A new analysis of Premium vs. Regular
01-26-2015 | 07:46 AM
#41
As we know, from the owner's manual:
Your Acura is designed to operate on unleaded gasoline with a pump octane number of 91 or higher. Use of a lower octane gasoline can cause occasional metallic knocking noises in the engine and will result in decreased engine performance.
As it doesn't say recommended, I'd assume to receive the best performance it would be prudent to use at least 91 octane fuel. Would not using this grade do any harm, probably not, especially if one doesn't beat the car, just the lack of 100% performance, but I believe that under certain circumstances the knock sensor can't react fast enough to assure a 100% knock free engine. In fact, Honda states that in the 6 MT when the car is lugging, low RPM in a higher gear, there will be a knock and to shift to a lower gear.
I, like others stick by the manufacturer's recommendation and never think otherwise, but some like to deviate as they change from the recommended ATF, motor oil, etc, so why not fuel octane. Hey, if one wants to use a lower grade fuel, so be it, but changing my mind by posting numerous documents certainly isn't going to do the job.
Just an example of using a lower than recommended fuel octane.
Daughter's 2000 Maxima (purchased 2002, 31k miles) that has a recommended octane rating of 91, but she has always used 87 and now with 240k miles, the car runs as new, but she certainly isn't hard on the car.
I do have an older turbocharged car with a knock sensor, but the sensor can't react fast enough to compensate for the lower octane, so premium it must be.
To each their own.
Your Acura is designed to operate on unleaded gasoline with a pump octane number of 91 or higher. Use of a lower octane gasoline can cause occasional metallic knocking noises in the engine and will result in decreased engine performance.
As it doesn't say recommended, I'd assume to receive the best performance it would be prudent to use at least 91 octane fuel. Would not using this grade do any harm, probably not, especially if one doesn't beat the car, just the lack of 100% performance, but I believe that under certain circumstances the knock sensor can't react fast enough to assure a 100% knock free engine. In fact, Honda states that in the 6 MT when the car is lugging, low RPM in a higher gear, there will be a knock and to shift to a lower gear.
I, like others stick by the manufacturer's recommendation and never think otherwise, but some like to deviate as they change from the recommended ATF, motor oil, etc, so why not fuel octane. Hey, if one wants to use a lower grade fuel, so be it, but changing my mind by posting numerous documents certainly isn't going to do the job.
Just an example of using a lower than recommended fuel octane.
Daughter's 2000 Maxima (purchased 2002, 31k miles) that has a recommended octane rating of 91, but she has always used 87 and now with 240k miles, the car runs as new, but she certainly isn't hard on the car.
I do have an older turbocharged car with a knock sensor, but the sensor can't react fast enough to compensate for the lower octane, so premium it must be.
To each their own.
The following 2 users liked this post by Turbonut:
Acura-OC (01-26-2015),
truonghthe (01-26-2015)
01-26-2015 | 09:49 AM
#42
Racer
Joined: Jun 2012
Posts: 252
Likes: 27
No way I would risk damaging my engine over a few dollars a fill up (even if its $5+). Acura says its required, so that's what I use.
My understanding of running lower octane fuel has already been stated on here. Knocking has to occur for the sensor to pull timing to prevent any further damage. By this time, it's already too late.
I have a friend with a early 90's legend who refuses to use 91+ octane fuel saying it makes no difference. I explained to him why it does matter, he shrugs it off. Frankly, I don't think it's worth the risk but if they want to run 87 in their cars, have at it.
My grand prix knocked straight from the factory. Running premium eliminated the knock (along with some exhaust mods).
If you can afford a "luxury" vehicle, just buy premium and be done with it.....
My understanding of running lower octane fuel has already been stated on here. Knocking has to occur for the sensor to pull timing to prevent any further damage. By this time, it's already too late.
I have a friend with a early 90's legend who refuses to use 91+ octane fuel saying it makes no difference. I explained to him why it does matter, he shrugs it off. Frankly, I don't think it's worth the risk but if they want to run 87 in their cars, have at it.
My grand prix knocked straight from the factory. Running premium eliminated the knock (along with some exhaust mods).
If you can afford a "luxury" vehicle, just buy premium and be done with it.....
01-26-2015 | 10:09 AM
#43
^ my sister did this to her legend when we were in high school. Her engine started knocking and behaving oddly. My other sister never changed her oil and her motor failed.
Since that time I've considered it bad woman logic to put regular in a high compression motor.
Since that time I've considered it bad woman logic to put regular in a high compression motor.
The following users liked this post:
TacoBello (01-26-2015)
01-26-2015 | 10:52 AM
#45
Senior Moderator
Joined: Apr 2010
Posts: 47,400
Likes: 8,800
From: SoCal, CA
Hey guys, I use 20W-50 in my TL because it's thicker and that means it lasts longer. I go about 50K miles in between oil changes too. RTFM comes to mind.. it's there for a reason, if you want to go against the grain and mess with your own car, be our guest. You can also run your car on pure water instead of coolant, it's much cheaper, you'll just have to fill water more often, but it's free at the gas station right? Fill up your 87 along with your water in your radiator!
"Just because you can, doesn't mean you should"...
"Just because you can, doesn't mean you should"...
The following users liked this post:
DMZ (01-26-2015)
01-26-2015 | 11:45 AM
#46
Team Owner
Joined: Jun 2014
Posts: 30,487
Likes: 4,416
From: In an igloo
All the turbo guys I know monitor for knock and they all say, even though you can't always hear it, it doesn't mean it's not happening.
A higher octane gasoline burns cleaner. Cleaner burning gas means cleaner emissions, and less carbon build up inside your engine. In Europe, in many places, their "regular" gas is 95 octane and premium is 98. Keep in mind, their numbers are derived from a different scale than ours (of course.. Why keep it simple). It's RON (research octane number- Europe) vs AKI (anti knock index- America)
AKI = RON x 0.95
By that process, Europe uses what we would consider 90 and 93. They don't even allow 87 because it's, well, shit.
01-26-2015 | 11:47 AM
#48
Team Owner
Joined: Jun 2014
Posts: 30,487
Likes: 4,416
From: In an igloo
By the way, after I finish deep frying some French fries at home, I like to reuse the vegetable oil in my engine. I mean, oil is oil and I'm saving a butt load of money by doing so.
By the way, on an unrelated topic- my car was running just fine and then shut off. Now the engine won't even turn over. Does anyone know why?
By the way, on an unrelated topic- my car was running just fine and then shut off. Now the engine won't even turn over. Does anyone know why?
01-26-2015 | 11:53 AM
#49
Senior Moderator
Joined: Apr 2010
Posts: 47,400
Likes: 8,800
From: SoCal, CA
By the way, after I finish deep frying some French fries at home, I like to reuse the vegetable oil in my engine. I mean, oil is oil and I'm saving a butt load of money by doing so.
By the way, on an unrelated topic- my car was running just fine and then shut off. Now the engine won't even turn over. Does anyone know why?
By the way, on an unrelated topic- my car was running just fine and then shut off. Now the engine won't even turn over. Does anyone know why?
01-26-2015 | 11:56 AM
#50
Team Owner
Joined: Jun 2014
Posts: 30,487
Likes: 4,416
From: In an igloo
Oh, ok, thanks man! I was thinking I might have mixed something up. So to get the old French fry oil out, can I simply just add some dish detergent in and rev the engine to redline to make sure it gets in every nook and cranny?
01-26-2015 | 11:59 AM
#51
Senior Moderator
Joined: Apr 2010
Posts: 47,400
Likes: 8,800
From: SoCal, CA
Yeah just make sure it's Dawn Platinum.. Don't use any of that regular dish detergent bullshit.. it'll ruin your engine.
Costco Business Delivery - Dawn Advanced Power Dish Soap, 90 oz
Costco Business Delivery - Dawn Advanced Power Dish Soap, 90 oz
01-26-2015 | 12:01 PM
#52
Team Owner
Joined: Jun 2014
Posts: 30,487
Likes: 4,416
From: In an igloo
I know the owners manual says to use "premium", but can't I just get away with regular detergent?
I mean, I know it says "required", but I think they're trying to fool us.
A room full of engineers < me
I mean, I know it says "required", but I think they're trying to fool us.
A room full of engineers < me
01-26-2015 | 12:01 PM
#53
Race Director
Joined: Dec 2003
Posts: 12,474
Likes: 1,795
From: MAGA country
Absolutely, but that's never been an argument. Once again, you totally miss the facts of my original question: If there is no knock, how can 87 damage an engine?
Supporting documentation?
Supporting documentation?
01-26-2015 | 12:12 PM
#54
Team Owner
Joined: Jun 2014
Posts: 30,487
Likes: 4,416
From: In an igloo
How do you know there's no knock? Based on what? If there is no knock, hence comes in the knock sensor which retards timing. Doing so WILL rob power. So in the end, guys drop thousands on MOAR POWER mods, only to take it all away buy running shit because it saves them $34.50 over the course of a month.
Try looking up any of the scientific papers showing that higher octane burns cleaner.
01-26-2015 | 12:13 PM
#55
Racer
Joined: Jul 2012
Posts: 428
Likes: 67
RustyLogic somewhere on first page provided link to a video with lab test results.
Mobil uses same amount of detergent in both 87 and 91 but who cares it is just lab results.
By the way in Europe you also can get 91 or 92 which is equivalent to 87
01-26-2015 | 12:17 PM
#56
Senior Moderator
Joined: Apr 2010
Posts: 47,400
Likes: 8,800
From: SoCal, CA
How do you know there is no knock if like Taco said, knock isn't always audible?
This sounds like:
"If a tree falls in the wood and no one is around to hear it, does it make a sound?"
Quoted from: Paying a Premium for High Octane Gasoline? | Consumer Information
"What's the right octane level for your car?
Check your owner's manual. Regular octane is recommended for most cars. However, some cars with high compression engines, like sports cars and certain luxury cars, need mid-grade or premium gasoline to prevent knocking."
I can't believe this thread is still going on. Just read your manual. Whether or not you decide to listen to it is ultimately your decision.
This sounds like:
"If a tree falls in the wood and no one is around to hear it, does it make a sound?"
Quoted from: Paying a Premium for High Octane Gasoline? | Consumer Information
"What's the right octane level for your car?
Check your owner's manual. Regular octane is recommended for most cars. However, some cars with high compression engines, like sports cars and certain luxury cars, need mid-grade or premium gasoline to prevent knocking."
I can't believe this thread is still going on. Just read your manual. Whether or not you decide to listen to it is ultimately your decision.
01-26-2015 | 12:18 PM
#57
Race Director
Joined: Dec 2003
Posts: 12,474
Likes: 1,795
From: MAGA country
Sigh....Go back and read post #10....and post #16...
Which of these paper/s did you read to come to this conclusion?
Which of these paper/s did you read to come to this conclusion?
Last edited by nfnsquared; 01-26-2015 at 12:22 PM.
01-26-2015 | 12:20 PM
#58
Race Director
Joined: Dec 2003
Posts: 12,474
Likes: 1,795
From: MAGA country
01-26-2015 | 12:49 PM
#60
Head a da Family
Joined: Jul 2003
Posts: 5,505
Likes: 563
From: New Friggin Jerzy
01-26-2015 | 12:55 PM
#61
Team Owner
Joined: Jun 2014
Posts: 30,487
Likes: 4,416
From: In an igloo
And yes, I'll start digging up the scientific papers I had to read in order to complete my various reports I had to do whilst getting my engineering degree, ten years ago.
for fuck sakes...
The following users liked this post:
04WDPSeDaN (01-26-2015)
01-26-2015 | 12:56 PM
#62
Team Owner
Joined: Jun 2014
Posts: 30,487
Likes: 4,416
From: In an igloo
01-26-2015 | 12:59 PM
#63
01-26-2015 | 01:04 PM
#64
Race Director
Joined: Dec 2003
Posts: 12,474
Likes: 1,795
From: MAGA country
Again, I'm not arguing whether or not 87 will/won't cause knocking. Again, what I'm asking is if there is zero induced knock, how could running 87 (or any octane lower than 91) cause engine damage? That's all I've asked.
Keep it civil please.
01-26-2015 | 01:19 PM
#65
Chapter Leader (Southern Region)
Joined: Sep 2008
Posts: 88,888
Likes: 11,843
From: Waffles, BU
01-26-2015 | 01:25 PM
#66
Chapter Leader (Southern Region)
Joined: Sep 2008
Posts: 88,888
Likes: 11,843
From: Waffles, BU
01-26-2015 | 01:27 PM
#67
Chapter Leader (Southern Region)
Joined: Sep 2008
Posts: 88,888
Likes: 11,843
From: Waffles, BU
I'll also add that some of the writers of these articles regarding going cheap at the pump have a kindergarten education in automotive engineering, if that. Some poster shared an article on Yahoo or some highly visible site. The writer went on to say that modern cars can handle knock and reduce such pesky noises.
01-26-2015 | 01:49 PM
#69
Race Director
Joined: Dec 2003
Posts: 12,474
Likes: 1,795
From: MAGA country
No argument there. If one chooses not to run Top Tier gas, then they may or may not be buying gas with sufficient detergent additives...
01-26-2015 | 02:35 PM
#70
Chapter Leader (Southern Region)
Joined: Sep 2008
Posts: 88,888
Likes: 11,843
From: Waffles, BU
Inacc had all types of setups including catless, meth and nitrous. I can't remember what he was running at the time. It's in one of his hundreds of threads. Aside from Inacc, others have datalogged the same but I can't remember being years ago. I believe inacc even put in a tank of 87 and 91 as a baseline and showed much more activity than 92/93.. so it is present. Good reads if you can find all of them and have time.
01-26-2015 | 05:08 PM
#71
It's beyond beating a dead horse at this point again. To understand knock/pinging someone has to understand how an engine works. Then study fuel and it's quality. Then the understanding of electronic controls with inputs from sensors. A person here posted a PDF of 380+ pages of how engines work, read up on it. I posted a few links with solid information. To ask the same question that has been answered is nauseating. At this point, nobody can hold someone's hand and say "Here billy this is fire, it burns, don't put your hand there". Must learn on your own.
/Thread.
/Thread.
The following users liked this post:
TacoBello (01-26-2015)
01-26-2015 | 05:20 PM
#72
Senior Moderator
Joined: Dec 2001
Posts: 167,734
Likes: 23,026
I have yet to meet one mechanic, experienced car guy come up to me and say to dump regular gasoline into my cars esp. if the vehicle requires premium.
I mean, to whoever believes using lower-grade fuel can help save a few bucks...cool? But, seriously, you can find savings in other parts of your life?
I mean, to whoever believes using lower-grade fuel can help save a few bucks...cool? But, seriously, you can find savings in other parts of your life?
The following users liked this post:
Majofo (01-27-2015)
01-26-2015 | 05:43 PM
#75
Race Director
Joined: Dec 2003
Posts: 12,474
Likes: 1,795
From: MAGA country
I went back and didn't see any links?
You posted that carbon build up is bad, something we all know. You posted that DI engines are notorious for carbon build up, which we all know.
Carbon build up is due to inferior detergent type and levels in gas, not octane rating. I'm not sure how your discussion of carbon build up relates to running lower octane gas?
Exactly what question is that? I believe I'm the only one that has asked a specific question, to which I already know the answer.
The question I have asked is this: If lower octane gas (less than 91) induces zero knock, how could it damage our engines? The answer: if zero knock is induced, it can't.
You posted that carbon build up is bad, something we all know. You posted that DI engines are notorious for carbon build up, which we all know.
Carbon build up is due to inferior detergent type and levels in gas, not octane rating. I'm not sure how your discussion of carbon build up relates to running lower octane gas?
Exactly what question is that? I believe I'm the only one that has asked a specific question, to which I already know the answer.
The question I have asked is this: If lower octane gas (less than 91) induces zero knock, how could it damage our engines? The answer: if zero knock is induced, it can't.
Last edited by nfnsquared; 01-26-2015 at 05:45 PM.
01-26-2015 | 05:53 PM
#76
Senior Moderator
Joined: Feb 2006
Posts: 20,941
Likes: 2,021
From: Space Coast, FL
My hypothesis right now based on articles that I've read (CarTalk, Google Scholar, etc) is that vehicle manufacturers use the words "recommended" vs. "required" according to both engine design and assumed operating environments, and whether or not spark retarding can prevent knock under all possible operating conditions.
For example, manufacturer might assume the vehicle to be operated between -20 F to 120 F. Altitudes -300 ft to 12,000 ft. Weight loads +80lbs to +1,000 lbs. (For typical consumer).
If a high compression engine design with the knock sensor permits the vehicle to operate without knock in the full range of conditions by adjusting timing, then the manufacturer puts the label "91 recommended."
If the engine design with the knock sensor permits the vehicle to operate without knock in a subset of the full range of conditions, then the manufacturer puts the label "91 required."
As an observation, if you examine the new 2015 TLX, there are two engine types:
Compression 11.6:1: 4-cyl.
Compression 11.5:1: V-6 & SH-AWD
The 4 cylinder engine has a fuel label "91 recommended." The V-6 has a fuel label "91 required," even though its compression ratio is technically smaller. They both use the same mechanisms to compensate for varying octane number and operating environments: knock sensor with spark retarding. However, the V-6 model is also 300 lbs heavier than the 4 cylinder model. I'm sure its operating temperatures may also be higher than the 4 cylinder, since I assume 6 cylinders generate more heat than 4.
So obviously, compression ratio is not the only mechanism at play. If added weight and heat means the vehicle can operate without knock only between -20 F to 80 F and easy driving (reduced heat generation), instead of the full range of -20 F to 120 F and intense driving, the manufacturer would write "91 required" as opposed to "recommended".
So in summary, I believe that if your engines operating conditions (easy driving, high altitude, or cold temperatures) are within the range that either knock is altogether avoided, or the engine can compensate through timing and knock sensor usage, no long term engine damage occurs, and your vehicle is fine running on regular 87 octane.
Some top-tier gas stations put the same amount of engine cleaners in their 87 octane as in their 93, as well. Mobil is one such station:
Which gasoline is best for mileage, your car's engine and your wallet? - ABC15 Arizona
Mobil even advertises that the only difference between their 87 octane fuel and 93 octane fuel is the octane level:
Types of Gasoline at Exxon and Mobil Stations | Exxon and Mobil
The difference between 87 and 93 here is $0.60 per gallon. If one can reasonably conclude that under their specific operating conditions knock will not occur, even without the knock sensor retarding timing (because it's cold, high altitude, or easy driving), and the fuel detergents are the same between 87 and 93, it is unlikely that use of 87 octane fuel would cause any engine damage whatsoever.
For example, manufacturer might assume the vehicle to be operated between -20 F to 120 F. Altitudes -300 ft to 12,000 ft. Weight loads +80lbs to +1,000 lbs. (For typical consumer).
If a high compression engine design with the knock sensor permits the vehicle to operate without knock in the full range of conditions by adjusting timing, then the manufacturer puts the label "91 recommended."
If the engine design with the knock sensor permits the vehicle to operate without knock in a subset of the full range of conditions, then the manufacturer puts the label "91 required."
As an observation, if you examine the new 2015 TLX, there are two engine types:
Compression 11.6:1: 4-cyl.
Compression 11.5:1: V-6 & SH-AWD
The 4 cylinder engine has a fuel label "91 recommended." The V-6 has a fuel label "91 required," even though its compression ratio is technically smaller. They both use the same mechanisms to compensate for varying octane number and operating environments: knock sensor with spark retarding. However, the V-6 model is also 300 lbs heavier than the 4 cylinder model. I'm sure its operating temperatures may also be higher than the 4 cylinder, since I assume 6 cylinders generate more heat than 4.
So obviously, compression ratio is not the only mechanism at play. If added weight and heat means the vehicle can operate without knock only between -20 F to 80 F and easy driving (reduced heat generation), instead of the full range of -20 F to 120 F and intense driving, the manufacturer would write "91 required" as opposed to "recommended".
So in summary, I believe that if your engines operating conditions (easy driving, high altitude, or cold temperatures) are within the range that either knock is altogether avoided, or the engine can compensate through timing and knock sensor usage, no long term engine damage occurs, and your vehicle is fine running on regular 87 octane.
Some top-tier gas stations put the same amount of engine cleaners in their 87 octane as in their 93, as well. Mobil is one such station:
Which gasoline is best for mileage, your car's engine and your wallet? - ABC15 Arizona
Mobil even advertises that the only difference between their 87 octane fuel and 93 octane fuel is the octane level:
Types of Gasoline at Exxon and Mobil Stations | Exxon and Mobil
The difference between 87 and 93 here is $0.60 per gallon. If one can reasonably conclude that under their specific operating conditions knock will not occur, even without the knock sensor retarding timing (because it's cold, high altitude, or easy driving), and the fuel detergents are the same between 87 and 93, it is unlikely that use of 87 octane fuel would cause any engine damage whatsoever.
If anyone doesn't have anything productive to add then don't post. Acurazine does not tolerate insults or attacks on other members.
Recommended vs required is multifaceted. It comes down to legal reasons, advertising reasons and as well engineering reasons.
First of all we are comparing Apples to oranges because the TLX is Direct Injection compared to Our Port Injection in the 3G and 4G TL. Also the 4cyl is DOHC compared to SOHC V6's used in the TLX, 3G and 4G TL. These differences alone makes a large impact as fuel/air mixtures can be better controlled with DI vs PI and as well with DOHC over SOHC.
Despite the method of injection and DOHC/SOCH you can end up with a slightly richer 87 mixture that can causes no knock, or you can end up with a 87 mixture that causes knock, or a leaner 87 mixture that causes knock. In 2 of these 3 scenarios, there is knock and the engine responds AFTER it hears the initial knock. Only the computer can sense the knock initially; audible knocking to human ears means that the engine has maxed out it's ability to prevent knock. With that said, any sort of Knock is not good as that means the fuel is igniting prematurely and putting a LARGE, UNTIMED load onto the rods, pins and piston when it shouldn't be.
You are correct in assuming that driving parameters do have a huge impact. Yes, driving in colder weather should reduce knock for the first few minutes until the engine warms up to operating temp, and then the effect of cooler air start to decrease as the engine is heating up the incoming air. Is this effect enough to overcome knock when using 87, maybe, maybe not. The only real way to know is to hook up a scanner and get real world results.
Driving the 3GTL and 4G TL in FL heat in traffic, I easily notice heat soak and when the car is starting to loose power, and this is while using 93 octane. I can only imagine the situation with using 87 octane. I have had to use 87 octane in my TL in the past and I've gotten horrible MPG while doing so; enough to the point where I spent more in fuel with 87 than I would have with 93.
Additives help fuel quality and how it burns (cleaner hopefully) but I've found most stations don't use the proper amount of additive even in major cities (Miami for example). I use Redline SI-1 Fuel Cleaner every so often rather than worry about using Chevron and hoping it has the additive in premium fuel. At the end of the day, it's the OCTANE rating that matters since that has a direct correlation to the amount of denotation (knocking) the engine has.
Your math is your first post seems to be somewhat accurate, however you don't account for unforseen variables such as traction on the ground with snow, humidity level, etc that are all tied into the tuning map in the car's ECU.
The following 3 users liked this post by csmeance:
01-26-2015 | 06:14 PM
#77
I went back and didn't see any links?
You posted that carbon build up is bad, something we all know. You posted that DI engines are notorious for carbon build up, which we all know.
Carbon build up is due to inferior detergent type and levels in gas, not octane rating. I'm not sure how your discussion of carbon build up relates to running lower octane gas?
Exactly what question is that? I believe I'm the only one that has asked a specific question, to which I already know the answer.
The question I have asked is this: If lower octane gas (less than 91) induces zero knock, how could it damage our engines? The answer: if zero knock is induced, it can't.
You posted that carbon build up is bad, something we all know. You posted that DI engines are notorious for carbon build up, which we all know.
Carbon build up is due to inferior detergent type and levels in gas, not octane rating. I'm not sure how your discussion of carbon build up relates to running lower octane gas?
Exactly what question is that? I believe I'm the only one that has asked a specific question, to which I already know the answer.
The question I have asked is this: If lower octane gas (less than 91) induces zero knock, how could it damage our engines? The answer: if zero knock is induced, it can't.
You are still missing the entire picture which is why people like TacoCat and myself have pretty much answered your question. I mentioned carbon because it's a greater result of using 87 octane which in return causes symptoms that will cause knock and eventually accelerated engine wear due to many other reasons as I posted before. What engine do you want to talk about with knock? Again, how do you know if knock is present or not? 87 will certainly have a greater chance to knock over 93. Again, this was started in the 3rd gen TL section. We know the TL has a high compression engine. We know what fuel is recommended. Its hard to tell someone who hasn't studied in the automotive industry about these topics. There's a lot of understanding of the engine, fuel, ecu and timing, sensors ect to understand why your question goes beyond simple explanation
.
01-26-2015 | 06:20 PM
#78
Race Director
Joined: Dec 2003
Posts: 12,474
Likes: 1,795
From: MAGA country
You are still missing the entire picture which is why people like TacoCat and myself have pretty much answered your question. I mentioned carbon because it's a greater result of using 87 octane which in return causes symptoms that will cause knock and eventually accelerated engine wear due to many other reasons as I posted before. What engine do you want to talk about with knock? Again, how do you know if knock is present or not? 87 will certainly have a greater chance to knock over 93. Again, this was started in the 3rd gen TL section. We know the TL has a high compression engine. We know what fuel is recommended. Its hard to tell someone who hasn't studied in the automotive industry about these topics. There's a lot of understanding of the engine, fuel, ecu and timing, sensors ect to understand why your question goes beyond simple explanation
.
.
I know of no study that proves that 87 octane gas produces more carbon build up than higher octanes and you have yet to provide any documentation to support your claim. I'd like anyone to show me such documentation.
01-26-2015 | 06:25 PM
#79
You haven't answered my question at all. It's already been answered by myself and others such as Majofo: if there's no knock, there's no damage.
I know of no study that proves that 87 octane gas produces more carbon build up than higher octanes and you have yet to provide any documentation to support your claim. I'd like anyone to show me such documentation.
I know of no study that proves that 87 octane gas produces more carbon build up than higher octanes and you have yet to provide any documentation to support your claim. I'd like anyone to show me such documentation.
01-26-2015 | 06:34 PM
#80
Racer
Joined: Aug 2012
Posts: 422
Likes: 39
From: Newport News, VA
Yes, if.
What I don't understand is why people try to justify using 87 instead of premium. You really, really don't pay that much more for it at the end of the day.
That having been said, why question professional engineers? Getting that engineering degree ain't easy, and becoming a P.E is even harder. If nothing else, paying the infinitesimally smaller amount for premium over the life of the vehicle is cheap insurance and will help you sleep better at night.
What I don't understand is why people try to justify using 87 instead of premium. You really, really don't pay that much more for it at the end of the day.
That having been said, why question professional engineers? Getting that engineering degree ain't easy, and becoming a P.E is even harder. If nothing else, paying the infinitesimally smaller amount for premium over the life of the vehicle is cheap insurance and will help you sleep better at night.
Last edited by Yikes; 01-26-2015 at 06:37 PM.