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The third generation TL manual clearly states that only use of fuel below 87 octane leads to engine damage. 87 octane and above does not. There can be no counter arguments without data on this specific vehicle.
I collected RPM, load, timing, and IAT. For a given RPM and load, I have the timing. The plot I posted earlier was the difference between 87 and 93, averaged over RPMs, weighted equally for each RPM, meaning I have controlled the average difference for any changes in RPM distribution over each trip. It shows than when using 87, timing is retarded in comparison to 93, which is what we expect. But that timing retard occurs only for engine loads above about roughly 50% (and has been confirmed by other members). My other plots show timing is retarded with 91 in comparison to 93 as well, which is not what anyone originally knew, and demonstrates that the knock sensor is used to retard timing even when 91 octane fuel is used (the engine has no way of directly measuring octane without the knock sensor). If you believe my measurements are incorrect, then go make measurements yourself and post the data. Otherwise, your arguments are baseless. Back up your statements with data.
Going forward I will be collecting data in warmer weather to understand how IAT affects the timing between 87, 91, and 93.
CURRENT THREAD CONCLUSIONS SUMMARY:
Use of 91 octane for the third generation TL is "recommended" but not "required." (manufacturer input and 2006 owners manual)
Use of 87 octane fuel does not lead to engine damage. (based on input from the manufacturer and clearly stated in the 2006 owner's manual*)
Use of 87 octane fuel does not change engine characteristics below ~50% load (based on measured data from multiple users).
Above ~50% load, there is a loss of power using 87 octane compared to 91 or 93 octane (based on data and manufacturer).
The knock sensor is used to retard timing across all octane levels, depending on load and octane. (based on experimental data).
87 octane fuel costs 20% less than 93 in some areas of the nation. Current measurements of changes in MPG are negligible, if they occur at all. (partial data, still being collected)
MYTH: Using regular gas in a car designed for premium will definitely damage the engine.
We don't believe that any modern engine that claims to require premium will be damaged by using regular unleaded judiciously. Neither do any of the sources we've checked with - including the American Petroleum Institute, the American Engine Rebuilders Association - even a chemist (who would rather go unnamed) at a major gasoline company.
Last edited by RustyLogic; 02-12-2015 at 12:22 PM.
The third generation TL manual clearly states that only use of fuel below 87 octane leads to engine damage. 87 octane and above does not. There can be no counter arguments without data on this specific vehicle.
Everyone agrees that engine damage isn't guaranteed to occur. I mentioned this in my previous post and you ignored it.
I collected RPM, load, timing, and IAT. For a given RPM and load, I have the timing. The plot I posted earlier was the difference between 87 and 93, averaged over RPMs, weighted equally for each RPM, meaning I have controlled the average difference for any changes in RPM distribution over each trip. It shows than when using 87, timing is retarded in comparison to 93, which is what we expect. But that timing retard occurs only for engine loads above about roughly 50% (and has been confirmed by other members). My other plots show timing is retarded with 91 in comparison to 93 as well, which is not what anyone originally knew, and demonstrates that the knock sensor is used to retard timing even when 91 octane fuel is used (the engine has no way of directly measuring octane without the knock sensor). If you believe my measurements are incorrect, then go make measurements yourself and post the data. Otherwise, your arguments are baseless. Back up your statements with data.
Please upload your data file. I'll make the correct plot. I asked you for it in my previous post and you ignored it.
You know, if say, some of the pro-87ers ever own a Ferrari...? Lord help them if they disobey the owner's manual on the type of octane needed for the car.
I've said it before, if saving a few bucks is your MO...and within your right...why do it on something you need to be reliable and AGAINST the owner's manual? How about eat out less once a week?
Cuz, call me stupid or wasteful...but, I'm pouring minimum 91 grade octane into both my cars cuz well, instructions exist for a reason? Forget the technical stuff which I have zero interest to jump into and has been explained excellently by some of the peeps in here.
So...show of e-hands for a thread lock?
Or do we want to just see how long this thread can REALLY go?
The original intent of this thread was for users to be sharing data resulting from comparisons running their own vehicles on varying octanes of fuels. A few members stuck by that principle and contributed honestly to discussion.
There are no sides. We confirmed that timing is retarded in 87 vs 93. We interestingly discovered that knock sensors are used over all fuel octane levels. We discovered evidence that timing changes only occur at certain load ranges, which makes sense with the notion that increased pressure leads increased probability of pre-ignition. We discovered that language in the owner's manuals changed in 2006 to reflect that engine damage does not occur at octane levels of 87 octane and above. For me, I have learned a lot over the course of the thread, and I hope others have as well.
However, since then, due to others feeling insecure over their strongly held beliefs, it has digressed into, quick frankly, a zoo. This thread was not intended as a place for people to have their opinions validated. It was intended to share data in an attempt to, over time, answer questions and dispel common ignorance regarding the effects of fuel octane on third generation TL engines.
If this thread represents the true maximal quality of these forums, by all means, lock it. If however, we can revert back to reasoned sharing of data to improve everyone's knowledge, then leave it open. But I don't see that as being quite likely at this point.
CURRENT THREAD CONCLUSIONS SUMMARY:
Use of 91 octane for the third generation TL is "recommended" but not "required." (manufacturer input and 2006 owners manual)
Use of 87 octane fuel does not lead to engine damage. (based on input from the manufacturer and clearly stated in the 2006 owner's manual*)
Use of 87 octane fuel does not change engine characteristics below ~50% load (based on measured data from multiple users).
Above ~50% load, there is a loss of power using 87 octane compared to 91 or 93 octane (based on data and manufacturer).
The knock sensor is used to retard timing across all octane levels, depending on load and octane. (based on experimental data).
87 octane fuel costs 20% less than 93 in some areas of the nation. Current measurements of changes in MPG are negligible, if they occur at all. (partial data, still being collected)
Last edited by RustyLogic; 02-12-2015 at 01:58 PM.
^ RustyLogic...FWIW, that's why I asked if this thread needed to be locked.
Personally, I think it's run its course but given the length and level of detail some of the posts are going, obviously, it is not. Still, I think this topic is a bit played out. Anyhow, don't mind me...carry on!
Yeah, that last post was very well written out. I literally only do 93 because 91 is hard to come by down here and I would rather follow the manual on recommendations. Even with the Extended Performance Mobil 1 oil that claims 15K mile intervals...I'm only comfortable with 5.
Rusty, for all I know, my plot will actually support your conclusions. Why do you keep ignoring me?
I am not interested in getting you to agree with me. I don't care what fuel you use. I don't care what fuel anyone uses. I care about asking questions and finding answers.
If you don't want me to ignore you, do an experiment to test one of the conclusions. Post the data. If it is consistent with data posted previously, great. If it's not, we can try to find out why two different data sets are different. Until that time I have no interest in what you have to say.
If you would like suggestions on how to contribute, start with something easy: run a tank of 93, measure your MPG. Run a tank of 87 and do the same. Check your tire pressures regularly, and drive reasonably on both tanks. Post the results.
If you have an ECU scanner, measuring your timing in comparison to engine load, RPM, and IAT. Post the results.
If you want to help us better understand the exact loss of power, run some 0-60 experiments using both types of fuel. Post the results.
CURRENT THREAD CONCLUSIONS SUMMARY:
Use of 91 octane for the third generation TL is "recommended" but not "required." (manufacturer input and 2006 owners manual)
Use of 87 octane fuel does not lead to engine damage. (based on input from the manufacturer and clearly stated in the 2006 owner's manual*)
Use of 87 octane fuel does not change engine characteristics below ~50% load (based on measured data from multiple users).
Above ~50% load, there is a loss of power using 87 octane compared to 91 or 93 octane (based on data and manufacturer).
The knock sensor is used to retard timing across all octane levels, depending on load and octane. (based on experimental data).
87 octane fuel costs 20% less than 93 in some areas of the nation. Current measurements of changes in MPG are negligible, if they occur at all. (partial data, still being collected)
Last edited by RustyLogic; 02-12-2015 at 02:29 PM.
Contribute data to receive data. The more data the better.
CURRENT THREAD CONCLUSIONS SUMMARY:
Use of 91 octane for the third generation TL is "recommended" but not "required." (manufacturer input and 2006 owners manual)
Use of 87 octane fuel does not lead to engine damage. (based on input from the manufacturer and clearly stated in the 2006 owner's manual*)
Use of 87 octane fuel does not change engine characteristics below ~50% load (based on measured data from multiple users).
Above ~50% load, there is a loss of power using 87 octane compared to 91 or 93 octane (based on data and manufacturer).
The knock sensor is used to retard timing across all octane levels, depending on load and octane. (based on experimental data).
87 octane fuel costs 20% less than 93 in some areas of the nation. Current measurements of changes in MPG are negligible, if they occur at all. (partial data, still being collected)
But seriously, no I don't. I simply want to plot the data in a much more accurate representation on a 3D plot. I never challenged the accuracy of the data. At this point I'm completely dumbfounded by Rusty's response to my request of the data file considering his rampant "DATA OR GTFO" posts.
The original intent of this thread was for users to be sharing data resulting from comparisons running their own vehicles on varying octanes of fuels. A few members stuck by that principle and contributed honestly to discussion.
- Enlighten me please. All I've seen is you ignoring members that tried to be realistic with you. Except you ignored many and only listened to those that share the same mentality as yourself.
There are no sides.
-Clearly the joke is on all of us..
We
-Wrong.. YOU
confirmed that timing is retarded in 87 vs 93. We interestingly discovered that knock sensors are used over all fuel octane levels. Wediscovered evidence that timing changes only occur at certain load ranges, which makes sense with the notion that increased pressure leads increased probability of pre-ignition. We discovered that language in the owner's manuals changed in 2006 to reflect that engine damage does not occur at octane levels of 87 octane and above. For me, I have learned a lot over the course of the thread, and I hope others have as well.
-Again, enlighten me on what exactly YOU learned. It seems the only thing you learned to do is ignore everyone and stand by whatever results you came up with on your own.. You discredit all information if it points to using 91 or higher because it's not what you believe to be the right answer.
However, since then, due to others feeling insecure
-Biggest joke right here.. Really? others feeling insecure? Coming from the same person that wanted to "report" members..
over their strongly held beliefs, it has digressed into, quick frankly, a zoo. This thread was not intended as a place for people to have their opinions validated. It was intended to share data in an attempt to, over time, answer questions and dispel common ignorance regarding the effects of fuel octane on third generation TL engines.
If this thread represents the true maximal quality of these forums
-Welcome to Acurazine. You're new here. Certainly not new to having conversations with other humans, or do you just talk to yourself and have yourself answer yourself? Part of running a debate like this, is being able to listen and understand what others are saying. You have shut down and ignored others. This to my eyes represents that you are disrespectful and above everyone. Set an example of respect by showing respect to others. Simply don't start a thread and towards the end threaten to "Report" members just because it's not going YOUR way. This thread has been nothing but your ideas, thoughts, data , ect. all and all for you.
, by all means, lock it. If however, we can revert back to reasoned sharing of data to improve everyone's knowledge, then leave it open. But I don't see that as being quite likely at this point.
Some of you spend too much time on a subject you have no interest. But the more the merrier.
I'd be careful making any final conclusion based on small experiment.
Random thought to consider:
When air filter is clogged ECU in order to keep safe air/fuel ratio reduces fuel portion. By reducing fuel portion you have a greater risk of lean mixture, lean mixture runs hotter which lead to combustion. ECU cannot adjust timing for spontaneous combustion all it can do is increase fuel portion to make mixture rich.
Since a lot of A-zine members experienced heat soak leads me to believe that 3G TL is running on an edge of performance, and outside air temperature and density make a huge difference.
That means that engine's 50% threshold load will be different under different weather conditions.
I think there is safe territory during which 87 octane can be used without any issues but I wouldn't do this experiment during hot weather.
Some of you spend too much time on a subject you have no interest. But the more the merrier.
I'd be careful making any final conclusion based on small experiment.
Random thought to consider:
When air filter is clogged ECU in order to keep safe air/fuel ratio reduces fuel portion. By reducing fuel portion you have a greater risk of lean mixture, lean mixture runs hotter which lead to combustion. ECU cannot adjust timing for spontaneous combustion all it can do is increase fuel portion to make mixture rich.
Since a lot of A-zine members experienced heat soak leads me to believe that 3G TL is running on an edge of performance, and outside air temperature and density make a huge difference.
That means that engine's 50% threshold load will be different under different weather conditions.
I think there is safe territory during which 87 octane can be used without any issues but I wouldn't do this experiment during hot weather.
Yes ambient temperature makes a big difference! Our cars don't measure air flow into the engine directly but calculate it. It's a speed density system, I wouldn't call it, edge of performance.
Yes ambient temperature makes a big difference! Our cars don't measure air flow into the engine directly but calculate it. It's a speed density system, I wouldn't call it, edge of performance.
I think we can all agree that the only concrete conclusion we could possibly draw here is that this thread and a lot of these posts are good evidence as to why engineers rarely get laid and have few close friends.
I think we can all agree that the only concrete conclusion we could possibly draw here is that this thread and a lot of these posts are good evidence as to why engineers rarely get laid and have few close friends.
I gets all da pusssaaayyy.. and have hundreds of eFriends.
I wouldn't go that far with the 3rd bullet. Have we even ascertained that the input from the knock sensor is causing the adjustment of timing with 93? That seems to be only implied by the ignition timing adjustment. Timing is adjusted to RPM as well. I might have missed it but are we really plotting against engine load? What about against RPM? Somebody run some sunoco and plot that.
02-12-2015, 12:12 PM
Then maybe you should share your data [files].
start what?
