What octane is everyone using?

[FORZDA 2]

Nope, under 500 miles still. Is there a benefit to 93 over 91 with no tune?

Yes the 93 allows you to get the max performance the engine is capable of. Lesser octanes result in the ecu retarding the timing to keep the knock within limits.

 

[Wouter1407]

I get Super 98 octane in Belgium, it's seems we get better fuel than Muricans

 

[Kazz]

Yes the 93 allows you to get the max performance the engine is capable of. Lesser octanes result in the ecu retarding the timing to keep the knock within limits.

Even beyond 91? That's rather remarkable.

 

[enamelizer]

I get Super 98 octane in Belgium, it's seems we get better fuel than Muricans

98 RON? This is about 93 octane converted to the method used in north america (RON+MON)/2

 

[Wouter1407]

98 RON? This is about 93 octane converted to the method used in north america (RON+MON)/2

So 98 RON = 93 octane? Cool to know.

 

[upier]

93 Octane all the time. Available everywhere I drive.

 

[vegas_]

Since our cars have premium as a recommendation I was curious what octane everyone is using.

I beg to differ but the ST supplement recommends 87 octane fuel

Clearly Ford is recommending 87 octane fuel,
and only recommending 91 for improved performance.
No mention of 93 octane.

Although I only have 2500 miles on the ST
I have been experimenting with both 87 and 91 octane.
I keep track to blended Octane rating of the fuel in my tank.
And it seems I get better MPG with lower octane, the opposite of what one might expect.

BTW I have never seen 93 Octane fuel for sale at a regular gas station.
However Rebel in Las Vegas, has some stations that sell 100 octane Racing fuel,
though a lot of people complain on-line that those station are frequently out
Rebels website says they have 112 Octane Fuel at their Warehouse location

 

[LILIKE16ST]

I beg to differ but the ST supplement recommends 87 octane fuel
View attachment 12856
Clearly Ford is recommending 87 octane fuel,
and only recommending 91 for improved performance.
No mention of 93 octane.

Although I only have 2500 miles on the ST
I have been experimenting with both 87 and 91 octane.
I keep track to blended Octane rating of the fuel in my tank.
And it seems I get better MPG with lower octane, the opposite of what one might expect.

BTW I have never seen 93 Octane fuel for sale at a regular gas station.
However Rebel in Las Vegas, has some stations that sell 100 octane Racing fuel,
though a lot of people complain on-line that those station are frequently out
Rebels website says they have 112 Octane Fuel at their Warehouse location

I don't think the manual is "recommending" you use 87 it's telling you not to use below 87....that's how I understood it anyways. When you use low octane fuels the ECU waits till it actually senses knock before it retards the timing and who's to say how quickly this takes place or if it will take place at all? (Computers can malfunction)....I don't understand why anyone would use 87 fuel on a performance vehicle like the FiST....it makes no sense at all to me. You should get significantly better performance using 91 or higher even on the stock tune not to mention it's just better for the car in general. Just ask the tuners on here about 87 and our cars and see what they think. In particular Livernois Motorsports. They do not recommend using 87 at all even stock. I never did. I specifically asked to have mine filled up with 93 when I purchased it New and I've never used anything but 93 even before I was tuned. I've been using the Livernois motorsports tune since 2800 miles. I used the 93 tune till the crap winter blend gas came along then I switched to the 91 tune which isn't much behind the 93 tune I was using. Still use 93 fuels because we have 87 89 or 92/93 where I live and it's mostly 93 all the big name top tier stations here that I use only carry 93 so I'm using the 91 tune for winter just to be on the safe side but on 93 fuel (albeit crap winter blend 93).

There's just no way I would use 87 in my ST even if I still had the stock tune. Never have never will. To each their own...

 

[M-Sport fan]

[MENTION=6013]vegas_[/MENTION] ; That might be just fine on a granny-like driven, pure factory stock FiST, but I would NEVER EVER risk 87 (or even 89) octane at all, on ANY aftermarket tune (flash OR custom), unless there was a map made specifically for that lower octane, even in winter ambient temps.

BTW; the way I understand it, the whole reason our ECUs have the OAR (Octane Adjust Ratio) programming burned into them is exactly so that the higher octane premium fuels WILL allow more advanced timing, and fuel maps, and allow for more power right up to/at the razor's edge of knock, but I could be incorrect on that.

 

[tiggerbren]

I live in Albuquerque, NM which is about a mile above sea level. 91 is the highest we get but, from what I've heard, 91 is roughly equivalent to 93 octane at this altitude. I'm not sure how that math, works, though. If someone could explain that would be interesting.

My only mods are a high flow filter and 93 octane tune from Stratified. First I ran their 91 octane tune with 91 octane gas. When I switched to the 93 octane tune with 91 octane gas I did notice an increase in power so I've stuck with that for now. I probably won't go to ethanol blends or 100 octane due to the inherent inconvenience, as there are only a few race gas stations in the state.

 

[vegas_]

[MENTION=6013]vegas_[/MENTION] ; That might be just fine on a granny-like driven, pure factory stock FiST, but I would NEVER EVER risk 87 (or even 89) octane at all, on ANY aftermarket tune (flash OR custom), unless there was a map made specifically for that lower octane, even in winter ambient temps.

BTW; the way I understand it, the whole reason our ECUs have the OAR (Octane Adjust Ratio) programming burned into them is exactly so that the higher octane premium fuels WILL allow more advanced timing, and fuel maps, and allow for more power right up to/at the razor's edge of knock, but I could be incorrect on that.

I don't know what they do in tunes, but I suspect fiddling with the OAR algorithm would be appropriate to optimize for 91/93 octane fuel,
In that case, I agree, using anything lower should be verboten.

But I was referring to my stock ST.
I have noticed about 1 MPG lower fuel economy when using premium,
I suspect that's due to my spirited driving when fueled with premium.

No Sunoco stations in Las Vegas, and I don't seem to find 93 anywhere.
But I've been told there are a few stations that sell 100 oct racing fuel, I'll have to give that a try.
Not sure how much change I will see without a tune.

 

[M-Sport fan]

I guess we are fortunate in this area to have MANY good name brand, Top Tier, 93 E10 stations around (Sunoco, Shell, BP, but almost no Chevron).

We are unfortunate, however, to NOT have ANY E85 dispensing stations within a reasonable driving distance, unlike the midwest and southwest areas, where they are on every corner.

 

[vegas_]

100 Octane Fuel

I guess we are fortunate in this area to have MANY good name brand, Top Tier, 93 E10 stations around (Sunoco, Shell, BP, but almost no Chevron).

Well I could not find 93 Octane here (Las Vegas) But I did find 100 Octane Racing fuel
Some of the Rebel gas stations offer it, for $7.99 per gallon
You can find the list here:
http://www.rebeloil.com/las_vegas.html

So I pumped a few gallons in, and doing the blending arithmetic I now have 93.5 Octane fuel in my tank

I doubt if the factory tune could take advantage of anything over 93 octane

 

[SethD]

Here in good ol Belgium we get Euro 95 (95 RON) or Superplus 98 (98) RON. The 1.6 runs on 95, but during running in I get 98. Everybody tells me its not neccesary but I do it anyway.

 

[MoxBoost]

93 from exxonmobil station right by my work.


Sent from my iPhone using Tapatalk

 

[vegas_]

I will say that the car is really fun to drive with that mix I have in it now.
I really can't tell much difference between 87 and 91, so the sweet spot for this car must be 93

Anyone try any of the octane boosters?

 

[Slurp812]

I use 93. The stock car doesn't make the most of it. However the higher end fuels usually have more detergents in them.

 

[Intuit]

I will say that the car is really fun to drive with that mix I have in it now.
I really can't tell much difference between 87 and 91, so the sweet spot for this car must be 93

Anyone try any of the octane boosters?

There's ignition and then there's mechanical timing. Boosting octane may be part of what is required to decrease tolerances for compression ratio, mechanical and ignition timing.

Ignition can be programmatically adjusted to any given point. I believe mechanical valve timing can only be adjusted to a point.

Performance wise, there will be no benefit from running anything outside of normal pump gas. As far as ignition timing, it wasn't programmed for it. Really don't know but got the impression from the manual that it will be maxed out on mechanical timing when running premium 93? Even the stock compression, accounting for the turbo, is basically designed around pump gas.

You're going to have to mod or change parameters before it'll make any sense to run anything "beyond" pump gas.

 

[vegas_]

There's ignition and then there's mechanical timing. Boosting octane may be part of what is required to decrease tolerances for compression ratio, mechanical and ignition timing.
Ignition can be programmatically adjusted to any given point. I believe mechanical valve timing can only be adjusted to a point.
Performance wise, there will be no benefit from running anything outside of normal pump gas. As far as ignition timing, it wasn't programmed for it. Really don't know but got the impression from the manual that it will be maxed out on mechanical timing when running premium 93? Even the stock compression, accounting for the turbo, is basically designed around pump gas.
You're going to have to mod or change parameters before it'll make any sense to run anything "beyond" pump gas.

In much of the country 93 seems to be readily available at the pump.
Ford advertises the HP as 197 with the footnote "tested with 93 octane fuel"
So from that one could assume that the stock ECU takes advantage of 93 octane fuel in some way to get that HP

 

[razorlab]

Performance wise, there will be no benefit from running anything outside of normal pump gas. As far as ignition timing, it wasn't programmed for it. Really don't know but got the impression from the manual that it will be maxed out on mechanical timing when running premium 93? Even the stock compression, accounting for the turbo, is basically designed around pump gas.

You're going to have to mod or change parameters before it'll make any sense to run anything "beyond" pump gas.

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