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92OCT and tuning....

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Portland
#1
Hi all,

Has anyone tried running a 93oct tune with 92oct? I just moved to Oregon and can now get 92 instead of 91 (woohoo, mind blown)!

If so, what were your results??

I know that in general, not to run any tune with lower than specified octane rating. However I read somewhere on this forum that OR's 92oct actually measures out to around 94oct.
Just looking for any first hand experiences :)
 


Messages
38
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33
Location
Portland
#4
You can try running your 93 tune here and see what kind of ignition correction and OAR you get. If you are consistently seeing an OAR number closer to +1 rather than -1, you will want to retune. If you are seeing consistent negative correction over about -1.5 degrees, you will want to retune. I worked with Randy at Mountune and there was significant room above the stock Mountune 91 tune. I now have mine pretty dialed in for 92. I use Fred Meyer 92 exclusively and have never had any problems. If you are seeing a ton of negative correction, you can run slot 4 or the 91 OTS tune until you can get retuned for 92.

Info on Knock: http://stratifiedauto.com/blog/unde...ons-in-your-high-performance-ecoboost-engine/
 


Messages
113
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59
Location
Oak Harbor
#5
danbfree has a write up on this in the performance section under 'what tune are you running' where he describes the resulting actual octane due to ethanol quantities in PNW gasoline. He suggests that the 10% Ethanol ups actaul octane to around 94. I have not tried this yet, but will be looking into it shortly. Can anyone explain how to monitor OAR? Is it a selectable field on the COBB AP?

Sent from my SM-G950U using Tapatalk
 


redmoe

Active member
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Phoenix
#6
Ethanol has an octane rating around 113. At a 10% ratio you are looking at .1*113+.9*92 yielding approx 94 octane. This is based on the source fuel being a consistent 10% which will vary throughout the seasons. The octane rating associated with OTS tunes is assuming a certain level of ethanol as the tune was created and tested using the specified octane from the pump which will have varying levels of ethanol. I would not count on the seasonal ethanol to bump your octane level in regard to the tune. You are better off just verifying little to no negative ignition and a solid -1 oar. If you see issues with the corrections or oar you can: 1. Run a tune that is for a lower octane rating. 2. Add a small amount of E85 or race fuel. 3. Get a custom tune for your situation.
 


redmoe

Active member
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#7
To monitor OAR you need to select it from the available pids in the AP gauge mode
 


Messages
38
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33
Location
Portland
#13
Ethanol has an octane rating around 113. At a 10% ratio you are looking at .1*113+.9*92 yielding approx 94 octane. This is based on the source fuel being a consistent 10% which will vary throughout the seasons. The octane rating associated with OTS tunes is assuming a certain level of ethanol as the tune was created and tested using the specified octane from the pump which will have varying levels of ethanol. I would not count on the seasonal ethanol to bump your octane level in regard to the tune. You are better off just verifying little to no negative ignition and a solid -1 oar. If you see issues with the corrections or oar you can: 1. Run a tune that is for a lower octane rating. 2. Add a small amount of E85 or race fuel. 3. Get a custom tune for your situation.
This is interesting. I was always under the impression that the octane rating was with the ethanol being taken into account. Granted, on the pump it does say that 92 is the "minimum octane rating". I do have a hard time believing that they would be providing 94 octane and not advertising it as such or charging us accordingly.

As far as seasonality octane rating, there may be something to be said for that. During the winter, on my current tune, I had much higher and more frequent negative ignition corrections from my slot 1 tune and had to switch to slot 4. I was going to have Randy send a lower-output tune to run and now that we are in spring/summer here I can run it with few problems. This is all anecdotal evidence but it worked for me.

I also second the E85 addition. When I was having trouble with negative correction, Randy suggest I run a gallon of E85 in my tank. I went to Jay's Garage (the only place in PDX that sells it) and put a gallon in. Lo and behold, all of my negative ignition corrections disappeared. If you are trying to isolate whether octane is causing you problems, E85 is a great way to test that.

I have not tried to run the Cobb 93 OTS tune here. I guess I could load it up and see what happens. Has anyone tried running a 93 tune here? I am curious to see what negative corrections and OAR you see.
 


redmoe

Active member
Messages
516
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247
Location
Phoenix
#14
This is interesting. I was always under the impression that the octane rating was with the ethanol being taken into account. Granted, on the pump it does say that 92 is the "minimum octane rating". I do have a hard time believing that they would be providing 94 octane and not advertising it as such or charging us accordingly.

As far as seasonality octane rating, there may be something to be said for that. During the winter, on my current tune, I had much higher and more frequent negative ignition corrections from my slot 1 tune and had to switch to slot 4. I was going to have Randy send a lower-output tune to run and now that we are in spring/summer here I can run it with few problems. This is all anecdotal evidence but it worked for me.

I also second the E85 addition. When I was having trouble with negative correction, Randy suggest I run a gallon of E85 in my tank. I went to Jay's Garage (the only place in PDX that sells it) and put a gallon in. Lo and behold, all of my negative ignition corrections disappeared. If you are trying to isolate whether octane is causing you problems, E85 is a great way to test that.

I have not tried to run the Cobb 93 OTS tune here. I guess I could load it up and see what happens. Has anyone tried running a 93 tune here? I am curious to see what negative corrections and OAR you see.
It would not be cost effective for the stations to change their labels for the ethanol variation through the seasons. Summer blends of fuel will typically have a lower ethanol percent to combat evaporation in the height summer heat. Winter blends have more ethanol to help with cold engine start and operation via lower temp evaporation.

You will notice that the ethanol content label also typically read “up to 10%” for this reason. Even E85 will vary seasonally to combat cold weather performance.

Long story short you should not rely on assumed octane ratings. You could very well end up with the published min.
 


Messages
113
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Location
Oak Harbor
#15
Update: stage 2 93oct COBB OTS Map works great. See poll thread for tune use for more info. No complaints, stable -1.00 OAR, stable Oil temps, Charge Air temps (ambient air at 60°F), and 4.7 AFR... Loving it!

...until danBfree talks me fully into a stratified tune! [emoji45]

Sent from my SM-G950U using Tapatalk
 


danbfree

3000 Post Club
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Location
Tigard, Oregon, USA
#16
Hi all,

Has anyone tried running a 93oct tune with 92oct? I just moved to Oregon and can now get 92 instead of 91 (woohoo, mind blown)!

If so, what were your results??

I know that in general, not to run any tune with lower than specified octane rating. However I read somewhere on this forum that OR's 92oct actually measures out to around 94oct.
Just looking for any first hand experiences :)
Ethanol has an octane rating around 113. At a 10% ratio you are looking at .1*113+.9*92 yielding approx 94 octane. This is based on the source fuel being a consistent 10% which will vary throughout the seasons. The octane rating associated with OTS tunes is assuming a certain level of ethanol as the tune was created and tested using the specified octane from the pump which will have varying levels of ethanol. I would not count on the seasonal ethanol to bump your octane level in regard to the tune. You are better off just verifying little to no negative ignition and a solid -1 oar. If you see issues with the corrections or oar you can: 1. Run a tune that is for a lower octane rating. 2. Add a small amount of E85 or race fuel. 3. Get a custom tune for your situation.
This is interesting. I was always under the impression that the octane rating was with the ethanol being taken into account. Granted, on the pump it does say that 92 is the "minimum octane rating". I do have a hard time believing that they would be providing 94 octane and not advertising it as such or charging us accordingly.

As far as seasonality octane rating, there may be something to be said for that. During the winter, on my current tune, I had much higher and more frequent negative ignition corrections from my slot 1 tune and had to switch to slot 4. I was going to have Randy send a lower-output tune to run and now that we are in spring/summer here I can run it with few problems. This is all anecdotal evidence but it worked for me.

I also second the E85 addition. When I was having trouble with negative correction, Randy suggest I run a gallon of E85 in my tank. I went to Jay's Garage (the only place in PDX that sells it) and put a gallon in. Lo and behold, all of my negative ignition corrections disappeared. If you are trying to isolate whether octane is causing you problems, E85 is a great way to test that.

I have not tried to run the Cobb 93 OTS tune here. I guess I could load it up and see what happens. Has anyone tried running a 93 tune here? I am curious to see what negative corrections and OAR you see.
Yes, yes and yes, our 92 is easily 93+ year round... only the few most populated counties in Oregon even change their fuel at all for summer/winter and only a little, with a 93 tune year round I stay buried at -1.00 OAR and all positive ignition corrections.... I started researching this back when I had an Audi so I'm happy to share the good news with you guys! And just a theory on rated at 92 before e10 was added, I just know it works with 93 tunes year round, but also is what tuners have theorized before... But this is also with the canned Cobb and Stratified tunes, maybe Randy with Mountune is going more aggressive on certain things and causing some ignition corrections, but definitely works for me with no issues, I just make sure to always use Top Tier, which isn't too hard when even Arco and Costco have it, just Safeway, Fred Meyer, Space Age, etc. maybe not using Fred Meyer which is not Top Tier is causing some issues for S_Manley, but can't believe anyone would not run Top Tier on a DI car.. Also, our fuel in WA/OR is oxygenated year round too, but even if ethanol dropped to only 5%, which it doesn't, would make it 93 octane, but again, tuners have confirmed we are more like 94 here, so that helps with my theory that it's 92 before e10 is added, which is cheaper anyway, so why would they charge more? LOL :)
 


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Location
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#17
Yes, yes and yes, our 92 is easily 93+ year round... only the few most populated counties in Oregon even change their fuel at all for summer/winter and only a little, with a 93 tune year round I stay buried at -1.00 OAR and all positive ignition corrections.... I started researching this back when I had an Audi so I'm happy to share the good news with you guys! And just a theory on rated at 92 before e10 was added, I just know it works with 93 tunes year round, but also is what tuners have theorized before... But this is also with the canned Cobb and Stratified tunes, maybe Randy with Mountune is going more aggressive on certain things and causing some ignition corrections, but definitely works for me with no issues, I just make sure to always use Top Tier, which isn't too hard when even Arco and Costco have it, just Safeway, Fred Meyer, Space Age, etc. maybe not using Fred Meyer which is not Top Tier is causing some issues for S_Manley, but can't believe anyone would not run Top Tier on a DI car.. Also, our fuel in WA/OR is oxygenated year round too, but even if ethanol dropped to only 5%, which it doesn't, would make it 93 octane, but again, tuners have confirmed we are more like 94 here, so that helps with my theory that it's 92 before e10 is added, which is cheaper anyway, so why would they charge more? LOL :)
I am at -1.00 OAR all the time as well. I do have some WOT ignition corrections but nothing major. I guess I could try and have Randy dial more of that out, but my OAR doesn't move even with the negative corrections. When I put my downpipe on and have Randy readjust for Stage 3 I will have it dialed in even more, or I will get a protune with Surgeline.

I have run Fred Meyer premium the entire time I have had the car. While Fred Meyer is not certified as Top-Tier, some of the articles I have read make it seem as if they use top-tier level detergents, just haven't paid the fees for certification, which is entirely possible. Now, this is the internet so I take all of that with a grain of salt.

I do know that Randy commented on how good the fuel was after looking at my first log. Now, he could've been expecting CA 91 octane and seen our fuel and been blown away. I am not sure. In the 3 1/2 years of owning my car, I have not had a single problem with Fred Meyer fuel. I haven't seen a compelling reason to switch to Chevron or Shell. I could go to Costco but I don't get my fuel points discount [wiggle].

Randy has calibrated my tune for the fuel here. I did have to have him reduce the spark to curb some of the ignition corrections. I could always run slot 4 if it gets to be too big of a problem.

For fun, I will try running Costco premium for a few months to see if that makes a difference.
 


danbfree

3000 Post Club
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Tigard, Oregon, USA
#18
I am at -1.00 OAR all the time as well. I do have some WOT ignition corrections but nothing major. I guess I could try and have Randy dial more of that out, but my OAR doesn't move even with the negative corrections. When I put my downpipe on and have Randy readjust for Stage 3 I will have it dialed in even more, or I will get a protune with Surgeline.

I have run Fred Meyer premium the entire time I have had the car. While Fred Meyer is not certified as Top-Tier, some of the articles I have read make it seem as if they use top-tier level detergents, just haven't paid the fees for certification, which is entirely possible. Now, this is the internet so I take all of that with a grain of salt.

I do know that Randy commented on how good the fuel was after looking at my first log. Now, he could've been expecting CA 91 octane and seen our fuel and been blown away. I am not sure. In the 3 1/2 years of owning my car, I have not had a single problem with Fred Meyer fuel. I haven't seen a compelling reason to switch to Chevron or Shell. I could go to Costco but I don't get my fuel points discount [wiggle].

Randy has calibrated my tune for the fuel here. I did have to have him reduce the spark to curb some of the ignition corrections. I could always run slot 4 if it gets to be too big of a problem.

For fun, I will try running Costco premium for a few months to see if that makes a difference.
Good points, Freddies may run Top Tier level additives but just not pay for the certification and we know the label itself is just marketing, good call in at least looking into it! Since I do get cash back on Costco gas and it's even cheaper than Arco it's a no brainer for me. :)

Anyway, I'm glad I could provide a little feedback and good to hear it's working out for you guys, I DO have a 91 tune map as well, just in case our gas doesn't agree with 93, even one bad tank or I drive down to Cali, but nice to know we have extra sitting there over a 91 tune! :)
 


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