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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
Messages
12
Likes
2
Location
San D
I haven't dyno'd on 87, but I took a ton of datalogs while using it to get my OAR adjustments while tuning. The FiST didn't hate it nearly as much as my FoST did. For someone that doesn't use WOT often it's actually not a horrible choice.
Hey dyn, did u notice any negative timing corrections on 87, especially at low rpm part throttle?
 


dyn085

2000 Post Club
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820
Location
Vancouver
Hey dyn, did u notice any negative timing corrections on 87, especially at low rpm part throttle?
Not at all, actually. The only way I was able to get negative corrections was to be WOT with 87 octane on a 93 base tune and even then the corrections weren't that bad. Quite honestly, it was surprising.
 


JasonHaven

Active member
Messages
525
Likes
120
Location
Washington
Wish we could change answers on polls... I'm strictly 93 now that I'm tuned. I used to run whatever when in stock configuration.
 


Messages
223
Likes
28
Location
Miami
Surprising results on 87 vs 93. I did wot pulls in third gear from 40-80 mph. Stock tune 87 octane stock airbox time to complete 6.5 seconds. 1/4 tank I the car. Test 2 93 octane MAP intake and stock tune. Result 6.5 seconds full tank. This was measured using a race logic, really slick unit. I did a 40-80 because it doesn't require a shift and takes driver out of the equation. My .02
 


Waterfan

Active member
Messages
565
Likes
171
Location
SoCal
Didn't read the thread, apologies if duplicate. A poll than included >93 octane and or ethanol options would be fun too. Might also want to differentiate between daily driving and "other settings". (maybe that's 2 polls or an option on "multiple fuel types used"?)
 


LILIKE16ST

Senior Member
Messages
862
Likes
252
Location
Saltville
I've put 10,428 in 3.5 months just driving everywhere. Lol. I bought it so I could enjoy it. And I put 91. I do commute to work tho. 60 miles round trip either 4-5 days a week. And I drive EVERYWHERE on my time off lol
I realize this post is old but finally I find someone who's got me beat on racking up miles I've done just over 6500 in just over 3 months and I thought that was a lot lol. I've only ran 93 always in mine even had the dealer fill it with 93. I been running the Livernois motorsports 93 tune (awesome tune!!) Since 2800 so now its a must...
 


Messages
343
Likes
101
Location
Sheboygan
So here's my dilemma. Of the reasonably convenient options around me, my choices are 91-ethanol free, or 93-with 10% ethanol. Can't figure out which is the better option.
 


LILIKE16ST

Senior Member
Messages
862
Likes
252
Location
Saltville
Surprising results on 87 vs 93. I did wot pulls in third gear from 40-80 mph. Stock tune 87 octane stock airbox time to complete 6.5 seconds. 1/4 tank I the car. Test 2 93 octane MAP intake and stock tune. Result 6.5 seconds full tank. This was measured using a race logic, really slick unit. I did a 40-80 because it doesn't require a shift and takes driver out of the equation. My .02
I'm thinking something is up with these results. Spool tuning (cj pony parts) went from 204 whp to 218 whp and added like 20-30 torque to the wheels with a simple fuel switch on a stock focus st going from 87 to 93 and I'd imagine results would be similar on s FiST. I never ran 87 in mine even had the dealer fill it with 93 but it pulls the crap out of timing and stuff to keep knock in check and it has to have a decent impact on power. For one you had 3/4 tank more fuel on the 93 run which assuming 8 gallons would be like 50 lbs or so which would make a decent impact on such a short burst. Also having aftermarket intakes on stock tune have been known to not add power....the computer senses the extra air and compensates for it adjusting things and can sometimes overcompensate resulting in lost power....it's pretty well known. I'm not familiar with that intake but is the filter exposed to under hood heat? Could be heat soak...also the conditions could have been different and the intercooler could have been more heat soaked on your 93 run. Its pretty well known 93 has a significant jump in power over 87 in these cars so there has to be other factors at play here. I don't doubt your results just saying there is another reason for them other than "93 does nothing for power over 87 in the FiST". just my .02
 


Messages
312
Likes
40
Location
Peoria
Does the FiST adjust on the fly or does the ECU need to be reset, fuse pulled, etc. to have it re-learn octane level? I used to have to pull a fuse or the negative battery cable if I wanted best results when changing octane in cars that are over 10 years old now. LOL

Thanks.
 


OffTheWall503

1000 Post Club
Messages
1,991
Likes
456
Location
Memphis, TN
So here's my dilemma. Of the reasonably convenient options around me, my choices are 91-ethanol free, or 93-with 10% ethanol. Can't figure out which is the better option.
This car is designed to take E10 fuels, higher octane is more important than ethanol content (unless you have access to E85 and can make an E30 mix).
 


Messages
331
Likes
144
Location
Gloucester, VA
Does the FiST adjust on the fly or does the ECU need to be reset, fuse pulled, etc. to have it re-learn octane level? I used to have to pull a fuse or the negative battery cable if I wanted best results when changing octane in cars that are over 10 years old now. LOL

Thanks.
It learns on the fly. Do you have a Cobb AccessPort?
 


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