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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

Sourskittle

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#81
Really? Learn something new every day. I thought they added the ethanol to bump the octane. Thanks for clearing that up.
You right, its less than 93oct, the eth adds to the oct and gets it to 93oct. Thought you were saying 93 with eth isn't 93oct.

For power, I'd take 93oct with eth over pure 93oct anyday. Not for mileage, not for storage life, but for all out power.

I may even sneak a gal of e85 into my car sat before going to the track :)
 


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#83
I live less than 20 miles from where Exxon refines the stuff so I should be able to get whatever they make. Not the case though.
 


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#86
Just flipping through the ST owner's addendum and found this. I've run both and I can't tell much difference. Keep in mind, I'm not gassing on it like I would have 20 years ago (I'm 42!!). I drive it like I'm paying for it and try to get good MPG as my daily commute doesn't offer any reason to drive differently. I'm about to put my 5th tank in and will switch back to premium (93) to see if there's any difference. I've done two tanks of 87 and two tanks of 93. When I do get a tuner, obviously 87 will be irrelevant.
 


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#87
I filled up the other day with 93. Like I said before I almost exclusively run 87 except for the 89 here and there. I could tell NO DIFFERENCE. I understand that in order to run those aggressive tunes you have to run 91/93 and I get that. But without having a Cobb tuner the difference wasn't noticeable. Acceleration, engine idle, gas mileage, etc were all nearly identical.
 


dyn085

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#88
I couldn't imagine running regular fuel in the FiST. If I wanted a car to run regular I would have either bought used or bought a non-performance trim level. I don't understand spending thousands of dollars for performance and then trying to save $150 a year by removing some of it. It costs less than $5 a tank, is that really what's making or breaking finances these days?
 


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#89
Filled up with 92 once while on the drive to TN, took the tune off while I ran through the tank. Even the 93 from various stations around here is awful. Keeping the tune off until I get home to the stations I know. Either way, still running 93 no matter what.
 


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#90
I couldn't imagine running regular fuel in the FiST. If I wanted a car to run regular I would have either bought used or bought a non-performance trim level. I don't understand spending thousands of dollars for performance and then trying to save $150 a year by removing some of it. It costs less than $5 a tank, is that really what's making or breaking finances these days?
When you go through a tank of gas a day for work talk to me. That isn't $150 a year difference. Hell the manual says to use 87 or better. On a stock car what are you losing between 87 and 91/93? 2 HP and 3 ft/lbs?
 


dyn085

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#91
When you go through a tank of gas a day for work talk to me. That isn't $150 a year difference. Hell the manual says to use 87 or better. On a stock car what are you losing between 87 and 91/93? 2 HP and 3 ft/lbs?
If I was driving a full tank of fuel a day for work, the FiST is definitely not one of the cars I would have bought-at least not if I was so concerned about mileage and the price difference of regular/premium. But that's just me.

I haven't seen dyno work on the FiST and have not have I run 87 on the butt dyno, but I can say that I have seen and felt the difference in my FoST. There was even a noticeable change in my n/a Mk3 Focus. Just because you personally can't feel/notice it doesn't mean it isn't there. I can't imagine Ford optimizing their n/a vehicles for premium but not the FiST.

And the reason the manual states 87 is because some mid-western states offer 85. There you would have to use mid-grade at the minimum. But if you're bringing the manual in as your evidence, then note that the very next sentence states that premium *will* provide increased performance. Not 'might' or 'may' or 'could', but 'will'.

It's your car so do what you want, I'm just saying that I've seen enough evidence/data from other vehicles in the Ford lineup to believe in the fact that they tune for 91 at a minimum and then build in enough adjustment to let down to 87 be used. I'm pretty sure that there is a blurb in there staying that the maximum power-output was obtained with the use of premium.
 


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#93
I'm working on finding an old Civic/Corolla/Camry, etc... to use as a work vehicle. Then I can park the FiST and do whatever the hell I want to do to it. Then I can think about running only 93 and getting a Cobb tuner.

I do live roughly 10-15 miles from the Royal Purple Raceway and they sell race gas out of a couple pumps out there. Ideally that would be the way to go.
 


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#94
With the tuners being set up for 93 octane, I don't know if race gas would net you anything.
 


dyn085

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#95
With the tuners being set up for 93 octane, I don't know if race gas would net you anything.
^ This. Higher octane is only of benefit if the ECU can accommodate it, and I would imagine that OEM tuning is 91 or 93 max. But you could always get a pro-tune geared around what is available.

Don't get me wrong-I'm not saying that people should have to run premium, I just don't understand the concept of sacrificing performance for a few bucks every few hundred miles. People can justify a $500 tuner but can't justify an extra ~$4 a tank. I don't racecar everywhere I go, but I like knowing that my car will go as designed when I hit the go-pedal. Maybe it isn't noticeable or as noticeable in the FiST, but my FoST absolutely falls on its face when timing is pulled on 87. The only benefit you get by timing being pulled is engine longevity, and I would rather have it pull on a bad tank of 93 than 87...

I don't even understand why dealerships would out 87 in the ST's with the possibility of test-drives. You know people are going to dog on it and I can't imagine it shows well when the torque disappears far before redline.
 


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#96
Because Ford says no where except in the horsepower rating that 93 octane is needed or required. It doesn't say it anywhere on the car. My salesman made a point to tell me Ford recommended 87 octane. It was hard for me to argue with him when I couldn't find the word premium anywhere on the car. I'm not arguing either, just saying what I know I was told and what I read in the manual. Like I said, if I feel a difference or see a difference, I'll stick with 93.
I was referring to an aftermarket tuner set up for 93.
 


dyn085

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#97
Because Ford says no where except in the horsepower rating that 93 octane is needed or required. It doesn't say it anywhere on the car. My salesman made a point to tell me Ford recommended 87 octane. It was hard for me to argue with him when I couldn't find the word premium anywhere on the car. I'm not arguing either, just saying what I know I was told and what I read in the manual. Like I said, if I feel a difference or see a difference, I'll stick with 93.
I was referring to an aftermarket tuner set up for 93.
You're absolutely right, it's not *required*. If it was, how many Americans do you think would turn away from it?

I'm not arguing either, I really have no bearing on what anyone else uses in or does to their vehicles. I just enjoy discussing things. You can also get a tuner set up to optimize 87. I had one on my Focus (one of five tunes) even though I never used it.
 


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#98
I believe Livernois said they really didn't see any gain when trying to tune for 87 octane, if I remember correctly. I would absolutely run 93 octane if I spent $500 for an aftermarket tuner for the sole purpose of making it faster, which I plan to do after folks have had them on these cars for a few months.
 


dyn085

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I just stopped by www.fastlaneturbo.com and they sell the SCT X4 tuner. I haven't researched it yet but it's an alternative to Cobb.
While it is indeed an alternative, I think the better value lies in the Cobb-unless you simply want to load a tune and unplug. In that sense you could save ~$70 if so. The only other reason to choose it would be if you're dead-set on using a pro-tuner that doesn't tune with Cobb.

Probably better suited in a tuning thread.
 


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