What's the best octane to use?

That’s incorrect and stop making up nonsense to try to justify why you aren’t following manufacturers recommendations.

As the current manual says anything less than premium fuel “could cause a loss of engine power and increased fuel consumption”. That means on premium it will perform as intended, but on 87/89 your causing the engine to protect itself from knock/detonation and it must pull timing to compensate. That in turn makes it less efficient so it loses power and fuel economy. That’s definitely under performing which is not how Kia built and intended the engine to run.

This has been stated and explained dozens of times in different threads.
Gas. 87, 91, 93 Octane?
That one example explains that when AAA thoroughly tested a wide variety of vehicles on required vs recommended fuels it found similar high performance engines gained 8-15% better fuel economy(2-4mpg) and about 10whp more just by using premium. Other car magazines have done similar testing and found some engines gained about 20whp/20wtq on 93.

You and the few people not using the recommended premium fuel crack me up. You chose to spend $5k-10k or $100/m more for the high performance 3.3TT but then use bottom of the barrel gas just to try to save a few bucks.:rolleyes: If you were concerned over .30-.50/g difference in fuel prices you should have gotten the less performance oriented 2.0l instead.

Jeez dude, every thread I click on I see you arguing with a different person. You really love arguing with everyone.
 
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Jeez dude, every thread I click on I see you arguing with a different person. You really love arguing with everyone.

When you're right, you're right.
 
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When you're right, you're right.

I'm not saying he's wrong or that there should be no disagreeing on the forum. It's just the overall demeanor of A LOT of his posts tend to be antagonistic, bickering, or combative.

There are more tactful ways to disagree with someone than what I typically see from him. That's all.
 
That’s incorrect and stop making up nonsense to try to justify why you aren’t following manufacturers recommendations.

As the current manual says anything less than premium fuel “could cause a loss of engine power and increased fuel consumption”. That means on premium it will perform as intended, but on 87/89 your causing the engine to protect itself from knock/detonation and it must pull timing to compensate. That in turn makes it less efficient so it loses power and fuel economy. That’s definitely under performing which is not how Kia built and intended the engine to run.

This has been stated and explained dozens of times in different threads.
Gas. 87, 91, 93 Octane?
That one example explains that when AAA thoroughly tested a wide variety of vehicles on required vs recommended fuels it found similar high performance engines gained 8-15% better fuel economy(2-4mpg) and about 10whp more just by using premium. Other car magazines have done similar testing and found some engines gained about 20whp/20wtq on 93.

You and the few people not using the recommended premium fuel crack me up. You chose to spend $5k-10k or $100/m more for the high performance 3.3TT but then use bottom of the barrel gas just to try to save a few bucks.:rolleyes: If you were concerned over .30-.50/g difference in fuel prices you should have gotten the less performance oriented 2.0l instead.

@StungBlueGT2 , you are the crack-up.

See above, the word is "could", not will. My experience is no noticeable loss of power and fuel economy does not change between 87 and 91. None, zero, zilch difference.

Your arguments to support your beliefs that you must use premium fuel are nothing more than supposition based on an illiterate interpretation. If the OM read this way: "Premium octane fuel is required. Use of non-premium fuel WILL cause the engine to lose power and to consume more fuel", your arguments would be indisputable. However, that is not the case.

Following in suit, your assumption that the reason behind running regular fuel is based on trying to save a few bucks demonstrates you are either biased or clueless. Now, I realize the Stinger GT2 could very well be the most expensive and highest performance car you could ever dream of having. It might be your "baby", and you can't even imagine not feeding your baby the highest dollar caviar available. That is fine, go buy the premium caviar. I'll take the regular caviar and enjoy it just as much.

Now, @StungBlueGT2 , do yourself and everyone else on this forum a public service: get over yourself. Accept the fact that aside from a few horsepower difference at the height of the power band, the owner of a Stinger GT may run any grade of Top Tier fuel they desire for whatever reason. If, over the long-term, it is proven that those who chose to run regular instead of premium fuel caused some irreparable harm to their engine, I will be the first publish those results and to hail your lucky guess as accurate.
 
From interior to exterior to high performance - everything you need for your Stinger awaits you...
That’s incorrect and stop making up nonsense to try to justify why you aren’t following manufacturers recommendations.

As the current manual says anything less than premium fuel “could cause a loss of engine power and increased fuel consumption”. That means on premium it will perform as intended, but on 87/89 your causing the engine to protect itself from knock/detonation and it must pull timing to compensate. That in turn makes it less efficient so it loses power and fuel economy. That’s definitely under performing which is not how Kia built and intended the engine to run.

This has been stated and explained dozens of times in different threads.
Gas. 87, 91, 93 Octane?
That one example explains that when AAA thoroughly tested a wide variety of vehicles on required vs recommended fuels it found similar high performance engines gained 8-15% better fuel economy(2-4mpg) and about 10whp more just by using premium. Other car magazines have done similar testing and found some engines gained about 20whp/20wtq on 93.

You and the few people not using the recommended premium fuel crack me up. You chose to spend $5k-10k or $100/m more for the high performance 3.3TT but then use bottom of the barrel gas just to try to save a few bucks.:rolleyes: If you were concerned over .30-.50/g difference in fuel prices you should have gotten the less performance oriented 2.0l instead.
Hey Mr. Stung Blue. Would you put your Stinger title on the line in multiple BLIND octane tests that your stinger is burning less than 91 octane as the manual states? If less than 91 is not damaging the engine, which KIA does NOT say it does, isn't it a good thing to have the option to burn regular through premium grade if you choose? As a new Stinger owner would you please forward some written proof on the facts you are claiming?
 
@StungBlueGT2 , you are the crack-up.

See above, the word is "could", not will. My experience is no noticeable loss of power and fuel economy does not change between 87 and 91. None, zero, zilch difference.

Your arguments to support your beliefs that you must use premium fuel are nothing more than supposition based on an illiterate interpretation. If the OM read this way: "Premium octane fuel is required. Use of non-premium fuel WILL cause the engine to lose power and to consume more fuel", your arguments would be indisputable. However, that is not the case.

Following in suit, your assumption that the reason behind running regular fuel is based on trying to save a few bucks demonstrates you are either biased or clueless. Now, I realize the Stinger GT2 could very well be the most expensive and highest performance car you could ever dream of having. It might be your "baby", and you can't even imagine not feeding your baby the highest dollar caviar available. That is fine, go buy the premium caviar. I'll take the regular caviar and enjoy it just as much.

Now, @StungBlueGT2 , do yourself and everyone else on this forum a public service: get over yourself. Accept the fact that aside from a few horsepower difference at the height of the power band, the owner of a Stinger GT may run any grade of Top Tier fuel they desire for whatever reason. If, over the long-term, it is proven that those who chose to run regular instead of premium fuel caused some irreparable harm to their engine, I will be the first publish those results and to hail your lucky guess as accurate.
I burnt my first tank of 91 that came with my new 2020 GT2. I'm now half way through a tank of 87 octane. I can't thus far see no blaring, outright or obvious performance difference. Even if I get 5 miles more per gal (which I hardly believe) on 91 vs 87 that's like a big 75 miles more per tank. Like...I don't consider that a big deal. Today here in Denver 87 is $2.35 gal premium is $3.15 per gal. Maybe on race day at the track or strip (ha,ha ha) I'll be a premium only user. For now I'll burn regular and throw in a tank of prem. every now and then to see if there is a difference.
 
I'm not saying he's wrong or that there should be no disagreeing on the forum. It's just the overall demeanor of A LOT of his posts tend to be antagonistic, bickering, or combative.

There are more tactful ways to disagree with someone than what I typically see from him. That's all.

Fair enough.
 
Most of the time I am either running E30-ish or Boostane, so I find this thread amusing...
 
Hey Mr. Stung Blue. Would you put your Stinger title on the line in multiple BLIND octane tests that your stinger is burning less than 91 octane as the manual states? If less than 91 is not damaging the engine, which KIA does NOT say it does, isn't it a good thing to have the option to burn regular through premium grade if you choose? As a new Stinger owner would you please forward some written proof on the facts you are claiming?

It's a fact of how an internal combustion engine works. If you run a lower octane in a car that nominally runs on higher octane, the ECU has to retard timing to avoid knock. When the car pulls timing it is less efficient and performance is reduced. It's not really an opinion.
As a new stinger owner you should note that your engine is a direct injection engine which is already prone to knock so take that for what it's worth.

It's your car do what you want. You can run 87 all day, just know it's not nominal operation.

Maybe you can find a tuner that would give you an 87 map if your heart is set on it.
 
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From interior to exterior to high performance - everything you need for your Stinger awaits you...
Hello turbo AWD. I mentioned the $.50 more per gallon. You live in No. Cal. (the bay area I presume) After checking on Gas Buddy you are correct regarding the smaller difference between gas grades. But...….people in California from the start are being gouged and swindled on their gas prices. Cali gas sellers are just burying the price difference in the grades from the start. I live In Denver.
San Fran reg. grade $3.40
Denver reg. grade 2.35

San Fran. mid grade $3.55
Denver mid grade 2.75

San Fran prem. grade 3.60
Denver prem. grade 3.15

It's not the gas sellers as such, it's mostly state requirements. CA requires oxygenated gas, and only a few refineries make it, so more $$. Plus, CA adds another $0.75/gallon (at least) in taxes over neighboring states like NV and AZ. In 2008, when gas prices hit ~$4/gallon around the country, we were $4.50-4.60/gallon, IIRC. I think we added another $0.10 last year or something.

Your numbers are more like Canada where I was paying like $0.50/gallon more for premium over regular. No wonder you're so set on using 87 - and obviously, you can understand why I use 91 100% of the time (plus some E85 :-) without ever thinking about it. I fill up maybe once a week and do 3-4 gallons E85, so ~10 gallons 91. That's $2 * 50 weeks/year = $100/year (roughly) more to run 91 vs 87. Total no-brainer.
 
It's a fact of how an internal combustion engine works. If you run a lower octane in a car that nominally runs on higher octane, the ECU has to retard timing to avoid knock. When the car pulls timing it is less efficient and performance is reduced. It's not really an opinion.
As a new stinger owner you should note that your engine is a direct injection engine which is already prone to knock so take that for what it's worth.

It's your car do what you want. You can run 87 all day, just know it's not nominal operation.

Maybe you can find a tuner that would give you an 87 map if your heart is set on it.
Thanks for your explanation. So long as my warranty is not in jeopardy I'll run 87. Should I want optimum performance I'll run premium. Again.….do you think you could pass multiple blind octane tests in everyday driving???
 
It's not the gas sellers as such, it's mostly state requirements. CA requires oxygenated gas, and only a few refineries make it, so more $$. Plus, CA adds another $0.75/gallon (at least) in taxes over neighboring states like NV and AZ. In 2008, when gas prices hit ~$4/gallon around the country, we were $4.50-4.60/gallon, IIRC. I think we added another $0.10 last year or something.

Your numbers are more like Canada where I was paying like $0.50/gallon more for premium over regular. No wonder you're so set on using 87 - and obviously, you can understand why I use 91 100% of the time (plus some E85 :) without ever thinking about it. I fill up maybe once a week and do 3-4 gallons E85, so ~10 gallons 91. That's $2 * 50 weeks/year = $100/year (roughly) more to run 91 vs 87. Total no-brainer.
Based on your gas prices I totally agree. It was like a breath of fresh air and a new lease on life when I moved from Cali. to Colorado.
 
Thanks for your explanation. So long as my warranty is not in jeopardy I'll run 87. Should I want optimum performance I'll run premium. Again.….do you think you could pass multiple blind octane tests in everyday driving???
Do you mean if I ran 87 in my car and no one told me could I tell the difference?
 
Maybe you can find a tuner that would give you an 87 map if your heart is set on it.

Yeah, all these 87 octane folks should just get a JB4 and run Map 4... Perfect for them.
 
From interior to exterior to high performance - everything you need for your Stinger awaits you...
Again.….do you think you could pass multiple blind octane tests in everyday driving???
Do you mean if I ran 87 in my car and no one told me could I tell the difference?
Not unless I was doing launches and engaging the kickdown switch. Even then, I'd wonder if the ECU were playing "games' with me, e.g. restricting power to the front and/or rear wheels for whatever complex of perceived conditions that "She" deems suitable to limit power. It happens. So, unless actual performance is tested enough to suspect that some unknown factor is messing up my peak performance, I would not suspect octane reduction as the first cause.

Average MPG? Over time the reduction would make me suspicious. But I doubt it'd be significant enough to flag my attention. It's obvious that many drivers don't see a noticeable difference in average MPG when using lower octane. But there are drivers who do claim that they get noticeably lower miles out of a tank of gas when they use regular. So, it would depend on my car, being one way or the other.

I've said this before (maybe on this thread, we have so many "gassy" threads:P): I use premium fuel because of the car I bought. I'm not interested in proving anything. I just want to know that my car is operating at full efficiency, and will perform when I demand it. If I drive an entire tank and never do a dig, and only do sedate city driving, I still know that if/when I demand WOT my car is going to give me peak torque right now. That pleases my aesthetics. I am buying satisfaction by putting in premium, Top Tier gasoline.
 
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It's happened in my MK5 GTI and I thought I had a vacuum leak. It was noticeably slower and idled rough.

Would I be able to tell in the stinger? Being that I'm very used to how it performs on premium fuel for over a year, I am 100% confident I would be able to tell the difference based on my previous experiences. Guess we will never know though.
 
Not unless I was doing launches and engaging the kickdown switch. Even then, I'd wonder if the ECU were playing "games' with me, e.g. restricting power to the front and/or rear wheels for whatever complex of perceived conditions that "She" deems suitable to limit power. It happens. So, unless actual performance is tested enough to suspect that some unknown factor is messing up my peak performance, I would not suspect octane reduction as the first cause.

Average MPG? Over time the reduction would make me suspicious. But I doubt it'd be significant enough to flag my attention. It's obvious that many drivers don't see a noticeable difference in average MPG when using lower octane. But there are drivers who do claim that they get noticeably lower miles out of a tank of gas when they use regular. So, it would depend on my car, being one way or the other.

I've said this before (maybe on this thread, we have so many "gassy" threads:p): I use premium fuel because of the car I bought. I'm not interested in proving anything. I just want to know that my car is operating at full efficiency, and will perform when I demand it. If I drive an entire tank and never do a dig, and only do sedate city driving, I still know that if/when I demand WOT my car is going to give me peak torque right now. That pleases my aesthetics. I am buying satisfaction by putting in premium, Top Tier gasoline.
Okay, okay, okay!!! Cool your jets. I'll say no more. I thank you as does Exon Mobil, ConocoPhillips, Shell, etc., etc., etc.
 
I use 91 "premium" in my NA Honda Wagon. Is it expensive here in CA? You bet. Do I hit 7k RPM all the time? You bet. That's why I use good gas, even more so with the stinger. You don't buy a expensive twin turbo car and put cheap trash gas in it. And then expect it to perform and last long...
 
I use 91 "premium" in my NA Honda Wagon. Is it expensive here in CA? You bet. Do I hit 7k RPM all the time? You bet. That's why I use good gas, even more so with the stinger. You don't buy a expensive twin turbo car and put cheap trash gas in it. And then expect it to perform and last long...
Well that's a different story altogether. If your Honda is tuned to run on 87 then putting premium in it is not going to give you any benefits. 87 octane isn't low quality gas, it doesnt burn any dirtier nor is it inherently less efficient. It is just a lower octane rating and It just becomes those things when you put it in a car that is tuned for a higher octane.
 
From interior to exterior to high performance - everything you need for your Stinger awaits you...
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