Premium or regular gas?

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Old Oct 19, 2016 | 03:39 AM
  #1  
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Premium or regular gas?

'09 TL.

Since purchasing it new I've used Premium gas, as that is specified.
Was told the timing will be negatively affected if I use regular.

After all these years, began wondering if others are using regular successfully.

Opinions/experiences?

Thanks.
Old Oct 19, 2016 | 06:30 AM
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your assumption of the ECU scaling back the timing to preserve the engine is correct.

this engine was made to get the snot beat out of it. IT LOVES to REV! so in fact, that it makes PEAK power at 7,000 RPM!!!
the Honda engineers have created a high strung engine that LOVES premium fuel!!!!!

over time, using regular fuel will be detrimental to the car. when will that happen? who knows? people have ran these engines up to 500k miles and beyond.
it's just safe to abide by the manufactures rules.
Old Oct 19, 2016 | 09:46 AM
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Our engines operate on high compression and dialing back the timing can only do so much to prevent early detonation and probable engine damage. Otherwise ALL engines would be of high compression and the timing could be manipulated by the ECU to control and prevent early detonation. I concur with the jitterbugging crab dude above, use what the manufacturer recommends.
Old Oct 19, 2016 | 09:49 AM
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First you kill Lincoln, now you're trying to kill your car?!


Just stick to Premium bud
Old Oct 19, 2016 | 12:08 PM
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Premium. Yes.

We need some kind of FAQ/sticky thread in most of these sections....seems like same questions being asked every 1-2 weeks....
Old Oct 19, 2016 | 12:50 PM
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its not rocket science, more like chemical engineering. but manufacturers recommend certain fuel grades for a reason.

the issue i see is when reports like the one AAA put out in September this year stating:AAA Finds Millions Of Drivers Waste Money On Premium Gas

AAA: Premium Gasoline Is A Waste Of Money For Many Drivers : NPR

HOWEVER people see the headline and think oh ok i should stop using premium, but reading the report CLEARLY states that this is only for drivers using premium in a car where the recommended fuel is Regular.....

For your TL - Stick to top tier premium and you will be fine. Other cars not required to run premium....use top tier and you will be fine.
Old Oct 19, 2016 | 12:55 PM
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Originally Posted by nist7
Premium. Yes.

We need some kind of FAQ/sticky thread in most of these sections....seems like same questions being asked every 1-2 weeks....
OR ... people could just perform a simple forum search. But there's a better chance that my girlfriend will want sex as often as I; ain't gonna happen.
Old Oct 19, 2016 | 12:57 PM
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Originally Posted by UlsterBoy13

HOWEVER people see the headline and think oh ok i should stop using premium, but reading the report CLEARLY states that this is only for drivers using premium in a car where the recommended fuel is Regular......
So you're telling me that most people are selective readers and really don't know jack shit about cars but think they do?!?!


Old Oct 19, 2016 | 05:09 PM
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Originally Posted by UlsterBoy13
its not rocket science, more like chemical engineering. but manufacturers recommend certain fuel grades for a reason.

the issue i see is when reports like the one AAA put out in September this year stating:AAA Finds Millions Of Drivers Waste Money On Premium Gas

AAA: Premium Gasoline Is A Waste Of Money For Many Drivers : NPR

HOWEVER people see the headline and think oh ok i should stop using premium, but reading the report CLEARLY states that this is only for drivers using premium in a car where the recommended fuel is Regular.....

For your TL - Stick to top tier premium and you will be fine. Other cars not required to run premium....use top tier and you will be fine.

You've just reminded me what put that thought in the back of my mind.

I did read that article and watch the video carefully.

You are correct - the majority of the instances were of people in cars that did not recommend premium originally but they thought it would give them better mileage/performance.

But the article/video was confusing as far as extending those findings to cars that recommended premium.
There seemed to be some hedging and/or confusing language, hence my question.

As far as a Sticky, yes, that's a good idea.

(Or doing a search first, which I did not do).
Old Oct 20, 2016 | 02:51 PM
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Mine pings does not matter I use 91 or 94. With 94 it reduces a bit but I don't like the 94 due to its ethanol content. I go with Shell 91 no ethanol but pings.
Old Oct 21, 2016 | 10:21 AM
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Originally Posted by the_razor
Mine pings does not matter I use 91 or 94. With 94 it reduces a bit but I don't like the 94 due to its ethanol content. I go with Shell 91 no ethanol but pings.
I also had random pinging issues when using ethanol free gasoline purchased from different stations in different cities, so I stopped using it.
Old Oct 25, 2016 | 11:31 AM
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There's *maybe* a $5 difference between filling a tank with Premium vs Regular.

Just used Gas Buddy, at Costco it's $1.90 for regular and $2.21 for premium. I typically average ~16 gallons when I fill it up from empty. That's $4.96 per tank.

If $5 is really breaking your bank once or twice a week maybe you shouldn't have purchased a $41k vehicle that has Premium fuel as the recommendation...
Old Oct 25, 2016 | 12:49 PM
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Originally Posted by TheMuffinMan
There's *maybe* a $5 difference between filling a tank with Premium vs Regular.

Just used Gas Buddy, at Costco it's $1.90 for regular and $2.21 for premium. I typically average ~16 gallons when I fill it up from empty. That's $4.96 per tank.

If $5 is really breaking your bank once or twice a week maybe you shouldn't have purchased a $41k vehicle that has Premium fuel as the recommendation...
Also that $5 difference won't take ya far as regular gas gets much worse gas mileage on our cars. You'll certainly be hard pressed to break even, and more-so when you factor in the engine and catalyst damage.
Old Oct 25, 2016 | 03:11 PM
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Premium always, I never even consider the lower grades..
Old Oct 26, 2016 | 04:28 PM
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Originally Posted by TheMuffinMan
There's *maybe* a $5 difference between filling a tank with Premium vs Regular.
Without weighing in on the regular versus premium debate, I just wanted to say that I saw the largest price differential that I can remember this past week. My wife and I were driving up I-95 in Virginia and we stopped at a Shell station. The prices were $2.05 for regular, $2.70 for mid-grade, and $3.05 for premium! Usually the step between each level is about 20 cents or maybe 30 cents, but here mid-grade was 65 cents more than regular, and premium was another 35 cents above that. My conclusion was that they set the price for regular somewhat low, so that they could advertise that low price on their big sign (with no indication of the mid-grade and premium prices). Many people (like me) are too lazy to get back in the car and drive to the next exit if they don't like the price of mid-grade or premium.

Gregg
Old Oct 26, 2016 | 05:39 PM
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Shell especially can be expensive because, AFAIK, all their premium grade gasoline is their new V-Power Nitro+ fuel...which is supposedly the best mass marketed gas you can buy from a public pump (I do remember all the CorvetteForum guys swear by the V-Power Nitro+). This may be a reason for the extraordinary higher cost.

Not sure if Shell sells premium that is non-V-power.....
Old Oct 26, 2016 | 07:16 PM
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I've been to lots of Shell stations and bought their premium for our TL (and mid-grade for our RDX), but I've never seen a price differential this big. As I said, at the stations I visit, it's usually about 20 cents or maybe 30 cents between grades. I think the most I've seen previously is about 40 cents. But this time it was 65 cents between regular and mid-grade. The stations along the interstate (and elsewhere) often only advertise their prices for regular and diesel. Unlike the old days, it seems rare to find a station that also advertises their mid-grade and premium prices on the big sign out front. I certainly could be wrong, but I think it's a marketing gimmick that draws people in with a price for regular that is "lower than normal" and then makes up for those smaller profits by charging prices for mid-grade and premium that are "higher than normal" (sort of like loss-leaders that other stores use to get you in the door). It's probably tougher to do that at local gas stations around town because people will just start going to other stations. But along the interstate, there is probably less repeat business with the same customer, so perhaps it's easier to use this trick.

Gregg
Old Oct 26, 2016 | 09:20 PM
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Originally Posted by vbgregg
I've been to lots of Shell stations and bought their premium for our TL (and mid-grade for our RDX), but I've never seen a price differential this big. As I said, at the stations I visit, it's usually about 20 cents or maybe 30 cents between grades. I think the most I've seen previously is about 40 cents. But this time it was 65 cents between regular and mid-grade. The stations along the interstate (and elsewhere) often only advertise their prices for regular and diesel. Unlike the old days, it seems rare to find a station that also advertises their mid-grade and premium prices on the big sign out front. I certainly could be wrong, but I think it's a marketing gimmick that draws people in with a price for regular that is "lower than normal" and then makes up for those smaller profits by charging prices for mid-grade and premium that are "higher than normal" (sort of like loss-leaders that other stores use to get you in the door). It's probably tougher to do that at local gas stations around town because people will just start going to other stations. But along the interstate, there is probably less repeat business with the same customer, so perhaps it's easier to use this trick.

Gregg
the perfect solution for me has been the "gasbuddy" app! It's pretty great at finding you cheap gas. 95% of the time the gas station I visit has the price posted on it.
Old Oct 27, 2016 | 10:24 AM
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I might be the only one who will honestly say that I use regular gas in my TL. It is your choice and depending on your driving style and priorities you might not need premium either. Over the course of 5-6 years of ownership the difference will add up. I do not drive my car like I stole it. I'd say it has hardly ever revved over 3,500 RPM. I like the nice ride, comfort, size, audio, etc of the TL. If a 4 banger were available I would have gotten one.
If you are the type of driver who normally pulls wide open throttle runs to engine redline you should probably run premium fuel. All those claims of better performance or max "peak performance" happen above 5,000 RPM. I don't drive like that.
I had a Lexus LS430 prior to my TL. ran 5,123 gallons of regular gas through it over 6 years. At a (current) cost difference of 60 cents between reg and prem I saved $3,074. This gives me more satisfaction than arriving at the next red light before all the other cars. I ran an experiment with my Lexus for 3 tank fill-ups where I put premium in it. MPG was no different. Went back to regular.
Since everybody's driving style is different, you should try it yourself. Fill up on regular a few tanks, not just once, and check your MPG and "feel". Then fill up with premium and drive the same stretches, in the same traffic, at the same time of day and see if you can tell a difference - I'd bet not.
Old Oct 27, 2016 | 11:35 AM
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Originally Posted by csmeance
the perfect solution for me has been the "gasbuddy" app! It's pretty great at finding you cheap gas. 95% of the time the gas station I visit has the price posted on it.
Would certainly have agreed with you a couple of months back, but since the app update, it's turned to $hi7. Not only is the interface worse, somehow it actually performs worse as well.

But I will say that it's handy (was even more so, before update) for highway travel, where the decision to fill up at this town or the next can have a bigger difference.
Old Oct 27, 2016 | 11:38 AM
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Originally Posted by vbgregg
Without weighing in on the regular versus premium debate, I just wanted to say that I saw the largest price differential that I can remember this past week. My wife and I were driving up I-95 in Virginia and we stopped at a Shell station. The prices were $2.05 for regular, $2.70 for mid-grade, and $3.05 for premium! Usually the step between each level is about 20 cents or maybe 30 cents, but here mid-grade was 65 cents more than regular, and premium was another 35 cents above that. My conclusion was that they set the price for regular somewhat low, so that they could advertise that low price on their big sign (with no indication of the mid-grade and premium prices). Many people (like me) are too lazy to get back in the car and drive to the next exit if they don't like the price of mid-grade or premium.

Gregg
Right on 95 outside of like DC Metro area? Because that wouldn't surprise me at all.
Old Oct 27, 2016 | 11:41 AM
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Originally Posted by ChunkyDA
I might be the only one who will honestly say that I use regular gas in my TL. It is your choice and depending on your driving style and priorities you might not need premium either. Over the course of 5-6 years of ownership the difference will add up. I do not drive my car like I stole it. I'd say it has hardly ever revved over 3,500 RPM. I like the nice ride, comfort, size, audio, etc of the TL. If a 4 banger were available I would have gotten one.
If you are the type of driver who normally pulls wide open throttle runs to engine redline you should probably run premium fuel. All those claims of better performance or max "peak performance" happen above 5,000 RPM. I don't drive like that.
I had a Lexus LS430 prior to my TL. ran 5,123 gallons of regular gas through it over 6 years. At a (current) cost difference of 60 cents between reg and prem I saved $3,074. This gives me more satisfaction than arriving at the next red light before all the other cars. I ran an experiment with my Lexus for 3 tank fill-ups where I put premium in it. MPG was no different. Went back to regular.
Since everybody's driving style is different, you should try it yourself. Fill up on regular a few tanks, not just once, and check your MPG and "feel". Then fill up with premium and drive the same stretches, in the same traffic, at the same time of day and see if you can tell a difference - I'd bet not.
I don't know if 3 tank fulls really gets you a good number. My MPG can vary wildly depending on usage. I don't mash on the gas anywhere and have been tracing my fuel since day one.

95% of the time I use Shell 93 in both my cars (supercharged S2000 and the TL)

Why would you have not bought a loaded Accord if you wanted to be cheap?
Old Oct 27, 2016 | 01:04 PM
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Originally Posted by TheMuffinMan
Right on 95 outside of like DC Metro area? Because that wouldn't surprise me at all.
It was in Colonial Heights, near the I-95 and I-85 split.
Old Oct 27, 2016 | 07:38 PM
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Originally Posted by Reorge
I also had random pinging issues when using ethanol free gasoline purchased from different stations in different cities, so I stopped using it.
I wish there were more ethanol free stations around where I live. That stuff is awful for my outdoor tools.
Old Oct 27, 2016 | 08:36 PM
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Originally Posted by csmeance
the perfect solution for me has been the "gasbuddy" app! It's pretty great at finding you cheap gas. 95% of the time the gas station I visit has the price posted on it.
Originally Posted by sockpuppet
Would certainly have agreed with you a couple of months back, but since the app update, it's turned to $hi7. Not only is the interface worse, somehow it actually performs worse as well.

But I will say that it's handy (was even more so, before update) for highway travel, where the decision to fill up at this town or the next can have a bigger difference.
Another app to consider is AroundMe. It is a handy travel app to find all sorts of things nearby (Restaurants, Banks, Theaters, Gas Stations - including the price of gas). You might give that one a try.
Old Oct 28, 2016 | 01:20 PM
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Originally Posted by RenoTL
Another app to consider is AroundMe. It is a handy travel app to find all sorts of things nearby (Restaurants, Banks, Theaters, Gas Stations - including the price of gas). You might give that one a try.
Not to discount AroundMe (I've never tried it), and without making it a competition, one of the real benefits to GasBuddy (especially since the upgrade which ruined the app), is the price increase alert. A few times I've gotten notice that gas was soon going up by 12 cents a liter or so (45 cents a liter), and it's almost always been right.

Of course, this has little to do with the original thread topic, and i apologize for the hijack.
Old Nov 4, 2016 | 01:18 PM
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My car is a 2010 fwd 3.5L with 110,000 km. Had it four years.
We most often use 89 octane fuel but also use 91 and 93 octane.
I cannot tell any performance difference and there is no engine pinging.
I know what pinging is, have experienced it many times in older cars from the '70s.
The engine (tach) in my car has never been near its redline and never will be.
Here in Ontario, premium fuel is about 1.32 Cdn per litre = about $3.84 U.S. per U.S. gallon.
One U.S. gal = 3.78 L

Last edited by jim_c; Nov 4, 2016 at 01:21 PM.
Old Nov 4, 2016 | 01:31 PM
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When I bought my 09 FWD the dealer gave me a free tank of gas.. It had to have been regular because I've noticed It ran a lot better after the first couple of fill ups of 93. I haven't seen any 91 around here yet, always seems to be 89 or 93. I'm good with the small price difference and going with the recommended fuel.
Old Nov 6, 2016 | 12:52 AM
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Hey I just a total subjective result on a fuel up. My wife just took my car out of town and she called left a message. She told me the TL really felt responsive and pulled 32MPG on a 150 mile trip.. Like I said it was subjective, however she never notices anything from new brakes to new supercharger. It funny I just put a full tank of full strength non-oxy gas. Ethanol-free gas stations in the U.S. and Canada
Seriously she never notices anything like different in the ride in snow tires. Dave's Roseville Auto Ha!

Last edited by Anicra; Nov 6, 2016 at 12:55 AM.
Old Nov 6, 2016 | 01:32 AM
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Octane vs Ingition Timing Plot

In my area, there is a $0.70 delta between 87 and 91 octane. I drive hundreds of miles a day for work, so that's over $1.1K in fuel costs per year. I was curious about how significant the impact would be where although it may be a different tune, this near identical 2015 3.5L engine is running 87 octane in the Honda Pilot. Here is a data plot captured from 2 acceleration runs per octane level. Yup! There is a significant timing difference. Also fair to note that the 89 octane data that I took was almost identical to the 91 octane runs. The car absolutley knows, and retards timing on 87 octane fule. On my 15 TLX Tech SHAWD, it also short shifts at 6,200 RPM ve 6,700 RPM when on the lower octane fuel. You can see the sharp drop in ignition timing as it temporarilly cuts power to grab the next gear! Enjoy the data!!
Attached Thumbnails Premium or regular gas?-igntiming87_91.jpg  
Old Nov 6, 2016 | 03:27 PM
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Cheapskate ?

I've often wondered about people who think nothing of dropping serious money for a fine car with a high performance engine, then piss and moan about having to use premium fuel. If fuel cost was going to be an issue for you, or you're that much of a cheapskate, then why did you buy the car? A corollary to which is if you can't afford the fuel, you can't afford the car. (or maybe don't deserve the car) - just my 2¢ worth
Old Nov 6, 2016 | 08:50 PM
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Originally Posted by cap'n preshoot
i've often wondered about people who think nothing of dropping serious money for a fine car with a high performance engine, then piss and moan about having to use premium fuel. If fuel cost was going to be an issue for you, or you're that much of a cheapskate, then why did you buy the car? A corollary to which is if you can't afford the fuel, you can't afford the car. (or maybe don't deserve the car) - just my 2¢ worth
This x100000000000000000000000000000000000

Old Nov 7, 2016 | 12:22 AM
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Originally Posted by Gremlin340
In my area, there is a $0.70 delta between 87 and 91 octane. I drive hundreds of miles a day for work, so that's over $1.1K in fuel costs per year. I was curious about how significant the impact would be where although it may be a different tune, this near identical 2015 3.5L engine is running 87 octane in the Honda Pilot. Here is a data plot captured from 2 acceleration runs per octane level. Yup! There is a significant timing difference. Also fair to note that the 89 octane data that I took was almost identical to the 91 octane runs. The car absolutley knows, and retards timing on 87 octane fule. On my 15 TLX Tech SHAWD, it also short shifts at 6,200 RPM ve 6,700 RPM when on the lower octane fuel. You can see the sharp drop in ignition timing as it temporarilly cuts power to grab the next gear! Enjoy the data!!
Sweet dataset man! Thanks for sharing!!!!
Old Nov 7, 2016 | 10:54 AM
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In the words of Gene Simmons, "if you have any extra dollar bills that you don't want, send them my way and I'll take good care of them". Nothing wrong with using actual data to make a $4.4K decision, which is what goes out the tailpipe over the life of the car on the Premium fuel cost delta. The Honda folks state "premium recommended" not required, so I decided to take an actual look. I do burn premium, to enjoy the full performance benefits of the car, but I now do so not because I read it on the internet, but because the data showed a difference.
Old Nov 7, 2016 | 01:47 PM
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Originally Posted by Cap'n Preshoot
A corollary to which is if you can't afford the fuel, you can't afford the car. (or maybe don't deserve the car) - just my 2¢ worth
Definitely

Originally Posted by Cap'n Preshoot
A corollary to which is if you can't afford the fuel, you can't afford the car. (or maybe don't deserve the car) - just my 2¢ worth
Um...no. Elitist, at best.
Old Nov 7, 2016 | 02:59 PM
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Originally Posted by Gremlin340
In my area, there is a $0.70 delta between 87 and 91 octane. I drive hundreds of miles a day for work, so that's over $1.1K in fuel costs per year. I was curious about how significant the impact would be where although it may be a different tune, this near identical 2015 3.5L engine is running 87 octane in the Honda Pilot. Here is a data plot captured from 2 acceleration runs per octane level. Yup! There is a significant timing difference. Also fair to note that the 89 octane data that I took was almost identical to the 91 octane runs. The car absolutley knows, and retards timing on 87 octane fule. On my 15 TLX Tech SHAWD, it also short shifts at 6,200 RPM ve 6,700 RPM when on the lower octane fuel. You can see the sharp drop in ignition timing as it temporarilly cuts power to grab the next gear! Enjoy the data!!
Interesting chart, of course the computer knows how to control the engine to reduce pre-ignition. This is not surprising at all. I would like to see a HP/torque curve plot using 87 and 91 octane fuel. My guess is that the performance benefit is at WOT on acceleration and the difference at part throttle acceleration and below 3,500 RPM is minimal.
I make my fuel choice based on driving style and simply suggest that other members might not need premium either.
BTW, I paid $16,000 for a used TL. There are not many other cars at that price point that are as nice and well built.
Old Nov 7, 2016 | 09:14 PM
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When I don't use premium, i use diesel, gives me more torque.
Old Nov 11, 2016 | 01:19 PM
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That's an interesting graph Gremlin; just curious how you generated that?
I'm not arguing for or against any particular practice regarding fuel usage, just trying to understand the facts.
Another question would be: what is the relationship between timing advance and potential "pinging" (pre-ignition) ?
Comments about who can "afford" or not afford anything are not relevant and not helpful.
Old Nov 12, 2016 | 07:11 PM
  #39  
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Originally Posted by ChunkyDA
Interesting chart, of course the computer knows how to control the engine to reduce pre-ignition. This is not surprising at all. I would like to see a HP/torque curve plot using 87 and 91 octane fuel. My guess is that the performance benefit is at WOT on acceleration and the difference at part throttle acceleration and below 3,500 RPM is minimal.
I make my fuel choice based on driving style and simply suggest that other members might not need premium either.
BTW, I paid $16,000 for a used TL. There are not many other cars at that price point that are as nice and well built.
Ping will happen regardless of what RPM you are at if you are using the wrong fuel. At higher RPM's, the additional heat from the engine provides a little bit more energy to start pre-ignition, but at the same time at higher rev's you risk a lot more damage than at lower rev's. Ping is Ping, and the car has to retard the timing to prevent damage. This means it's still spraying a little less fuel and reducing the amount of air substantially.

Originally Posted by jim_c
That's an interesting graph Gremlin; just curious how you generated that?
I'm not arguing for or against any particular practice regarding fuel usage, just trying to understand the facts.
Another question would be: what is the relationship between timing advance and potential "pinging" (pre-ignition) ?
Comments about who can "afford" or not afford anything are not relevant and not helpful.
The more you advance timing, the more air comes into the combustion chamber. More air means more fuel. With more of "everything" in the combustion chamber, it's more likely to pre-ignite from the compression on the piston upstroke rather than ignite at top dead center the proper time when the spark plug fires. Firing at the wrong time produces the knock since the piston still had to travel upwards, reach TDC, and then ignite to be forced down, but instead was ignited to early.

With that said, the J-series is very sensitive to Engine Coolant Temp (at the engine cylinder banks) and as well other factors that can cause the computer to retard timing besides fuel. The cold weather will eliminate a lot of these error inducing factors.
Old Nov 17, 2016 | 12:23 PM
  #40  
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I am curious why some 91 does not ping and then there is Shell 91 ping on initial load.



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