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Auto octane, and how to choose what's right for you!

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#1
Recently there has been a lot of confusion on tunes and the difference between auto octane and dedicated tunes and what that means.



Auto octane is something the OEM strategy already does. In fact the ford advertised HP numbers are actually tested on 91 octane e10 fuel that is certified for the emissions testing. These ecus have closed loop timing, the ecu can add and subtract timing through the knock logic. The ecu will always try to keep the ignition timing on the borderline of spark knock that is heavily dependent on the fuel. What that means is when you fill up you ST on 87 octane a few things are going to happen. The ecu is going to see more knock retard and less overall timing, as it learns where the spark needs to be it translates this into something call a Knock Octane Modifier. The KOM is effectively the long term fuel trim of the spark world. Based on the KOM, the ecu will modify the base ignition timing and the boost level. In most cases you will not be making advertised HP numbers on 87 octane.



Our ZFG Racing Auto Octane Tune expands this capability allowing the ecu to add more boost and more ignition timing on higher grade fuels. That is where all the power comes from. That along with our killer trans tuning and few other things is what makes our tunes so fast. Our Auto Octane Tunes are setup for 87-93 octane (and any octane boosters beyond 93) as well as up to 30% ethanol.



So why if the ecu is capable of this great auto octane feature would you shut it off and make a dedicated 91 and 93 octane tunes?

The answer is, we don’t shut it off. ALL of our tunes 91/93/e50/e85 (heck even the 707awhp st and 855whp f150) maintain the auto octane features as a safety. We call our tunes dedicated, but the reality is that if you put the wrong fuel in they are going to turn themselves down. This is a key safety feature of our tunes, and from time to time I get customers asking why their car seems so much slower than it was. It only takes 2 seconds to look at the data log and see the KOM has reduces the octane level and overall power.



So if all of our tunes leave auto octane on, what is the difference and why shouldn’t you just get a 93 tune and run whatever fuel you want?

91/93/e50 tunes have some key differences from auto octane tunes. 91 and 93 have higher upper limits for boost and timing. This means that the difference between the lower end of the tune and the upper end of the is larger than the auto octane tune. The issues becomes that if you are on 93 octane and run it to E and fill up with 87 it takes time to adjust. 91 and 93 are, depending on mods, over 100hp higher than what should be run on 87 octane, especially on long pulls. There is risk that computer wont turn it down fast enough to accommodate the fuel change. The risk is small and this works great as a safety, but if you want the most powerful tunes possible on 91/93 the risk is there and it’s not something everyone should be doing on a daily basis. That’s why we have decided tunes.



E50 has more aggressive starting points for timing, higher upper limits for boost, fueling changes, as well as a bunch of other tweaks. The auto octane safety acts much more aggressively on this tune. If you put 87 octane or even 93 in on an e50 tune the ecu will bring the power potentially all the way down to 0 PSI of boost at wide open throttle, as well as removing a bunch of timing to keep it safe, you’ll also get a CEL for fuel trims. Again this is safety, it's not something you should plan on doing, there is much more risk here that it will not turn down fast enough.



Quick overview of tunes and what fuels you can run in each and the expected power gains on a tune only vehicle near sea level.



Auto octane

87 octane - 0-10whp

89 octane - 20-30whp

91 octane - 30-45whp

93 octane - 35-55whp

E30 (mix of 93 and e85)- 45-70whp



91 octane

91 octane – 50-70whp

93 octane - 60-75whp

E30 (mix of 93 and e85)- 70-90whp



93

93 octane - 60-85whp

E30 (mix of 93 and e85) - 70-100whp



E50

E50 (mix of 91/93 and e85) - 90-140whp

On overall ethanol content can be 40-60% with the note that above 50% the ecu may have to reduce boost slightly as it comes up on the injectors flow safety.







Sent from my SM-S908U1 using Tapatalk
 

Explorer22ST

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#2
Recently there has been a lot of confusion on tunes and the difference between auto octane and dedicated tunes and what that means.



Auto octane is something the OEM strategy already does. In fact the ford advertised HP numbers are actually tested on 91 octane e10 fuel that is certified for the emissions testing. These ecus have closed loop timing, the ecu can add and subtract timing through the knock logic. The ecu will always try to keep the ignition timing on the borderline of spark knock that is heavily dependent on the fuel. What that means is when you fill up you ST on 87 octane a few things are going to happen. The ecu is going to see more knock retard and less overall timing, as it learns where the spark needs to be it translates this into something call a Knock Octane Modifier. The KOM is effectively the long term fuel trim of the spark world. Based on the KOM, the ecu will modify the base ignition timing and the boost level. In most cases you will not be making advertised HP numbers on 87 octane.



Our ZFG Racing Auto Octane Tune expands this capability allowing the ecu to add more boost and more ignition timing on higher grade fuels. That is where all the power comes from. That along with our killer trans tuning and few other things is what makes our tunes so fast. Our Auto Octane Tunes are setup for 87-93 octane (and any octane boosters beyond 93) as well as up to 30% ethanol.



So why if the ecu is capable of this great auto octane feature would you shut it off and make a dedicated 91 and 93 octane tunes?

The answer is, we don’t shut it off. ALL of our tunes 91/93/e50/e85 (heck even the 707awhp st and 855whp f150) maintain the auto octane features as a safety. We call our tunes dedicated, but the reality is that if you put the wrong fuel in they are going to turn themselves down. This is a key safety feature of our tunes, and from time to time I get customers asking why their car seems so much slower than it was. It only takes 2 seconds to look at the data log and see the KOM has reduces the octane level and overall power.



So if all of our tunes leave auto octane on, what is the difference and why shouldn’t you just get a 93 tune and run whatever fuel you want?

91/93/e50 tunes have some key differences from auto octane tunes. 91 and 93 have higher upper limits for boost and timing. This means that the difference between the lower end of the tune and the upper end of the is larger than the auto octane tune. The issues becomes that if you are on 93 octane and run it to E and fill up with 87 it takes time to adjust. 91 and 93 are, depending on mods, over 100hp higher than what should be run on 87 octane, especially on long pulls. There is risk that computer wont turn it down fast enough to accommodate the fuel change. The risk is small and this works great as a safety, but if you want the most powerful tunes possible on 91/93 the risk is there and it’s not something everyone should be doing on a daily basis. That’s why we have decided tunes.



E50 has more aggressive starting points for timing, higher upper limits for boost, fueling changes, as well as a bunch of other tweaks. The auto octane safety acts much more aggressively on this tune. If you put 87 octane or even 93 in on an e50 tune the ecu will bring the power potentially all the way down to 0 PSI of boost at wide open throttle, as well as removing a bunch of timing to keep it safe, you’ll also get a CEL for fuel trims. Again this is safety, it's not something you should plan on doing, there is much more risk here that it will not turn down fast enough.



Quick overview of tunes and what fuels you can run in each and the expected power gains on a tune only vehicle near sea level.



Auto octane

87 octane - 0-10whp

89 octane - 20-30whp

91 octane - 30-45whp

93 octane - 35-55whp

E30 (mix of 93 and e85)- 45-70whp



91 octane

91 octane – 50-70whp

93 octane - 60-75whp

E30 (mix of 93 and e85)- 70-90whp



93

93 octane - 60-85whp

E30 (mix of 93 and e85) - 70-100whp



E50

E50 (mix of 91/93 and e85) - 90-140whp

On overall ethanol content can be 40-60% with the note that above 50% the ecu may have to reduce boost slightly as it comes up on the injectors flow safety.







Sent from my SM-S908U1 using Tapatalk
Great info. Thanks for sharing.
 

dolsen

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#3
I love these technical write ups
 

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#4
I understood about 10-15% of that but my 93 Daily tune from ZFG is the tits. The dealer flashed me back to stock during a recent visit and I knew immediately something was wrong. Got home and flashed it back and there's a huge power difference.

Buy ZFG.
 

randyknight

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Chelsea, AL
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#5
Recently there has been a lot of confusion on tunes and the difference between auto octane and dedicated tunes and what that means.



Auto octane is something the OEM strategy already does. In fact the ford advertised HP numbers are actually tested on 91 octane e10 fuel that is certified for the emissions testing. These ecus have closed loop timing, the ecu can add and subtract timing through the knock logic. The ecu will always try to keep the ignition timing on the borderline of spark knock that is heavily dependent on the fuel. What that means is when you fill up you ST on 87 octane a few things are going to happen. The ecu is going to see more knock retard and less overall timing, as it learns where the spark needs to be it translates this into something call a Knock Octane Modifier. The KOM is effectively the long term fuel trim of the spark world. Based on the KOM, the ecu will modify the base ignition timing and the boost level. In most cases you will not be making advertised HP numbers on 87 octane.



Our ZFG Racing Auto Octane Tune expands this capability allowing the ecu to add more boost and more ignition timing on higher grade fuels. That is where all the power comes from. That along with our killer trans tuning and few other things is what makes our tunes so fast. Our Auto Octane Tunes are setup for 87-93 octane (and any octane boosters beyond 93) as well as up to 30% ethanol.



So why if the ecu is capable of this great auto octane feature would you shut it off and make a dedicated 91 and 93 octane tunes?

The answer is, we don’t shut it off. ALL of our tunes 91/93/e50/e85 (heck even the 707awhp st and 855whp f150) maintain the auto octane features as a safety. We call our tunes dedicated, but the reality is that if you put the wrong fuel in they are going to turn themselves down. This is a key safety feature of our tunes, and from time to time I get customers asking why their car seems so much slower than it was. It only takes 2 seconds to look at the data log and see the KOM has reduces the octane level and overall power.



So if all of our tunes leave auto octane on, what is the difference and why shouldn’t you just get a 93 tune and run whatever fuel you want?

91/93/e50 tunes have some key differences from auto octane tunes. 91 and 93 have higher upper limits for boost and timing. This means that the difference between the lower end of the tune and the upper end of the is larger than the auto octane tune. The issues becomes that if you are on 93 octane and run it to E and fill up with 87 it takes time to adjust. 91 and 93 are, depending on mods, over 100hp higher than what should be run on 87 octane, especially on long pulls. There is risk that computer wont turn it down fast enough to accommodate the fuel change. The risk is small and this works great as a safety, but if you want the most powerful tunes possible on 91/93 the risk is there and it’s not something everyone should be doing on a daily basis. That’s why we have decided tunes.



E50 has more aggressive starting points for timing, higher upper limits for boost, fueling changes, as well as a bunch of other tweaks. The auto octane safety acts much more aggressively on this tune. If you put 87 octane or even 93 in on an e50 tune the ecu will bring the power potentially all the way down to 0 PSI of boost at wide open throttle, as well as removing a bunch of timing to keep it safe, you’ll also get a CEL for fuel trims. Again this is safety, it's not something you should plan on doing, there is much more risk here that it will not turn down fast enough.



Quick overview of tunes and what fuels you can run in each and the expected power gains on a tune only vehicle near sea level.



Auto octane

87 octane - 0-10whp

89 octane - 20-30whp

91 octane - 30-45whp

93 octane - 35-55whp

E30 (mix of 93 and e85)- 45-70whp



91 octane

91 octane – 50-70whp

93 octane - 60-75whp

E30 (mix of 93 and e85)- 70-90whp



93

93 octane - 60-85whp

E30 (mix of 93 and e85) - 70-100whp



E50

E50 (mix of 91/93 and e85) - 90-140whp

On overall ethanol content can be 40-60% with the note that above 50% the ecu may have to reduce boost slightly as it comes up on the injectors flow safety.







Sent from my SM-S908U1 using Tapatalk
This is by far the best write up I've ever seen explain how the ECU makes these adjustments. I have tried to explain this to people for a few years now. Hopefully they will believe it coming from you. This thread should be a sticky with large bold headline and lined in gold!
 

UNBROKEN

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Adam, post that in HPEXST and I’ll make it a sticky.
 

st8

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Awesome write up, much appreciated. The ranges for the auto octane, is that based on other mods? So in an otherwise completely stock ST, the most I could pull using 93 would be 35hp? Or is still possible to pull up to 55hp pending other factors.

I’m so torn between the FP tune and the Zfg tune. I love the auto octane idea from Zfg and not being locked into premium fuel. Which is not the case for the FP tune.

I’m kinda leaning towards Zfg though now after reading this.
 

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#8
I’m so torn between the FP tune and the Zfg tune. I love the auto octane idea from Zfg and not being locked into premium fuel. Which is not the case for the FP tune.
Your ECU will adjust for the lower octane, FPP will not sell a tune that "LOCKS" you into premium fuel.
 

st8

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Your ECU will adjust for the lower octane, FPP will not sell a tune that "LOCKS" you into premium fuel.
Not true, according to the documents and a representative from ford performance. 91 octane and above must be used all the time according to them because there are no provisions for lower octane. A hole in the piston is the risk of not using premium.
 

UNBROKEN

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#10
Not true, according to the documents and a representative from ford performance. 91 octane and above must be used all the time according to them because there are no provisions for lower octane. A hole in the piston is the risk of not using premium.
Do you really think a Ford authorized tune would eliminate the very safeties that Adam made this whole thread about? Think about that for a minute and then think about the fact that most product representatives know very little about the product they’re representing.
 

st8

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#11
Do you really think a Ford authorized tune would eliminate the very safeties that Adam made this whole thread about? Think about that for a minute and then think about the fact that most product representatives know very little about the product they’re representing.
“ Premium Fuel Requirement: Customers who purchase power upgrade packs, cold air kits with calibration, engine calibrations, or superchargers are required to use 91-octane or higher ("premium") fuels at all times. Any failures associated with the non-use of premium fuel will be ineligible for warranty repair”.

Straight from the FP website. I’m sure there is some safety mechanism but Adams auto tune can legitimately be ran on 87. Minimal to no improvements but it can run 87. FP tune can’t.
 

UNBROKEN

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#12
Yes, it can. That’s a generic statement they send out with every tune they sell.
They didn’t eliminate the safety features inherent to the car. Be realistic.
 

st8

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Yes, it can. That’s a generic statement they send out with every tune they sell.
They didn’t eliminate the safety features inherent to the car. Be realistic.
Realistic? I’m purely reading exactly what ford performance themselves requires. It’s probably not like Zfg auto octane but rather the pure 91/93 tunes. Meaning you have to use premium but if you do use 87 for example, you’ll be okay but you shouldn’t use it continuously.
 

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#14
Hasn’t TMac already been trying to tell us this? lol :p
 

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#15
Yes, it can. That’s a generic statement they send out with every tune they sell.
They didn’t eliminate the safety features inherent to the car. Be realistic.
Gotta side up with Unbroken. If there is a failure with FP tune the first place FMOCO is going is to download the ECU. Not sure if they can see what oct. was used at the time of the failure, but a simple fuel check from the tank will give them a clue..Ford is the master in CYA, by stipulating premium only they're covered. Adam is crystal clear on the risks. He tweaks his dedicated tunes so when you're in BFE, and the only thing you can find is 87 you're covered as long as you keep your foot out of it. However if you continue to drive like Carl Edwards it's on you. I went with ZFG Auto Octane for a little lower risk. Butt dyno makes me believe I got a little more than adrertised 55 WHP, regardless, I'm completely satisfied with the results. I don't race it, I won't get into a pissing contest over Draggy times. Just smile when I get into the go peddle, and not worry too much about shelling the weak ass 6 series 10 sp transmission FOMOCO put in a 400 hp sport grocery getter rather than the 8 series they put in a highway queen Bronco. Just sayin
 

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Thread Starter #16
Do you really think a Ford authorized tune would eliminate the very safeties that Adam made this whole thread about? Think about that for a minute and then think about the fact that most product representatives know very little about the product they’re representing.
It actually wouldn't surprise me if that was the case based on past examples. Will need someone to read to tell for sure .

Sent from my SM-S908U1 using Tapatalk
 

st8

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I’m not saying ford doesn’t have some safety measure in place still, in the event someone doesn’t use premium. I’m saying the FP tune apparently is designed to run ONLY premium. Again, if you didn’t use it once, you’ll probably be okay but you shouldn’t use it all the time.

Adams auto octane, I could flash and run 87 forever and things would be just fine. That’s a big difference. And I really appreciate the design and setup Adam has accomplished. That’s why despite the comforting idea of a warranty, I’m still leaning towards Zfg.

@mwinn yeah I have similar feelings. I don’t want to drag race or any of that. I just want a little extra power and smiles. That’s all.
 

Last edited:
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#18
[QUOTE=" Just smile when I get into the go peddle, and not worry too much about shelling the weak ass 6 series 10 sp transmission FOMOCO put in a 400 hp sport grocery getter rather than the 8 series they put in a highway queen Bronco. Just sayin[/QUOTE]


The bronco uses the 10r60 as well.
 

Zim

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#19
I understood about 10-15% of that but my 93 Daily tune from ZFG is the tits. The dealer flashed me back to stock during a recent visit and I knew immediately something was wrong. Got home and flashed it back and there's a huge power difference.

Buy ZFG.
I swear. I’ve had them do this even going in for an oil change and I can feel the difference immediately. Skipping gears etc.
 

st8

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#20
I swear. I’ve had them do this even going in for an oil change and I can feel the difference immediately. Skipping gears etc.
Why is the dealer flashing you guys back to stock? Isn’t that really dangerous if the the dealer tries to update anything software related when you have a tune on board? Also, I thought it was always recommended to flash stock before going into the dealer. Purely curious from someone looking to tune.
 

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