drop about 3-4 mpg.

bb37

According to the EPA fuel economy ratings, the difference between a 5.0 on gasoline and a 5.0 on E85 is 4 MPG using the combined city-highway ratings.

Of course, your mileage may vary.

2011blueoval

It looks to me like the mileage is definitely close enough to the eco already to eliminate worry from my buying decision. 18-19 in a truck is outstanding. My 07 FX4 consistently got 14.

As far as some of the mods that have been mentioned. What kind of power increases are we talking? Does anyone have any thing done to there truck and can maybe give us an idea what an exhaust, intake, tuner or anything like that is doing for them?

Another thing, I was always under the impression that E85 robbed power not gave it more. I don't know where I heard this, but for some reason that is what I always believed. I figured that the less in the same weight truck also was part of the reason for the lower mpg's.

bb37

Ethanol contains less energy than gasoline, so you have to burn more E85 to get the same power as E10 (most "regular gasoline" in the midwest is 87 octane gasoline with 10% ethanol). That's why most cars get worse fuel economy with E85 than they do with E10.

On the other hand, ethanol cools the charge going into the cylinder better than gasoline, so the effective octane rating is higher. This lets a modern spark control system with knock sensor advance the timing more than it could with 87 octane gasoline. Theoretically, the result is more power.

blackknight87

E85 hinders performance and robs mpgs. The only benefits it gives is if used consistsntly you have a cleaner fuel system and it exhausts cleaner .....

Planets already fvcked right? Screw e85.

2011blueoval

This is how I always thought it worked. Though I don't think I have seen many gas stations in the south west that really offer E85 fuel. Though I have never really payed much attention to it.

meogE

Actually E85 increases power. I used to run straight alcohol in the banshee I drag raced. It was a noticeable difference on the butt dyno. However it does decrease MPG because it requires a richer A/F ratio. However I would agree that E85 is pretty useless for saving the planet. Producing the E85 then burning it produces about the same pollution as using gasoline so all it really does is raise corn prices.

soonerjoe

I ran E85 and it felt like it had quite a bit more power. I would run it more if I had a more convenient station.