Gas. 87, 91, 93 Octane?

[MerlintheMad]

Since no one seems to agree im just gonna go with the middle ground. 91octane

That's not middle around here, that's the top octane.

 

[MisterMac]

93. The car is more efficient and operates the way it was designed. 91 octane is not typical in my area in case you are wondering.

Also the more money I pay for gas more than likely compensates for the long term damage and maintenance cause by running 87 in a direct injection turbo motor not designed for it when running nominally.

People must stop spreading lies by saying long-term damage will be caused by using lower octane than premium in these engines.

If Kia, the manufacturer, who warranties these powertrains for 100,000 miles, was the least but concerned about running 87 octane fuel in these engines, Premium octane would be "REQUIRED." It is that simple.

I've had my data reviewed while running 86 octane (elevation 4,500 ft above sea-level) and there is ZERO indication of improper detonation. The sensors more than adequately compensate the combustion process for any level of octane you run.

The key to the fuel you use in your Turbo Stinger is to use top-tier fuel which provides the means to keep your internals as clean as possible.

FUEL REQUIREMENTS

Your new vehicle is designed to use only unleaded fuel having a pump octane number ((R+M)/2) of 87 (Research Octane Number 91) or higher. (Do not use methanol blend- ed fuels.)

Your new vehicle is designed to obtain maximum performance with UNLEADED FUEL, as well as mini- mize exhaust emissions and spark plug fouling.

Never add any fuel system cleaning agents to the fuel tank other than what has been specified. (Consult an authorized Kia dealer for details.)

 

[NismoDPB]

People must stop spreading lies by saying long-term damage will be caused by using lower octane than premium in these engines.

If Kia, the manufacturer, who warranties these powertrains for 100,000 miles, was the least but concerned about running 87 octane fuel in these engines, Premium octane would be "REQUIRED." It is that simple.

I've had my data reviewed while running 86 octane (elevation 4,500 ft above sea-level) and there is ZERO indication of improper detonation. The sensors more than adequately compensate the combustion process for any level of octane you run.

The key to the fuel you use in your Turbo Stinger is to use top-tier fuel which provides the means to keep your internals as clean as possible.

FUEL REQUIREMENTS

Your new vehicle is designed to use only unleaded fuel having a pump octane number ((R+M)/2) of 87 (Research Octane Number 91) or higher. (Do not use methanol blend- ed fuels.)

Your new vehicle is designed to obtain maximum performance with UNLEADED FUEL, as well as mini- mize exhaust emissions and spark plug fouling.

Never add any fuel system cleaning agents to the fuel tank other than what has been specified. (Consult an authorized Kia dealer for details.)

People need to stop spreading lies and saying emphatically that using lower octane fuel causes no damage, because as far as I can tell, that has not been proven any more than using lower octane fuel will cause damage.

Here are the reasons I make the claims of efficiency and maintenance.

Here is what we do know
1) Using a lower octane fuel in a car that is tuned for higher octane will reduce fuel efficiency. This is a product of the ECU compensating for the lower octane fuel. This is not up for debate, it is a fact and cannot be countered by how people "feel" the fuel efficiency is when putting lower octane in. In most cases you are not actually saving money by using a lower octane fuel because of the loss of efficiency, but this of course depends on the difference in price between regular and premium at the time. On the flip side of the coin however the savings captured cannot be simply reduced to the difference in fuel prices.

2) Direct Injection motors are already prone to pre-ignition problems after they get miles on them. Using a lower octane fuel simply increases the chances of pre-ignition. Again this is just a simple fact about fuel properties and ICE engines.

3) Related to 2, running lower octane fuels will increase the emissions in the exhaust gas. Not only is it more polluting (which I'm sure no one cares about that much), you are putting additional tax into your emission control systems, so you may end up replacing those sooner. Many of those coming full circle and affecting the engine. Systems such as the EGR and PCV systems will recirc this higher emissions exhaust/blow buy back into the intake causing an increase of carbon deposits. See point 2 to understand why this is not a good thing. At best you will be increasing the maintenance cycle of scrubbing off your intake valves and other deposit removals in the engine, worst case.....let your imagination run away with you.

4) Until engine knock protection systems and the ECU begin predicting human behaviour, the system is and will always be re-active. Just because the system is there the ECU cannot eliminate knock 100%, you are merely decreasing the chance it's going to happen. Sure if you are cruising steady state on the highway the ECU is likely going to be able to protect against any knock. Its the extreme changes that become an issue. And by extreme, I mean a harder than normal acceleration. The system cannot predict this is going to happen, it can only react, so events such as simply accelerating increase the chance of knock.

None of those 4 points are opinions, these are factual based on modern ICE operation.

So can I say with 100% certainty that running a lower octane than the engine is tuned for will 100% of the time cause damage to your engine? No nothing in statistics is 100%. Can I say that you are increasing risk of damage by not following the manufacturer recommendations? Yes I am pretty sure given what we know that is likely the case.

Im not here to tell you how to live your life nor am I here to mock you for doing what you want with your car. But I do not think my opinion deserves to be mocked simply because people "feel" that running lower octane in cars not designed for it does nothing but save you money.

 

[MisterMac]

People need to stop spreading lies and saying emphatically that using lower octane fuel causes no damage, because as far as I can tell, that has not been proven any more than using lower octane fuel will cause damage.

Here are the reasons I make the claims of efficiency and maintenance.

Here is what we do know
1) Using a lower octane fuel in a car that is tuned for higher octane will reduce fuel efficiency. This is a product of the ECU compensating for the lower octane fuel. This is not up for debate, it is a fact and cannot be countered by how people "feel" the fuel efficiency is when putting lower octane in. In most cases you are not actually saving money by using a lower octane fuel because of the loss of efficiency, but this of course depends on the difference in price between regular and premium at the time. On the flip side of the coin however the savings captured cannot be simply reduced to the difference in fuel prices.

2) Direct Injection motors are already prone to pre-ignition problems after they get miles on them. Using a lower octane fuel simply increases the chances of pre-ignition. Again this is just a simple fact about fuel properties and ICE engines.

3) Related to 2, running lower octane fuels will increase the emissions in the exhaust gas. Not only is it more polluting (which I'm sure no one cares about that much), you are putting additional tax into your emission control systems, so you may end up replacing those sooner. Many of those coming full circle and affecting the engine. Systems such as the EGR and PCV systems will recirc this higher emissions exhaust/blow buy back into the intake causing an increase of carbon deposits. See point 2 to understand why this is not a good thing. At best you will be increasing the maintenance cycle of scrubbing off your intake valves and other deposit removals in the engine, worst case.....let your imagination run away with you.

4) Until engine knock protection systems and the ECU begin predicting human behaviour, the system is and will always be re-active. Just because the system is there the ECU cannot eliminate knock 100%, you are merely decreasing the chance it's going to happen. Sure if you are cruising steady state on the highway the ECU is likely going to be able to protect against any knock. Its the extreme changes that become an issue. And by extreme, I mean a harder than normal acceleration. The system cannot predict this is going to happen, it can only react, so events such as simply accelerating increase the chance of knock.

None of those 4 points are opinions, these are factual based on modern ICE operation.

So can I say with 100% certainty that running a lower octane than the engine is tuned for will 100% of the time cause damage to your engine? No nothing in statistics is 100%. Can I say that you are increasing risk of damage by not following the manufacturer recommendations? Yes I am pretty sure given what we know that is likely the case.

Im not here to tell you how to live your life nor am I here to mock you for doing what you want with your car. But I do not think my opinion deserves to be mocked simply because people "feel" that running lower octane in cars not designed for it does nothing but save you money.

Yes, follow manufacturer:

Your new vehicle is designed to use only unleaded fuel having a pump octane number ((R+M)/2) of 87 (Research Octane Number 91) or higher. (Do not use methanol blend- ed fuels.)

 

[Rob M]

Anyone remember what happened to Harry Potter when he suggested putting regular fuel in the Weasley's car?

 

[Rob M]

In all serious though.... Most of this discussion would not even exist if not for SHALE OIL!!!

Just as car manufacturers are switching to smaller turbocharged/supercharged engines that can benefit from higher octane fuels (both for performance and reduced emissions), the US determines that energy independence is paramount and goes all in on the shale oil boom. Only problem is - shale oil is very light so you end up distilling gasoline with lower octane. Refiners then have to add much greater quantities of expensive octane boosters (alkylates, etc.) to yield premium fuel. Therein lies the dilemma. If you live in a state where most of the fuel is refined from shale oil you are currently paying $0.60/gal (~25%) more for premium and around $0.40 more for midgrade. Otherwise, the difference in price is only around $0.30/gal (e.g., CA) between premium and regular. As long as the huge shale-derived gasoline price disparity exists, and it is not a requirement to use higher grades of fuel, people will feel less compelled to do so.

I've been using 87 most of the time. On occasion, if I foresee more spirited driving opportunities I might run a tank of 93 from my local Gulf (not tier 1) station since the price disparity is smaller. Can always just run a bottle of techron through the tank every oil change interval as per Kia.

 

[NismoDPB]

Yes, follow manufacturer:

Your new vehicle is designed to use only unleaded fuel having a pump octane number ((R+M)/2) of 87 (Research Octane Number 91) or higher. (Do not use methanol blend- ed fuels.)

That's great for whatever car that is for. But here are the requirements for the stinger. Albeit it looks like a sticker was placed over the text that was there. perhaps you do not have the correction sticker.

 

[kit385]

I usually fill up 87 on daily drive I don't have a heavy foot. but if I want to go for a spin on the mountains I usually fill up with v power 91. And yes, 91 have better response and power. I also noticed 91 have slighty better gas mileage over 87, But not very big of a difference so filling 87 is still save me some buck. if I fill 87 I will be on comfort mode all the time for my daily and 91 on eco mode+sport mode while I daily and spin.

 

[MisterMac]

That's great for whatever car that is for. But here are the requirements for the stinger. Albeit it looks like a sticker was placed over the text that was there. perhaps you do not have the correction sticker.
View attachment 20511

I don't need the "correction" sticker. There is a huge difference between recommended and required plus another huge difference between could and will when it comes to maximum performance.

 

[RUFFSTUFF]

In my life I'm fairly certain that no 2 tanks of gas have been driven the same.

 

[NismoDPB]

You act like you are not the one who's put the cornerstone of your argument on this little excerpt

Your new vehicle is designed to use only unleaded fuel having a pump octane number ((R+M)/2) of 87 (Research Octane Number 91) or higher. (Do not use methanol blend- ed fuels.)

Im sorry it appears to be from the incorrect vehicle, but this is what you wanted to use to argue with. Not for nothing, the heading on this section says "fuel requirements"

I don't need the "correction" sticker. There is a huge difference between recommended and required plus another huge difference between could and will when it comes to maximum performance.

Yet you are conveniently leaving out the part where the manufacturer clearly states what could happen if you do not use their recommended octane fuel. You know that whole tidbit of power loss and efficiency loss.

This is all a great deal of misdirection though because the only reason you were arguing with me in the first place is to tell me that running a lower octane can be done with no adverse effects, and using the owner's manual to back you up.

Like you said "Yes, follow manufacturer"

 

[MisterMac]

You act like you are not the one who's put the cornerstone of your argument on this little excerpt



Im sorry it appears to be from the incorrect vehicle, but this is what you wanted to use to argue with. Not for nothing, the heading on this section says "fuel requirements"



Yet you are conveniently leaving out the part where the manufacturer clearly states what could happen if you do not use their recommended octane fuel. You know that whole tidbit of power loss and efficiency loss.

This is all a great deal of misdirection though because the only reason you were arguing with me in the first place is to tell me that running a lower octane can be done with no adverse effects, and using the owner's manual to back you up.

Like you said "Yes, follow manufacturer"

Oh, this has nothing to do with you. This is for those who buy into the hype and come to believe they will ruin their cars if they don't spend an extra wad of cash at the filling station. So they can be fully informed, make their own decision, and sleep well knowing they are fine.

 

[Rob M]

Professor Umbridge,

MisterMac's quote is identical to the Fuel Requirements specified in my 2018 Stinger (GT2) owner's manual. "Your new vehicle is designed to use only unleaded fuel having a pump octane number ((R+M)/2) of 87 (Research Octane Number 91) or higher. (Do not use methanol blend- ed fuels.)"

Yes, Kia clearly states in the stickered version that you MAY experience a loss in power and fuel economy, but they don't quantify it. Under normal driving conditions these differences are so small so as be negligible. You WILL NOT have any adverse affects wrt engine reliability by using regular unleaded fuel.

 

[NismoDPB]

Professor Umbridge,

MisterMac's quote is identical to the Fuel Requirements specified in my 2018 Stinger (GT2) owner's manual. "Your new vehicle is designed to use only unleaded fuel having a pump octane number ((R+M)/2) of 87 (Research Octane Number 91) or higher. (Do not use methanol blend- ed fuels.)"

Yes, Kia clearly states in the stickered version that you MAY experience a loss in power and fuel economy, but they don't quantify it. Under normal driving conditions these differences are so small so as be negligible. You WILL NOT have any adverse affects wrt engine reliability by using regular unleaded fuel.

The Picture I attached is from my stinger owner's manual. I gave the benefit of the doubt that the manual being referenced was not updated.

 

[NismoDPB]

This is for those who buy into the hype and come to believe they will ruin their cars if they don't spend an extra wad of cash at the filling station. So they can be fully informed, make their own decision, and sleep well knowing they are fine.

Well we have come full circle then because I have yet to see how you have "informed" anyone about how they will be "fine" other than presenting personal anecdote and the fact you just feel it's going to be okay.

 

[MisterMac]

Well we have come full circle then because I have yet to see how you have "informed" anyone about how they will be "fine" other than presenting personal anecdote and the fact you just feel it's going to be okay.

Ditto.

 

[NismoDPB]

Ditto.

I can help. See post #303

Feel free to refute the non anecdotal claims in that post.

 

[MisterMac]

People need to stop spreading lies and saying emphatically that using lower octane fuel causes no damage, because as far as I can tell, that has not been proven any more than using lower octane fuel will cause damage.

Here are the reasons I make the claims of efficiency and maintenance.

Here is what we do know
1) Using a lower octane fuel in a car that is tuned for higher octane will reduce fuel efficiency. This is a product of the ECU compensating for the lower octane fuel. This is not up for debate, it is a fact and cannot be countered by how people "feel" the fuel efficiency is when putting lower octane in. In most cases you are not actually saving money by using a lower octane fuel because of the loss of efficiency, but this of course depends on the difference in price between regular and premium at the time. On the flip side of the coin however the savings captured cannot be simply reduced to the difference in fuel prices. You are assuming the Stinger is tuned for an exact octane level at 91+ when in fact is is factory tuned for a minimum octane level or higher.

2) Direct Injection motors are already prone to pre-ignition problems after they get miles on them. Using a lower octane fuel simply increases the chances of pre-ignition. Again this is just a simple fact about fuel properties and ICE engines. You are assuming all Direct Injection programming is the same. Again, my own data shows no pre-ignition, at least proving your assumption is incorrect on one vehicle out of the bunch...

3) Related to 2, running lower octane fuels will increase the emissions in the exhaust gas. Not only is it more polluting (which I'm sure no one cares about that much), you are putting additional tax into your emission control systems, so you may end up replacing those sooner. Many of those coming full circle and affecting the engine. Systems such as the EGR and PCV systems will recirc this higher emissions exhaust/blow buy back into the intake causing an increase of carbon deposits. See point 2 to understand why this is not a good thing. At best you will be increasing the maintenance cycle of scrubbing off your intake valves and other deposit removals in the engine, worst case.....let your imagination run away with you. Fine. Yet, at $6.00 per tank price difference between 87 and 91 octane here in El Paso Texas, a driver could save $2,000.00 over 100,000 miles in fuels cost alone. That pays for a lot of parts "IF" they wear out in that time.

4) Until engine knock protection systems and the ECU begin predicting human behaviour, the system is and will always be re-active. Just because the system is there the ECU cannot eliminate knock 100%, you are merely decreasing the chance it's going to happen. Sure if you are cruising steady state on the highway the ECU is likely going to be able to protect against any knock. Its the extreme changes that become an issue. And by extreme, I mean a harder than normal acceleration. The system cannot predict this is going to happen, it can only react, so events such as simply accelerating increase the chance of knock. These computers adapt quicker than you or I can think and remain at that programming for lower octane until such time as enough demand (hard acceleration) is placed upon it to change and realize there is more potential within the fuel. Most people never get on the accelerator that way and will have zero issues. We aren't racing these cars on the track day in and day out....

None of those 4 points are opinions, these are factual based on modern ICE operation.

So can I say with 100% certainty that running a lower octane than the engine is tuned for will 100% of the time cause damage to your engine? No nothing in statistics is 100%. Can I say that you are increasing risk of damage by not following the manufacturer recommendations? Yes I am pretty sure given what we know that is likely the case.

Im not here to tell you how to live your life nor am I here to mock you for doing what you want with your car. But I do not think my opinion deserves to be mocked simply because people "feel" that running lower octane in cars not designed for it does nothing but save you money.

See my rebuttals in bold above. You will have to click expand on the quoted text.

 

[NismoDPB]

See my rebuttals in bold above.

Ok you are just being ridiculous now. Have a nice day friend

 

[MisterMac]

Ok you are just being ridiculous now. Have a nice day friend

All the best to you