Starting to Ping!?!
#16
06-17-2005, 07:14 PM
Originally Posted by allforthecash
you got to be a fool to use 89 gas in this car..NO **** its gona run like crap!...i can tell the difference sometimes when i end up with a bad tank of gas from a junkie gas station....the car runs like CRAP... "oh should i use premium"...really? you think so? no way? 
On a side note, I would be interested in seeing track slips of the same car running the different grades, preferably at the same location, on the same night, at or around the same ambient temps. I would be very suprised to see more than a few percentage points difference in accel times and trap speeds.
#17
06-17-2005, 07:23 PM
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Originally Posted by trey's wife
Because it's like batteries, light bulbs and several other things in life - if the less expensive is no better than the expensive stuff then there is no way I am paying more for it. I'm cheap pure and simple. I like my money and I see no reason to spend the extra when it doesn't make a difference. Note my original reply that we have tried them all and have found what makes a difference in our car - so we will use it. Now I will also say that with no other vehicle I have owned has it made an ounce of difference. In those cases I think it is quite ridiculous to pay the extra for no extra benefit. Our family spends over $200 a month on gas with the cheap stuff and only one full time driver. That few dollars a tank adds up. IMHO - more money for no improvement = lack of thought BUT more money for notable improvement = reasonable.
#18
06-17-2005, 08:03 PM
#19
06-17-2005, 09:05 PM
Originally Posted by skeleton_cru
Wow, all this talk of 87/89 octane being OK and you found out first hand it wasn't (knocking/pinging). So why the the defensive stance?
My defensive stance is regarding the fact that I should have just done this without regard to if it were better or not just because it should have been obvious. I argue the point that 89 or 93 are not always the better gasoline. I have just this evening had a discussion regarding this very subject which has me on a mission to do some further "research". We are the horrible people who god forbid buy gas at Racetrac/Raceway rather than Chevron, BP or some of the others. It was argued to me that the 87 grade at BP may well be of relatively same quality as the 93 at Racetrac. My intent is to test this theory and if it is proven true then I will go back to the 87 just at a different place. I do not dispute that there are times when the gas makes a difference I just dispute the assumption that more expensive means better by default.
#20
06-17-2005, 09:09 PM
Originally Posted by Mr. G
For each ten thousand miles, about 500 gallons at 20 mpg.
Max 10 cents more per gallon for premium.
$50.
For most people, no more than $75-$100 per year.
That would be 0.3% of what I paid for the car and about what I spend on a nice dinner for two.
For me it would be worth it.
Max 10 cents more per gallon for premium.
$50.
For most people, no more than $75-$100 per year.
That would be 0.3% of what I paid for the car and about what I spend on a nice dinner for two.
For me it would be worth it.
Again, I respect the take on that - I'm just not sure that I agree on principal alone. If my car runs with no issues at 87 then I still doubt I would run 93.
#21
06-17-2005, 10:32 PM
Octane ratings at the pump are an average of two different methods of calculating octane, the MON and RON, based on running a test engine at two different speeds and determining the test octane mixture at which the engine begins to knock. The MON represents a more severe load. So a gasoline could be rated the same octane as another but be less protective at higher stress because it has a greater RON/MON ratio. So you have less leeway with lower octane rated gasoline.
Second, with modern knock sensors, when fuel with inadequate octane to prevent knocking is used, spark plug firing is retarded to prevent premature combustion in the chamber and knocking which could damage the engine. But this is not optimal, results in a richer fuel-air mix and may result in higher temperature in the combustion chamber, and lower efficiency. None of this may be obvious, especially if the driving conditions are not particularly demanding. So a lack of obvious knocking does not mean that the engine is operating optimally or that minimal but cumulative damage is not occurring. So, while it is true that using 93 octane gasoline in a Chevette is a waste of money, I believe it is a false economy to use less than 91 octane in a high compression, high performance car.
Second, with modern knock sensors, when fuel with inadequate octane to prevent knocking is used, spark plug firing is retarded to prevent premature combustion in the chamber and knocking which could damage the engine. But this is not optimal, results in a richer fuel-air mix and may result in higher temperature in the combustion chamber, and lower efficiency. None of this may be obvious, especially if the driving conditions are not particularly demanding. So a lack of obvious knocking does not mean that the engine is operating optimally or that minimal but cumulative damage is not occurring. So, while it is true that using 93 octane gasoline in a Chevette is a waste of money, I believe it is a false economy to use less than 91 octane in a high compression, high performance car.
#22
06-17-2005, 11:08 PM
Originally Posted by trey's wife
I respect that by all means. In our case it is right at 20 cents a gallon difference at the "generic" station we use now. (see my reply to Cru) If I were to go from 87 at our current station to the 93 at the local BP station it would be right at 40 cents a gallon difference. All the stations near us are 10 cents between the grades with the "generic" stations premium being the same or within 5 cents of the 87 at the "name brand" stations.
Again, I respect the take on that - I'm just not sure that I agree on principal alone. If my car runs with no issues at 87 then I still doubt I would run 93.
Again, I respect the take on that - I'm just not sure that I agree on principal alone. If my car runs with no issues at 87 then I still doubt I would run 93.
MrG, you mean someone still has a Chevette? (aka Shove Et, LOL!)
#23
06-17-2005, 11:11 PM
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That's just it, the car WILL have issues if you run with regular octane. The ping you're hearing is more than just annoying.
'If fuel octane is too low for a given compression ratio, the fuel prematurely and spontaneously ignites too early and the fuel charge EXPLODES rather than BURNS resulting in incomplete combustion. The net effect is a loss in power and possible engine damage. The operator hears an audible "knock" or "ping", referred to as detonation. Detonation may vary from a faint noise on light acceleration to a constant, deep hammering noise while driving at a constant speed. Improper timing adjustments, vacuum leaks, or excessively lean fuel mixtures may also cause detonation."
Listen, I'm nearly 40 years old and don't care what octane level you choose to put in your car. My honest, objective opinion is that if the price of premium fuel is dictating whether or not you should use the CORRECT octane in your high compression sports car, you should consider trading in your vehicle. I'm not saying that to sound confrontational, but using the lower octane in a VQ engine is wrong. Period. I don't need to ask Infiniti for clarification either. Call some independent mechanics and run it by them. Tell them you own a Nissan 350Z (they'll be more familiar with it), you use regular octane gas, and get a lot of knocking and pinging. Then ask them if it's bad. Nuff' said.
'If fuel octane is too low for a given compression ratio, the fuel prematurely and spontaneously ignites too early and the fuel charge EXPLODES rather than BURNS resulting in incomplete combustion. The net effect is a loss in power and possible engine damage. The operator hears an audible "knock" or "ping", referred to as detonation. Detonation may vary from a faint noise on light acceleration to a constant, deep hammering noise while driving at a constant speed. Improper timing adjustments, vacuum leaks, or excessively lean fuel mixtures may also cause detonation."
Listen, I'm nearly 40 years old and don't care what octane level you choose to put in your car. My honest, objective opinion is that if the price of premium fuel is dictating whether or not you should use the CORRECT octane in your high compression sports car, you should consider trading in your vehicle. I'm not saying that to sound confrontational, but using the lower octane in a VQ engine is wrong. Period. I don't need to ask Infiniti for clarification either. Call some independent mechanics and run it by them. Tell them you own a Nissan 350Z (they'll be more familiar with it), you use regular octane gas, and get a lot of knocking and pinging. Then ask them if it's bad. Nuff' said.
Last edited by BobbyG123; 06-17-2005 at 11:15 PM.
#24
06-17-2005, 11:35 PM
Originally Posted by OCG35
As always, the higher the octane the better… My question is: If you own one of the highest rated performance sedans (in many cases THE highest rated), why would you put sh!tty fuel in it?
It's not "As Always, the higher the octane the better"
I would put whatever the users manual suggests. If you are getting knock while still using what the manual suggests then either the Manufacturer needs to fix their manual, or they need to fix your engine.
Last edited by mc2; 06-17-2005 at 11:43 PM.
#25
06-17-2005, 11:39 PM
Originally Posted by trey's wife
Because it's like batteries, light bulbs and several other things in life - if the less expensive is no better than the expensive stuff then there is no way I am paying more for it. I'm cheap pure and simple. I like my money and I see no reason to spend the extra when it doesn't make a difference. Note my original reply that we have tried them all and have found what makes a difference in our car - so we will use it. Now I will also say that with no other vehicle I have owned has it made an ounce of difference. In those cases I think it is quite ridiculous to pay the extra for no extra benefit. Our family spends over $200 a month on gas with the cheap stuff and only one full time driver. That few dollars a tank adds up. IMHO - more money for no improvement = lack of thought BUT more money for notable improvement = reasonable.
FYI -
Anti Knock Index or AKI - The octane number you see at the pumps in the US equal to (R+M) /2 . This is the average of two octane numbers; the Research Octane Number (RON) and the Motor Octane Number (MON) .
Octane Number - A measure of the anti-knock characteristics of a given fuel. The octane number you see at the pumps is the average of two octane numbers; the Research Octane Number (RON) and the Motor Octane Number (MON). This number is sometimes referred to as the Anti Knock Index or AKI. Each of these octane numbers is determined by ASTM laboratory tests. Low-speed and low load knock characteristics are determined by the RON test method. The MON method tests high-speed, high load, high temperature situations, in practice these conditions exist during periods of high speed power accelerations, hill climbing, or any period of high power output (sounds like racing to me). Obviously the MON number will be lower, but it's the one racers should concern themselves with.
Anyone explain any difference between these two terms? Looks like the same to me.
FYI -
Anti Knock Index or AKI - The octane number you see at the pumps in the US equal to (R+M) /2 . This is the average of two octane numbers; the Research Octane Number (RON) and the Motor Octane Number (MON) .
Octane Number - A measure of the anti-knock characteristics of a given fuel. The octane number you see at the pumps is the average of two octane numbers; the Research Octane Number (RON) and the Motor Octane Number (MON). This number is sometimes referred to as the Anti Knock Index or AKI. Each of these octane numbers is determined by ASTM laboratory tests. Low-speed and low load knock characteristics are determined by the RON test method. The MON method tests high-speed, high load, high temperature situations, in practice these conditions exist during periods of high speed power accelerations, hill climbing, or any period of high power output (sounds like racing to me). Obviously the MON number will be lower, but it's the one racers should concern themselves with.
Anyone explain any difference between these two terms? Looks like the same to me.
Genereally speaking the AKI will be about 95% of the RON.
Last edited by mc2; 06-17-2005 at 11:45 PM.
#26
06-17-2005, 11:42 PM
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Originally Posted by trey.hutcheson
I have run many tanks each of 87, 89, and 93. Down here in an Alabama summer , I can tell you that my butt dyno can feel absolotely zero difference amongst the three grades. Hell, there's not even any difference in economy. The reason I changed to 93, the ONLY reason, is because of knock.
On a side note, I would be interested in seeing track slips of the same car running the different grades, preferably at the same location, on the same night, at or around the same ambient temps. I would be very suprised to see more than a few percentage points difference in accel times and trap speeds.
On a side note, I would be interested in seeing track slips of the same car running the different grades, preferably at the same location, on the same night, at or around the same ambient temps. I would be very suprised to see more than a few percentage points difference in accel times and trap speeds.
#27
06-17-2005, 11:45 PM
Originally Posted by allforthecash
I agree..performance may improve or it may stay the same..but if you can't feel the difference in engine smoothness,..knock, roughness, and ****ty idle....then continue using 89..your engine will thank u for it... heheheh
#28
06-17-2005, 11:50 PM
Originally Posted by BobbyG123
That's just it, the car WILL have issues if you run with regular octane. The ping you're hearing is more than just annoying.
'If fuel octane is too low for a given compression ratio, the fuel prematurely and spontaneously ignites too early and the fuel charge EXPLODES rather than BURNS resulting in incomplete combustion. The net effect is a loss in power and possible engine damage. The operator hears an audible "knock" or "ping", referred to as detonation. Detonation may vary from a faint noise on light acceleration to a constant, deep hammering noise while driving at a constant speed. Improper timing adjustments, vacuum leaks, or excessively lean fuel mixtures may also cause detonation."
Listen, I'm nearly 40 years old and don't care what octane level you choose to put in your car. My honest, objective opinion is that if the price of premium fuel is dictating whether or not you should use the CORRECT octane in your high compression sports car, you should consider trading in your vehicle. I'm not saying that to sound confrontational, but using the lower octane in a VQ engine is wrong. Period. I don't need to ask Infiniti for clarification either. Call some independent mechanics and run it by them. Tell them you own a Nissan 350Z (they'll be more familiar with it), you use regular octane gas, and get a lot of knocking and pinging. Then ask them if it's bad. Nuff' said.
'If fuel octane is too low for a given compression ratio, the fuel prematurely and spontaneously ignites too early and the fuel charge EXPLODES rather than BURNS resulting in incomplete combustion. The net effect is a loss in power and possible engine damage. The operator hears an audible "knock" or "ping", referred to as detonation. Detonation may vary from a faint noise on light acceleration to a constant, deep hammering noise while driving at a constant speed. Improper timing adjustments, vacuum leaks, or excessively lean fuel mixtures may also cause detonation."
Listen, I'm nearly 40 years old and don't care what octane level you choose to put in your car. My honest, objective opinion is that if the price of premium fuel is dictating whether or not you should use the CORRECT octane in your high compression sports car, you should consider trading in your vehicle. I'm not saying that to sound confrontational, but using the lower octane in a VQ engine is wrong. Period. I don't need to ask Infiniti for clarification either. Call some independent mechanics and run it by them. Tell them you own a Nissan 350Z (they'll be more familiar with it), you use regular octane gas, and get a lot of knocking and pinging. Then ask them if it's bad. Nuff' said.
I don't appreciate someone getting an attitude that someone is an idiot if they don't hold the same opinion - even if that is how they may feel 
Money isn't a reason to buy or not buy a particular type of gas. I was raised by a mechanic who was also what many call a "gearhead". He raced cars for years and built his own engines. His current business is still with engines. I don't consider myself ignorant about most things and I have discussed this with him. He had a small coronary that I was buying gas at the "generic" stations but other than that said that if the manual states that the car is ok with a lower octane then you aren't _hurting_ it provided it is high quality gas NOT FROM A GENERIC STATION (to enforce his opinion)
It may not provide the highest efficency but it will not damage the engine under normal "average" driving condition. For the record, I fully agree that the person who raised this question should definitely stay with the high octane to determine if that is the cause of the problem. When we did notice a knock we did something about it as I hope they will be able to do. We pay attention to our cars and I care about if my car runs properly - I will dare to say it that I am not a fanatic about everything with my car. If it runs properly, which the manual says it can and the dealership told us it would, with something other than 93 then that is an option. IF it doesn't then we stick with 93.
#29
06-18-2005, 12:38 PM
Originally Posted by mc2
You obviously have NO Idea what you are talking about. If you run a 93 Octane in a car designed for 87 octane you're going to get ****ty gas mileage and bog the engine because the spark that the car generates will be unable to ignite the fuel.. Octane is simply the fuels resistance to detonation.. If the car is not designed for it, higher octane is not going to result in better track times, better gas mileage, smoother ride... If you go to the track and put 100 Octane in your bone stock G35 and try to run that around it's going to do nothing for you.
It's not "As Always, the higher the octane the better"
I would put whatever the users manual suggests. If you are getting knock while still using what the manual suggests then either the Manufacturer needs to fix their manual, or they need to fix your engine.
It's not "As Always, the higher the octane the better"
I would put whatever the users manual suggests. If you are getting knock while still using what the manual suggests then either the Manufacturer needs to fix their manual, or they need to fix your engine.
As far as the 100 octane doing nothing – I’m not even going to comment because #1 I’ve never ran on it, and #2 it will open a whole other can of worms because I have read posts from users that have had good results with it.
In any event, fuel rated with higher rating is a better idea than fuel with too low octane. If you disagree, by all means run low octane.
#30
06-18-2005, 01:16 PM
Originally Posted by OCG35
Okay, let’s set the record straight… On the ‘04 sedan (at least mine) the inside filler door says “Premium fuel recommended for maximum performance”.
The owner’s manual (attached) says: 87 AKI (Anti-Knock Index) – Research Octane Number 91.
As always, the higher the octane the better… My question is: If you own one of the highest rated performance sedans (in many cases THE highest rated), why would you put sh!tty fuel in it?
The owner’s manual (attached) says: 87 AKI (Anti-Knock Index) – Research Octane Number 91.
As always, the higher the octane the better… My question is: If you own one of the highest rated performance sedans (in many cases THE highest rated), why would you put sh!tty fuel in it?
Do not confuse 2 different ways to measure octabe. Label says that 87(Regular) is OK. How the hell coupe owners suppose to find RON 96, if to follow your logic?
Fly to France each time they need gas?
Are those dumb octane/what is better oil questions ever gonna go away?
I DO NOT get knock with 87, because I live in colder Ontario. I use 94 because I like improved response.
If you are in hot Texas/California,then you are likely to get knock with 87, not because it "****ty", but because it is doesn't fit the purpose.
I should say that my Toyo T1R are "****ty", because I cannot use them in snow....G35 is crap, because I cannot do rock crawling in it..
Last edited by obender66; 06-18-2005 at 01:24 PM.