Ecob01

I've been testing the differents between Shell 87 and 93 octane only a vary slight inprovement in mileage. I still get 21.6 mpg on 87 octane.

69428SCJ

Your original retort made no mention of how the ethanol situation was escalated, and lead everyone to believe the whole fiasco belonged to Bush. My post explained how the bills got there and how they were voted in. I'm far from an extremist and believe BOTH sides of the story should be told....and yes ethanol sucks.

acadianbob

Different engines but our Audi S4 with a normally aspirated V8 sees a 5% increase in fuel mileage going from 87 to 91. It is also noticeably quicker.

Our Jetta Turbo 1.8 is VASTLY quicker on 91 vs 87 and sees a 10% increase in fuel mileage. I drive this car long distances over the same roads and proved this many times.

I also have the Ecoboost. Have not tried 91 octane yet as I'm still on my 2nd tank of fuel. (36 gallon tank last almost a month!) But it would not surprise me at all to see some positive effect from 91 octane.

I liked the idea of taking the same truck and putting it on a dyno with the 2 different octanes to see for sure.

So, an effect from 91 octane can be real in my experience. To make a blanket statement of no benefit is untrue. Whether it helps the Ecoboost seems to be indeterminate.

engineermike

So, why didn't Ford give the EB dual power ratings based on octane like they did the Mustang 5.0?

69428SCJ

Most manufacturer's don't...yet their owner's manuals clearly state for best performance use premium...Heck even Ford doesn't for the 6.2 in the Raptor.... although sales literature clearly states that HP/TQ ratings are based on premium fuel....meaning it's not the same if you use the "recommended" 87. Most of us have no problem reading between the lines.

Pongdadong

I noticed no difference in running 87 to 93....none...however I did notice I have less money in my pocket

69428SCJ

Wait until it's hot outside.

mirandan50

There seems to be a huge diversity in performance amongst drivers of roughly the same engine. For info purposes I drive an FX4 SCREW. Everything is pretty much stock. I have been tracking my fuel usage very closely for the last 2600 miles. I might even say to the extreme as I also include things like, date, price, octane types, vendor (always shell so far), and driving type – which logs how I drove on average (off-road, highway, city etc.)

I have logged using only 87 and 93 Octane so far. Reason – I wanted to see if a difference would be found from one extreme to another.

Using 87 Octane my average on 2 tanks of gas came to 17.9 mpg
Using 93 Octane my average on 2 tanks of gas came to 17.4 mpg

I realize this is not conclusive and there are literally hundreds of variables that could have changed the outcome of the results found up to this point.
I did not notice any improvement of power to the truck of any kind based on octane levels.

Pongdadong

When it was warmer outside I was getting 17 mpg with 87 octane since it has gotten colder I am around 14.5-15 mpg city. Unless there is a tune that comes out for 93 octane I won't be purchasing that again.

69428SCJ

I'm not noticing any difference this time of year either. When it was 100+ degrees I noticed that the truck was performing a little different. I started putting 93 octane in it and it performed better and was giving me about .8 to 1 mpg better. I drive 5K miles a month...same route. I went back to 87 a few times and lost the mileage and pep. It really was noticeable. When it cooled off I started running the lower octane again and have noticed no difference. I will wait until April/May and see what happens with mileage and performance again before trying/running the 93 again.