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What octane is everyone using?

What octane is everyone using?

  • 87 Octane

    Votes: 31 6.0%
  • 89 Octane

    Votes: 7 1.4%
  • 91 Octane

    Votes: 176 34.3%
  • +93 Octane

    Votes: 299 58.3%

  • Total voters
    513

M-Sport fan

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This is a 100% incorrect statement when it comes to the MED ECU in the Fiesta ST.

Even the OEM programming makes use of dynamic ignition timing and fueling. The car will show power improvements with higher octane and more knock resistant fuel. It's very easy to see how it works if you look at the ECU tables and programming. It's also been proven:

http://www.fiestastforum.com/forum/threads/10046-Second-FiST-2016-Fiesta-ST
^^^EXACTLY the post I was going to cite in response to Intuit's post! [thumb]

We are ALL learning here! [:)]
 


Messages
209
Likes
123
Location
Easton
Looking at the map below you can see why those of us in the west are asking questions about 93 Octane Fuel.
It looks readily available back east, but rarely in the west

You can go to the map directly and zoom in/out
https://www.zeemaps.com/map?group=1385950

View attachment 12945
WOW, I am blessed to be in a hot spot of 93!! I had no idea the lack of 93 out west. I wonder why?

Sent from my VS985 4G using Tapatalk
 


M-Sport fan

9000 Post Club
Messages
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Location
Princeton, N.J.
Looking at the map below you can see why those of us in the west are asking questions about 93 Octane Fuel.
It looks readily available back east, but rarely in the west

You can go to the map directly and zoom in/out
https://www.zeemaps.com/map?group=1385950

View attachment 12945
You could probably move that whole east coast cluster of 93 availability straight into the whole middle band of the country from border to border, IF that map were for E85 availability instead. [wink] [:(]
 


Messages
24
Likes
3
Location
Lake Zurich
Seeing that the manual calls for 87 octane as a minimum, we use 87. Car does not get beat on, and does not have anything modded yet. Once it gets a premium tune and mods, then we shall go 93 octane.
 


Messages
312
Likes
40
Location
Peoria
SORRY, that was the link that worked in razorlab's post in this thread. [:(]

Try this one;

http://www.fiestastforum.com/forum/threads/10046-Second-FiST-2016-Fiesta-ST
Thanks! I'm familiar with razorlab from evolutionm.net. Interesting that he's here, too. The pertinent quote I found from his thread: "It really depends on the tune. With Stock and Cobb OTS, around E20 or so is enough to maximize the adaptive timing nature of the tunes while still staying within the parameters of AFR adaption.

On custom tunes, all bets are off and you should consult with the tuner."
 


Messages
61
Likes
16
Location
Thornton
I'm hoping when I pick it up from the Dealer tomorrow, the didn't fill it with regular, which is 85 octane here.
 


Messages
118
Likes
13
Location
Las vegas
I'm hoping when I pick it up from the Dealer tomorrow, the didn't fill it with regular, which is 85 octane here.
Yeah the manual specifically warns against using 85 octane fuel
Its complete BS that they even sell that stuff, it's only usable in old cars with a carburetor

Here's what the EPA says about it.

The sale of 85 octane fuel was originally allowed in high-elevation regions?where the barometric pressure is lower?because it was cheaper and because most carbureted engines tolerated it fairly well. This is not true for modern gasoline engines. So, unless you have an older vehicle with a carbureted engine, you should use the manufacturer-recommended fuel for your vehicle, even where 85 octane fuel is available. Using a lower octane fuel than required can cause the engine to run poorly and can damage the engine and emissions control system over time. It may also void your warranty.
 


Messages
10
Likes
0
Location
Detroit
using 93 octane.
2014 FIESTA ST Supplement says: "Horsepower 197 hp @ 6350 RPM on 93 octane"
 


M-Sport fan

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I'm hoping when I pick it up from the Dealer tomorrow, the didn't fill it with regular, which is 85 octane here.
My dealer filled it with 87, which in a way I was glad about, i.e.; EXTRA motivation to drive it super easy for break-in purposes that first tankful. ;)
 


Messages
61
Likes
16
Location
Thornton
I kind of lucked out. They didn't fill it yet when I took delivery, I got to put premium in it on their new car account.
 


Messages
75
Likes
19
Location
Detroit
It has never seen less than 93 in my hands.

When my new turbo gets here it will be 93 and E30.
I think I might have to get another tune for 91 if I'm
somewhere else regionally though.
 


Messages
75
Likes
19
Location
Detroit
My dealer filled it with 87, which in a way I was glad about, i.e.; EXTRA motivation to drive it super easy for break-in purposes that first tankful. ;)
I have no clue what was in mine. It was the only one within 180 miles and they did a dealer trade for it.
Little did I know my dealer actually drove it back.
 


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