Premium gas vs regular
09-12-2006, 02:34 PM
#41
acura-cl.com OG
Originally Posted by leedogg
What about 93 vs 91? Anybody know if our cars will fully utilize 93?
around here sunoco is the only provider of 91 and the pricing is as follows:
87 2.80
89 2.90
91 2.95
93 3.00
hopefully someone knows the facts.....
09-12-2006, 03:13 PM
#42
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Regarding octane, the premium gas is actually harder to ignite therefore tolerating higher compressions and you get more power output. Cheaper gas actually has a lower flash point under higher compression therefore having spontaneous ignition before top dead center (producing the detrimental knock).
Most new cars do have knock sensors that in fact retard the timing to ignite the gas at a lower compression (to protect your engine). This does lower power output and the driver will inevitably push harder on the gas pedal to maintain drivability. This will in turn decrease your MPG.
This is a round about way of saying, pay for the correct octane. You will get the satisfaction of having the correct amount of power output, better MPG, fewer fill-ups, safer fuel for your car, and will ultimately spend the same if not less money in the long run.
Most new cars do have knock sensors that in fact retard the timing to ignite the gas at a lower compression (to protect your engine). This does lower power output and the driver will inevitably push harder on the gas pedal to maintain drivability. This will in turn decrease your MPG.
This is a round about way of saying, pay for the correct octane. You will get the satisfaction of having the correct amount of power output, better MPG, fewer fill-ups, safer fuel for your car, and will ultimately spend the same if not less money in the long run.
09-13-2006, 06:13 PM
#43
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Originally Posted by gonein60sec
For those who said that they researched the car and were never told by the salesman that the TL uses premium gas, it clearly states on the Acura website under General Specifications that the recommended fuel for the TL is Premium unleaded 91 octane.
My salesman told me that you can use 89 but you won't get the benefit of the ULEV-2 rating and that gas mileage might suffer somewhat using anything less than the recommended 91 octane.
My salesman told me that you can use 89 but you won't get the benefit of the ULEV-2 rating and that gas mileage might suffer somewhat using anything less than the recommended 91 octane.
09-13-2006, 09:05 PM
#44
Intermediate
Originally Posted by gurneyeagle
No not dumb! 
At an average of 20K miles driven annually at 25 mpg, at a price differential of $0.30 per gallon, the additional cost is $240 annually.
Someone worried about $250/yr, shouldn't be spending $35K on a car.
What are you guys seeing as the price differential between regular and premium. Here in the great cesspool known as New Orleans, it used to be $0.20, but has run up to $0.32 on average. Definitely supply/demand pricing going on here.
At an average of 20K miles driven annually at 25 mpg, at a price differential of $0.30 per gallon, the additional cost is $240 annually.
Someone worried about $250/yr, shouldn't be spending $35K on a car.
What are you guys seeing as the price differential between regular and premium. Here in the great cesspool known as New Orleans, it used to be $0.20, but has run up to $0.32 on average. Definitely supply/demand pricing going on here.
and how many of u are doin 20k miles and the doference between prices is not even that big usually so why buy 35k car if u have to worry about 250 a year - o u say u got bbills to pay and shit ? if u are that broke that cant pay bills why did u buy 35k car to begine with !!! should have bought something like a nice cheap kia ,(no offense to anyone intended)
and guys do research i just read it somewhere about gas comparison 93 to that cheap new gas and the rest -
more$ = more mpg
less money (cheaper gas) = less mpg
it comes out to be the same thing lol
09-13-2006, 09:08 PM
#45
Intermediate
well i do have a question about gas - what if u put some of that "octane booster" thing in your gas that makes it 108octane , and all those other ones that are pretty much the same thing or outcome more octane more power
does that stuff damage engine? short and longrun
does that stuff damage engine? short and longrun
09-13-2006, 10:14 PM
#46
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Originally Posted by groman
well i do have a question about gas - what if u put some of that "octane booster" thing in your gas that makes it 108octane , and all those other ones that are pretty much the same thing or outcome more octane more power
does that stuff damage engine? short and longrun
does that stuff damage engine? short and longrun
09-13-2006, 11:47 PM
#47
Drifting
Originally Posted by ubnpast
Im not sure about making it 108 octane, but it does in fact bring the octane up. If it was bad for your car they wouldnt be selling it (because they would get sued).
As for the octane booster, I wouldn't use it. I don't know about Acura, but GM specifially says not to use it. GM went so far as to say that the only fuel additive that is approved for use is Techron. I don't have the manuals in front of me, but I vaguely remember it saying that using other non-approved fuel additives may void your warranty. I know on other boards people have complained about a red residue on everything from the octane booster.
Besides, from what I remember, the cost of the octane booster is more expensive than just buying premium. Especially because I remember someone saying that the 108+ booster is using a different scale than on the pumps. I can't remember what the scale difference was, but I seem to remember someone saying it would effectively turn 87 octane into 88 or 89 octane or something, not 108 like many would believe. I could be wrong, but that's what I remember....
09-14-2006, 01:45 AM
#48
do not use octane boosters, they have very little real world value. I noticed the car ran better on 91 vs 89, time for me to try 93. On 91, for the last 1002 miles i got an average of 28mpg (avg mph was like 53 i think) mostly crusing but some city driving, as well as some high speed pulls (few blasts to 120, cruising 75-90) chevron Techron is a very good injector cleaner (works great in pretty much anything)
09-14-2006, 02:05 AM
#49
Randy is the Future
Originally Posted by BruceLandry
But was it primium Alcohol or cheap regular Alcohol 
LMAO LOL halirious
09-14-2006, 04:16 AM
#50
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Originally Posted by EternaLlx
and regular gas cost you more in the long run cause we lose MPG as someone has tested here.
I got my 06TL-auto in May and have been using 89 gas since I got the car with the exception of one tank of 91 and one tank of 87(by accident - used to hitting the 87 button with the old car). I couldn't decide if I should spend the extra money to use 91, but I also didn't want to be cheap on the car so I just compromised. I don't race my car or floor it so I didn't notice any difference in performance. I drive local to and from work daily and get only about 17-18mpg. But when I visit my parents I have gotten 31mpg doing about 75mph on the freeway for 250 miles. This was at night with the AC on. So far things have been fine for me so I plan to stick to 89 until some other discussion convinces me otherwise.
For the issue of people being able to afford 91 octane gas cause they drive a 35k car, let me put in my
and just say that who says just because a person is rich they should just throw away their money? Would a successful business be as successful if they didn't try to cut costs where they can to increase profits? $250/year saved is $250/year towards something else, ie 6 months of cell phone bills, cable bills, electricity bills, free food for a month...etc. Learning to save at a time when there is so much debt in this country can be a good thing. 
09-14-2006, 09:03 AM
#51
Drifting
Originally Posted by count by 5s
For the issue of people being able to afford 91 octane gas cause they drive a 35k car, let me put in my and just say that who says just because a person is rich they should just throw away their money? Would a successful business be as successful if they didn't try to cut costs where they can to increase profits? $250/year saved is $250/year towards something else, ie 6 months of cell phone bills, cable bills, electricity bills, free food for a month...etc. Learning to save at a time when there is so much debt in this country can be a good thing.
and just say that who says just because a person is rich they should just throw away their money? Would a successful business be as successful if they didn't try to cut costs where they can to increase profits? $250/year saved is $250/year towards something else, ie 6 months of cell phone bills, cable bills, electricity bills, free food for a month...etc. Learning to save at a time when there is so much debt in this country can be a good thing. Yes, I understand how you run a business. Most businesses look at expenses in relative terms. For example, if a company purchases a multi-million dollar contract, they are not going to quibble over a few thousand dollars.
Likewise, if you buy a $500,000 house, arguing with the seller over $300 is retarded.
The difference for me between filling up with 91 and 87 is like $2.50 a tank. It costs me more to park the car downtown. If I wanted to save that money, I would find street parking instead of always using the structures downtown.
I also always buy an energy drink on my lunch break. That costs $2.50. I could save that by not buying that either.
09-14-2006, 09:09 AM
#52
Drifting
<sarcasm>
You can probably save more money buy buying your medication meant for horses. Sure it ain't FDA approved for humans, but it's the same drug right? Can't be any worse than using 87 instead of 91, eh?
</sarcasm>
You can probably save more money buy buying your medication meant for horses. Sure it ain't FDA approved for humans, but it's the same drug right? Can't be any worse than using 87 instead of 91, eh?
</sarcasm>
09-14-2006, 05:49 PM
#55
Three Wheelin'
Originally Posted by groman
well i do have a question about gas - what if u put some of that "octane booster" thing in your gas that makes it 108octane , and all those other ones that are pretty much the same thing or outcome more octane more power
does that stuff damage engine? short and longrun
does that stuff damage engine? short and longrun
Now if you're running real 108 octane race gas, yes it has the potential to damage your car long term. The chemical composition of race gas (even unleaded) it significantly different and could potentially hard rubber seals, sensors etc that arent designed with it in mind.
09-15-2006, 05:46 AM
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Originally Posted by avs007
<sarcasm>
You can probably save more money buy buying your medication meant for horses. Sure it ain't FDA approved for humans, but it's the same drug right? Can't be any worse than using 87 instead of 91, eh?
</sarcasm>
You can probably save more money buy buying your medication meant for horses. Sure it ain't FDA approved for humans, but it's the same drug right? Can't be any worse than using 87 instead of 91, eh?
</sarcasm>
I agree with your points above and I can definitely see both sides of money saving on gas. I'm consistent in my money saving so actually I do everything that you've mentioned above (though with the toilet paper...I spend the extra dollar for softness for that sensitive area
) I just think it's wrong to say that you shouldn't drive this car if you can't afford 91 octane gas. If that's the case, why do I see BMW's or Benz's lined up at Costco gas stations for cheaper gas? People have different financial situations so I don't think someone should be criticized for trying to save at the pump. Personally I have no problem paying for 91 octane, but as I have mentioned before, I'm not completely convinced that it is necessary and don't see the performance gain myself, so I'm gonna stick to the middle. My Dad's car is a 92 Acura Legend which says 'premium fuel' on the fuel gauge but he's been pumping 87 gas forever. The car has 150k miles on it and is running perfectly. Makes me wonder if the premium is really necessary. You're right that it's useless to argue over $300 on a $500,000 house, but if that $300 was for an upgraded doorknob, is it still worth it? It all depends. There is no right or wrong answer.
Anyway I'm still wondering if someone can clear up my question in my previous post.... higher octane = better mpg or worse? If higher octane = better mileage then that might be good enough reason for me to go with 91!
09-15-2006, 11:57 PM
#58
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I just don't understand why people always agree about this... If you wanted to use regular than why didn't you buy a ford or something else. If gas prices is to high for you now days than friggen trade your car in for a ford focus or something with good gas mileage. Don't go the cheap route and later post question about why my engine is knocking and etc... It say in the manual to used 91 or higher.
Argue all you want about it...Read the manual since you pay for it.
Argue all you want about it...Read the manual since you pay for it.
09-17-2006, 03:19 AM
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Originally Posted by thisguymo
91 higher gets you more mpg than 87. Using 87 on the TL engine will make the engine go into "safe" mode and reduce performance and mpg.
09-18-2006, 02:57 PM
#60
In the TL the compression is 11:1 which is pretty high, and lower than 91 octane makes it succeptable to knocking /pinging (hard to hear in this car) so the computer pulls out ignition timing to save the engine from damage. This can hurt mpg and performance by a noticeable margin, as the engine wasnt designed to run on crappy gas
09-18-2006, 10:04 PM
#61
Has it been a month already?
We do this topic once a month!
Let me refresh your memories with a previous post I made.
The HIGHER the octane (RON), the LESS Volatile the gasoline. Period. If you think different, you are wrong.
Higher octane fuels are used to prevent pre-ignition, ping and/or knock. Why do they prevent pre-ignition, ping and knock? Simple, they resist the initial burn and are less volatile. Higher octane fuels DO NOT mean or equal more power, torque and/or fuel economy. They just do not work like that.
High compression ratio engines, turbocharged or supercharged engines are all KNOCK constrained. What determines this is the cylinder pressures. As the cylinder pressure rises, the need for more octane is required.
Heptane which is technically gasoline has a chemically correct formula of 14.64:1 (some of you say 14.7:1 which is fine). Octane is an organic compound that is added to heptane to DECREASE the volatility of the fuel. Lead was added to fuels to decrease the volatility as well. We don't use leaded fuels in late model pollution control vehicles and longer.
For one, lead is very environmentally unfriendly. The lead will react to the catalyst in the catalytic converters and ruin oxygen sensors. I can't imagine lead would be friendly for the new pintle style fuel injectors as well.
Some of you will argue with me and tell me how you car feels "faster" with HIGH octane gasoline or race fuel. That's fine, but the STOP (seat of the pants) meter is almost always wrong.
Most cars with KS (knock sensors) detect the onset of knock well before a human can hear it. The frequency of vibration triggers the KS to retard the spark timing. 1 degree of spark on a supercharged engine is worth approx 4-5 HP and 5-10 lb.-ft of torque.
An example, so if you have an engine that requires 91 octane fuel and you are using 87 octane the KS might be activated. The computer pulls 3 degrees of spark timing and you've just lost 5-6 HP (n/a engine is worth about half the power depending on the engine). Then you decide to try 93 octane and poof...the car feels faster. Did you make any more power? No, you made the power you should have been making all along. Except now the KS isn't being tripped.
If you added 100 octane unleaded fuel to you stock TL it will not make any more power or run a faster 1/4 mile time. NO WAY...NO HOW!
The only way to make the engine respond to the increased octane would be to tune it and add more spark timing (if possible at all). Perhaps a 2-3 degrees more spark could be added, but it depends on the engine dynamics. Would the ECM detect the additional octane and increase the spark on it's own...NO.
I've seen Lincoln Mark VIII guys pull this magic trick on the dyno and claim more octane means more power. The Mark VIII uses a 4.6L DOHC V-8 and by default the engine is knock constrained right from the factory. As a Ford engineer once told me, those cars are almost always into the KS right off the showroom floor.
So add 100 octane fuel, 1 heat range colder spark plugs and a 180 degree t-stat and boom the car made an additional 10-15 RWHP on the dyno. Or did it? No not exactly. The power is usually exactly where it should be but without triggering the KS to activate.
Should you even consider high octane fuel for your stock TL? If you do you are just wasting your money. 91 octane is recommended and that is what you should use unless the engine pings or knocks. Then you move up a notch.
Also please don't argue about alcohol based fuels being the best thing since sliced bread. Please consider what it takes to even produce E85. Lot's of electricity is required to turn your favorite ear of corn into fuel for your car. Where does the electricity come from? Think about it.
There are many disadvantages to using alcohols, particularly methyl and ethyl alcohol. When used near their stoichiometric air/fuel ratios can produce more power, however a much...much larger quantity of fuel is required. Why?
Alcohol has a chemically correct formula of 9:1. So you need nearly twice as much to produce the same results at stoich. Yes that's right. So if a gallon of gasoline is $4.00 and a gallon of E85 is $2.00 but you are using twice as much E85 than gasoline, what have you gained?
Yeah its a way to get away from using 100% fossil fuels and the combustion process is cleaner then straight gasoline. Cost wise and energy wise...no it won't save you a penny.
Some of you will remember Vapor Lock. The relatively low boiling points and high vapor pressures of alcohol based fuels would cause problems with vapor lock, especially on a hot day.
Alcohol is higher corrosive and tends to absorb water. This means the fuel systems would have to be upgraded to deal with the corrosiveness of alcohol based fuels. Even been to a track and seen an alcohol fuel race car? Ask those racers how often they have to change their fuel lines and rails.
A-Train
Let me refresh your memories with a previous post I made.
The HIGHER the octane (RON), the LESS Volatile the gasoline. Period. If you think different, you are wrong.
Higher octane fuels are used to prevent pre-ignition, ping and/or knock. Why do they prevent pre-ignition, ping and knock? Simple, they resist the initial burn and are less volatile. Higher octane fuels DO NOT mean or equal more power, torque and/or fuel economy. They just do not work like that.
High compression ratio engines, turbocharged or supercharged engines are all KNOCK constrained. What determines this is the cylinder pressures. As the cylinder pressure rises, the need for more octane is required.
Heptane which is technically gasoline has a chemically correct formula of 14.64:1 (some of you say 14.7:1 which is fine). Octane is an organic compound that is added to heptane to DECREASE the volatility of the fuel. Lead was added to fuels to decrease the volatility as well. We don't use leaded fuels in late model pollution control vehicles and longer.
For one, lead is very environmentally unfriendly. The lead will react to the catalyst in the catalytic converters and ruin oxygen sensors. I can't imagine lead would be friendly for the new pintle style fuel injectors as well.
Some of you will argue with me and tell me how you car feels "faster" with HIGH octane gasoline or race fuel. That's fine, but the STOP (seat of the pants) meter is almost always wrong.
Most cars with KS (knock sensors) detect the onset of knock well before a human can hear it. The frequency of vibration triggers the KS to retard the spark timing. 1 degree of spark on a supercharged engine is worth approx 4-5 HP and 5-10 lb.-ft of torque.
An example, so if you have an engine that requires 91 octane fuel and you are using 87 octane the KS might be activated. The computer pulls 3 degrees of spark timing and you've just lost 5-6 HP (n/a engine is worth about half the power depending on the engine). Then you decide to try 93 octane and poof...the car feels faster. Did you make any more power? No, you made the power you should have been making all along. Except now the KS isn't being tripped.
If you added 100 octane unleaded fuel to you stock TL it will not make any more power or run a faster 1/4 mile time. NO WAY...NO HOW!
The only way to make the engine respond to the increased octane would be to tune it and add more spark timing (if possible at all). Perhaps a 2-3 degrees more spark could be added, but it depends on the engine dynamics. Would the ECM detect the additional octane and increase the spark on it's own...NO.
I've seen Lincoln Mark VIII guys pull this magic trick on the dyno and claim more octane means more power. The Mark VIII uses a 4.6L DOHC V-8 and by default the engine is knock constrained right from the factory. As a Ford engineer once told me, those cars are almost always into the KS right off the showroom floor.
So add 100 octane fuel, 1 heat range colder spark plugs and a 180 degree t-stat and boom the car made an additional 10-15 RWHP on the dyno. Or did it? No not exactly. The power is usually exactly where it should be but without triggering the KS to activate.
Should you even consider high octane fuel for your stock TL? If you do you are just wasting your money. 91 octane is recommended and that is what you should use unless the engine pings or knocks. Then you move up a notch.
Also please don't argue about alcohol based fuels being the best thing since sliced bread. Please consider what it takes to even produce E85. Lot's of electricity is required to turn your favorite ear of corn into fuel for your car. Where does the electricity come from? Think about it.
There are many disadvantages to using alcohols, particularly methyl and ethyl alcohol. When used near their stoichiometric air/fuel ratios can produce more power, however a much...much larger quantity of fuel is required. Why?
Alcohol has a chemically correct formula of 9:1. So you need nearly twice as much to produce the same results at stoich. Yes that's right. So if a gallon of gasoline is $4.00 and a gallon of E85 is $2.00 but you are using twice as much E85 than gasoline, what have you gained?
Yeah its a way to get away from using 100% fossil fuels and the combustion process is cleaner then straight gasoline. Cost wise and energy wise...no it won't save you a penny.
Some of you will remember Vapor Lock. The relatively low boiling points and high vapor pressures of alcohol based fuels would cause problems with vapor lock, especially on a hot day.
Alcohol is higher corrosive and tends to absorb water. This means the fuel systems would have to be upgraded to deal with the corrosiveness of alcohol based fuels. Even been to a track and seen an alcohol fuel race car? Ask those racers how often they have to change their fuel lines and rails.
A-Train
09-19-2006, 07:10 AM
#63
Registered Member
Originally Posted by Atrain
We do this topic once a month!
Let me refresh your memories with a previous post I made.
The HIGHER the octane (RON), the LESS Volatile the gasoline. Period. If you think different, you are wrong.
Higher octane fuels are used to prevent pre-ignition, ping and/or knock. Why do they prevent pre-ignition, ping and knock? Simple, they resist the initial burn and are less volatile. Higher octane fuels DO NOT mean or equal more power, torque and/or fuel economy. They just do not work like that.
High compression ratio engines, turbocharged or supercharged engines are all KNOCK constrained. What determines this is the cylinder pressures. As the cylinder pressure rises, the need for more octane is required.
Heptane which is technically gasoline has a chemically correct formula of 14.64:1 (some of you say 14.7:1 which is fine). Octane is an organic compound that is added to heptane to DECREASE the volatility of the fuel. Lead was added to fuels to decrease the volatility as well. We don't use leaded fuels in late model pollution control vehicles and longer.
For one, lead is very environmentally unfriendly. The lead will react to the catalyst in the catalytic converters and ruin oxygen sensors. I can't imagine lead would be friendly for the new pintle style fuel injectors as well.
Some of you will argue with me and tell me how you car feels "faster" with HIGH octane gasoline or race fuel. That's fine, but the STOP (seat of the pants) meter is almost always wrong.
Most cars with KS (knock sensors) detect the onset of knock well before a human can hear it. The frequency of vibration triggers the KS to retard the spark timing. 1 degree of spark on a supercharged engine is worth approx 4-5 HP and 5-10 lb.-ft of torque.
An example, so if you have an engine that requires 91 octane fuel and you are using 87 octane the KS might be activated. The computer pulls 3 degrees of spark timing and you've just lost 5-6 HP (n/a engine is worth about half the power depending on the engine). Then you decide to try 93 octane and poof...the car feels faster. Did you make any more power? No, you made the power you should have been making all along. Except now the KS isn't being tripped.
If you added 100 octane unleaded fuel to you stock TL it will not make any more power or run a faster 1/4 mile time. NO WAY...NO HOW!
The only way to make the engine respond to the increased octane would be to tune it and add more spark timing (if possible at all). Perhaps a 2-3 degrees more spark could be added, but it depends on the engine dynamics. Would the ECM detect the additional octane and increase the spark on it's own...NO.
I've seen Lincoln Mark VIII guys pull this magic trick on the dyno and claim more octane means more power. The Mark VIII uses a 4.6L DOHC V-8 and by default the engine is knock constrained right from the factory. As a Ford engineer once told me, those cars are almost always into the KS right off the showroom floor.
So add 100 octane fuel, 1 heat range colder spark plugs and a 180 degree t-stat and boom the car made an additional 10-15 RWHP on the dyno. Or did it? No not exactly. The power is usually exactly where it should be but without triggering the KS to activate.
Should you even consider high octane fuel for your stock TL? If you do you are just wasting your money. 91 octane is recommended and that is what you should use unless the engine pings or knocks. Then you move up a notch.
Also please don't argue about alcohol based fuels being the best thing since sliced bread. Please consider what it takes to even produce E85. Lot's of electricity is required to turn your favorite ear of corn into fuel for your car. Where does the electricity come from? Think about it.
There are many disadvantages to using alcohols, particularly methyl and ethyl alcohol. When used near their stoichiometric air/fuel ratios can produce more power, however a much...much larger quantity of fuel is required. Why?
Alcohol has a chemically correct formula of 9:1. So you need nearly twice as much to produce the same results at stoich. Yes that's right. So if a gallon of gasoline is $4.00 and a gallon of E85 is $2.00 but you are using twice as much E85 than gasoline, what have you gained?
Yeah its a way to get away from using 100% fossil fuels and the combustion process is cleaner then straight gasoline. Cost wise and energy wise...no it won't save you a penny.
Some of you will remember Vapor Lock. The relatively low boiling points and high vapor pressures of alcohol based fuels would cause problems with vapor lock, especially on a hot day.
Alcohol is higher corrosive and tends to absorb water. This means the fuel systems would have to be upgraded to deal with the corrosiveness of alcohol based fuels. Even been to a track and seen an alcohol fuel race car? Ask those racers how often they have to change their fuel lines and rails.
A-Train
Let me refresh your memories with a previous post I made.
The HIGHER the octane (RON), the LESS Volatile the gasoline. Period. If you think different, you are wrong.
Higher octane fuels are used to prevent pre-ignition, ping and/or knock. Why do they prevent pre-ignition, ping and knock? Simple, they resist the initial burn and are less volatile. Higher octane fuels DO NOT mean or equal more power, torque and/or fuel economy. They just do not work like that.
High compression ratio engines, turbocharged or supercharged engines are all KNOCK constrained. What determines this is the cylinder pressures. As the cylinder pressure rises, the need for more octane is required.
Heptane which is technically gasoline has a chemically correct formula of 14.64:1 (some of you say 14.7:1 which is fine). Octane is an organic compound that is added to heptane to DECREASE the volatility of the fuel. Lead was added to fuels to decrease the volatility as well. We don't use leaded fuels in late model pollution control vehicles and longer.
For one, lead is very environmentally unfriendly. The lead will react to the catalyst in the catalytic converters and ruin oxygen sensors. I can't imagine lead would be friendly for the new pintle style fuel injectors as well.
Some of you will argue with me and tell me how you car feels "faster" with HIGH octane gasoline or race fuel. That's fine, but the STOP (seat of the pants) meter is almost always wrong.
Most cars with KS (knock sensors) detect the onset of knock well before a human can hear it. The frequency of vibration triggers the KS to retard the spark timing. 1 degree of spark on a supercharged engine is worth approx 4-5 HP and 5-10 lb.-ft of torque.
An example, so if you have an engine that requires 91 octane fuel and you are using 87 octane the KS might be activated. The computer pulls 3 degrees of spark timing and you've just lost 5-6 HP (n/a engine is worth about half the power depending on the engine). Then you decide to try 93 octane and poof...the car feels faster. Did you make any more power? No, you made the power you should have been making all along. Except now the KS isn't being tripped.
If you added 100 octane unleaded fuel to you stock TL it will not make any more power or run a faster 1/4 mile time. NO WAY...NO HOW!
The only way to make the engine respond to the increased octane would be to tune it and add more spark timing (if possible at all). Perhaps a 2-3 degrees more spark could be added, but it depends on the engine dynamics. Would the ECM detect the additional octane and increase the spark on it's own...NO.
I've seen Lincoln Mark VIII guys pull this magic trick on the dyno and claim more octane means more power. The Mark VIII uses a 4.6L DOHC V-8 and by default the engine is knock constrained right from the factory. As a Ford engineer once told me, those cars are almost always into the KS right off the showroom floor.
So add 100 octane fuel, 1 heat range colder spark plugs and a 180 degree t-stat and boom the car made an additional 10-15 RWHP on the dyno. Or did it? No not exactly. The power is usually exactly where it should be but without triggering the KS to activate.
Should you even consider high octane fuel for your stock TL? If you do you are just wasting your money. 91 octane is recommended and that is what you should use unless the engine pings or knocks. Then you move up a notch.
Also please don't argue about alcohol based fuels being the best thing since sliced bread. Please consider what it takes to even produce E85. Lot's of electricity is required to turn your favorite ear of corn into fuel for your car. Where does the electricity come from? Think about it.
There are many disadvantages to using alcohols, particularly methyl and ethyl alcohol. When used near their stoichiometric air/fuel ratios can produce more power, however a much...much larger quantity of fuel is required. Why?
Alcohol has a chemically correct formula of 9:1. So you need nearly twice as much to produce the same results at stoich. Yes that's right. So if a gallon of gasoline is $4.00 and a gallon of E85 is $2.00 but you are using twice as much E85 than gasoline, what have you gained?
Yeah its a way to get away from using 100% fossil fuels and the combustion process is cleaner then straight gasoline. Cost wise and energy wise...no it won't save you a penny.
Some of you will remember Vapor Lock. The relatively low boiling points and high vapor pressures of alcohol based fuels would cause problems with vapor lock, especially on a hot day.
Alcohol is higher corrosive and tends to absorb water. This means the fuel systems would have to be upgraded to deal with the corrosiveness of alcohol based fuels. Even been to a track and seen an alcohol fuel race car? Ask those racers how often they have to change their fuel lines and rails.
A-Train
"The HIGHER the octane (RON), the LESS Volatile the gasoline. Period. [/B] If you think different, you are wrong."
I have been arguing this same topic for years with people and you'd be amazed at how many of them (mostly men) STILL believe that by going to a higher octane fuel grade, they get more power and better mileage. Unless something has occurred in the interim (such as changing the state of tune of the engine), this just ain't going to happen. In fact, the reverse will occur.
Thank you A-Train. Excellent post.
09-20-2006, 05:33 AM
#66
Registered Member
In my neck of the woods, a few stations are selling regular at just over $1.90. And the Amoco (BP) where I go sells 93 at $2.419 (as of yesterday afternoon). It will be around $2.34 on Thursday.
09-20-2006, 10:45 AM
#67
Three Wheelin'
Originally Posted by SouthernBoy
Gentlemen. Listen to A-Train here. He is dead on correct with his post. Especially with his initial assertion of,
"The HIGHER the octane (RON), the LESS Volatile the gasoline. Period. [/B] If you think different, you are wrong."
I have been arguing this same topic for years with people and you'd be amazed at how many of them (mostly men) STILL believe that by going to a higher octane fuel grade, they get more power and better mileage. Unless something has occurred in the interim (such as changing the state of tune of the engine), this just ain't going to happen. In fact, the reverse will occur.
Thank you A-Train. Excellent post.
"The HIGHER the octane (RON), the LESS Volatile the gasoline. Period. [/B] If you think different, you are wrong."
I have been arguing this same topic for years with people and you'd be amazed at how many of them (mostly men) STILL believe that by going to a higher octane fuel grade, they get more power and better mileage. Unless something has occurred in the interim (such as changing the state of tune of the engine), this just ain't going to happen. In fact, the reverse will occur.
Thank you A-Train. Excellent post.
One thing Ive found interesting on car boards, is how many car myths and tuning ideas have carried on from the 50-60-70's to today's EFI cars. For example, reving the engine before shutting it off. Makes sense on a carburated car, but not now.
Oh yah, and the whole torque vs hp arguement. If I had a nickle everytime I had someone make wildly incorrect assertions about that......
09-20-2006, 11:26 AM
#68
id like to think that since acura requires 91 oct then there would be little if any gain going to 93. I tried it myself and didnt notice a difference, but going from 89 to 91 i did. If we could creep inside the ecu and see the knock counts then we could really make an absolute statement about it
09-20-2006, 11:38 AM
#69
Safety Car
Originally Posted by SouthernBoy
Gentlemen. Listen to A-Train here. He is dead on correct with his post. Especially with his initial assertion of,
"The HIGHER the octane (RON), the LESS Volatile the gasoline. Period. [/B] If you think different, you are wrong."
I have been arguing this same topic for years with people and you'd be amazed at how many of them (mostly men) STILL believe that by going to a higher octane fuel grade, they get more power and better mileage. Unless something has occurred in the interim (such as changing the state of tune of the engine), this just ain't going to happen. In fact, the reverse will occur.
Thank you A-Train. Excellent post.
"The HIGHER the octane (RON), the LESS Volatile the gasoline. Period. [/B] If you think different, you are wrong."
I have been arguing this same topic for years with people and you'd be amazed at how many of them (mostly men) STILL believe that by going to a higher octane fuel grade, they get more power and better mileage. Unless something has occurred in the interim (such as changing the state of tune of the engine), this just ain't going to happen. In fact, the reverse will occur.
Thank you A-Train. Excellent post.
Higher Octane fuels do get a car more power if the car was designed for higher octane fuels like our TL is and the G35 I use to have.
The TL/G35 requires 91+ Octane. Here in Texas we have 87,89,93 octane. So they get 93 octane.
I have seen on my G35 only (never tried it on the TL yet), that when I put 87 octane fuel in the car, it lost a good amount of power (due to the knock sensors pulling timing back). This also has been test proven on a track and dyno. The G35 actually lost 15 hp~ compared to having 93 octane.
But, if you go with anything higher than 91-93 octane you will not notice a difference in power normally.
09-20-2006, 05:24 PM
#70
Registered Member
Originally Posted by geekybiker
True to a point. Yes high octane mean less volatile, but both of you assume that there is no advance left to give when using 91. That may or may not be the case on any given car. Oh, and FWIW we dont use RON. We use (RON+MON)/2. That means the octane ratings in the US can't be compared directly to those overseas.
One thing Ive found interesting on car boards, is how many car myths and tuning ideas have carried on from the 50-60-70's to today's EFI cars. For example, reving the engine before shutting it off. Makes sense on a carburated car, but not now.
Oh yah, and the whole torque vs hp arguement. If I had a nickle everytime I had someone make wildly incorrect assertions about that......
One thing Ive found interesting on car boards, is how many car myths and tuning ideas have carried on from the 50-60-70's to today's EFI cars. For example, reving the engine before shutting it off. Makes sense on a carburated car, but not now.
Oh yah, and the whole torque vs hp arguement. If I had a nickle everytime I had someone make wildly incorrect assertions about that......
The concept of revving the engine of a carbureted car and shutting off the ignition as you are doing this is a myth. This was never recommended in 60's cars and I would be quite surprised that it was for 50's models. The thought behind this was that a sufficient charge of raw fuel would be drawn into the engine to act as an aid to starting it the next time around. This is hogwash. In fact, it is detrimental to the engine because a fair amount of raw fuel will make its way into the cylinders and will wash oil from the rings and walls and contaminate the oil in the crankcase. Also, this practice will wet the plugs. When people did this, it was generally because other problems existed.
As for torque vs horsepower, one is a constant (though widely varying) twisting force while the other is a measurement of work performed over time. I have also had a time of it trying to explain this one, too.
09-20-2006, 06:15 PM
#71
Pro
Join Date: Sep 2004
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The real concern and bottom line that is at issue is "what is the price difference between regular and premium." If they are the same, I am quite sure that everyone will put premium in their car. Now that the price of gas is dropping, the difference between grades is also shrinking. Come on, folks, let's enjoy the "low price" while we can, and take our TLs on the road for a nice spin!!
09-20-2006, 07:00 PM
#72
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Join Date: Sep 2006
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Read This!!!!!!!!
The main advantage of premium-grade gas is that it allows automakers to advertise a few more horsepower by designing and tuning engines to take advantage of premium's anti-knock properties. But auto engineers generally agree that if you use regular in a premium engine, the power loss is so slight, most drivers can't tell.
"I go back and forth, and I'm hard-pressed to notice" whether there's regular or premium in the tank, says Jeff Jetter, principal chemist at Honda Research and Development Americas. He drives an Acura designed for premium.
Import brands, especially, use premium fuel to distinguish their upmarket models. Most Toyotas, for instance, are designed to run on regular or midgrade, while the automaker's Lexus luxury brand prefers premium. Same with Honda and its Acura luxury line.
"Generally, the more expensive the vehicle, the higher the expectation for performance and the more the customer is willing to pay for fuel," says Pete Haidos, head of product planning for Nissan in the USA.
Actually, the price debate is nearly worthless. At 20 cents more for premium, pumping 20 gallons of it instead of regular would cost $4 more. Annually, that's a difference of $171 for a vehicle that averages 14 miles per gallon — as some big sport-utility vehicles do — and is driven 12,000 miles a year.
Gasoline retailers and refiners like high-test because it's more profitable than regular-grade gas is. The retailer paid about 8 cents more for the premium you pay 20 cents more for — though that margin can swing wildly. Refiners make a few cents a gallon more on premium than on regular when they sell to wholesale distributors.
As long as it's clean
Profit is meaningless to the modern engine, which, regardless of what's specified in the owner's manual, hardly cares what you use — as long as it's clean.
Today's engines use highly evolved versions of a device called a knock sensor to adjust settings automatically for low-octane gas. And more engine control computers have adequate memory to allow separate sets of instructions for various octanes. The engine control computers keep pushing to maximize performance on whatever grade of fuel is used.
Extreme pressure inside the cylinders causes knock, which is the sound of the pistons literally rattling inside the cylinders. Too much too long can damage the engine. A little now and then won't.
The only modern engines that should really need premium are those with superchargers, which force-feed fuel into the cylinders. "You're driving along and just tramp the gas and the knock sensor cannot sense the knock fast enough in some cases," because the supercharger boosts pressure so fast, says Bob Furey, chemist and fuels specialist at General Motors.
Burning regular when the owner's manual specifies premium won't void the warranty, nor damage the engine, even the most finicky automakers say. "You're giving up perhaps just a little bit of performance that a customer wouldn't really even notice, it's so slight," says Furey.
Automakers say they don't test premium engines on regular to check the difference, but some auto engineers estimate that power declines roughly 5%.
"We can't guarantee the vehicle will perform as specified if other than premium fuel is used," says Mercedes-Benz spokeswoman Michelle Murad. All U.S. Mercedes engines specify premium.
All Porsche engines are designed for premium, too, but it's not available everywhere. "Our cars must be able to drive all over the world, and so we are able to run on regular," says Jakob Neusser, director of powertrain development at Porsche's research and development center in Weissach, Germany. "You don't have to feel that a mechanical problem or anything else will happen" using regular gas, even in the highest-performance, regular-production Porsches.
Premium, in fact, sometimes is worse fuel than regular. It resists knock because it's harder to ignite than lower-octane fuels. As a result, some engines won't start as quickly or run as smoothly on premium, notes Gibbs, the SAE fuel expert.
High-test does have a potential fuel economy benefit. It is slightly denser than lower-octane gas, meaning there's a little more energy in a gallon. But the small difference is hard to measure in real-world use, and that same density can contribute to undesirable buildup of waste products inside the engine.
No data show that engines designed strictly for regular run better or longer on premium.
The Federal Trade Commission, in a consumer notice, emphasizes: "(I)n most cases, using a higher-octane gasoline than your owner's manual recommends offers absolutely no benefit. It won't make your car perform better, go faster, get better mileage or run cleaner."
There is "no way of taking advantage of premium in a regular-grade car," says Furey.
"There is no gain. You're wasting money," insists Jim Blenkarn, in charge of powertrains at Nissan in the USA.
"No customer should ever be deluded into thinking there's any value in buying a higher grade of octane than we specify," says Toyota's Paul Williamsen, technical expert and trainer.
But premium retains a mystique.
"I go back and forth, and I'm hard-pressed to notice" whether there's regular or premium in the tank, says Jeff Jetter, principal chemist at Honda Research and Development Americas. He drives an Acura designed for premium.
Import brands, especially, use premium fuel to distinguish their upmarket models. Most Toyotas, for instance, are designed to run on regular or midgrade, while the automaker's Lexus luxury brand prefers premium. Same with Honda and its Acura luxury line.
"Generally, the more expensive the vehicle, the higher the expectation for performance and the more the customer is willing to pay for fuel," says Pete Haidos, head of product planning for Nissan in the USA.
Actually, the price debate is nearly worthless. At 20 cents more for premium, pumping 20 gallons of it instead of regular would cost $4 more. Annually, that's a difference of $171 for a vehicle that averages 14 miles per gallon — as some big sport-utility vehicles do — and is driven 12,000 miles a year.
Gasoline retailers and refiners like high-test because it's more profitable than regular-grade gas is. The retailer paid about 8 cents more for the premium you pay 20 cents more for — though that margin can swing wildly. Refiners make a few cents a gallon more on premium than on regular when they sell to wholesale distributors.
As long as it's clean
Profit is meaningless to the modern engine, which, regardless of what's specified in the owner's manual, hardly cares what you use — as long as it's clean.
Today's engines use highly evolved versions of a device called a knock sensor to adjust settings automatically for low-octane gas. And more engine control computers have adequate memory to allow separate sets of instructions for various octanes. The engine control computers keep pushing to maximize performance on whatever grade of fuel is used.
Extreme pressure inside the cylinders causes knock, which is the sound of the pistons literally rattling inside the cylinders. Too much too long can damage the engine. A little now and then won't.
The only modern engines that should really need premium are those with superchargers, which force-feed fuel into the cylinders. "You're driving along and just tramp the gas and the knock sensor cannot sense the knock fast enough in some cases," because the supercharger boosts pressure so fast, says Bob Furey, chemist and fuels specialist at General Motors.
Burning regular when the owner's manual specifies premium won't void the warranty, nor damage the engine, even the most finicky automakers say. "You're giving up perhaps just a little bit of performance that a customer wouldn't really even notice, it's so slight," says Furey.
Automakers say they don't test premium engines on regular to check the difference, but some auto engineers estimate that power declines roughly 5%.
"We can't guarantee the vehicle will perform as specified if other than premium fuel is used," says Mercedes-Benz spokeswoman Michelle Murad. All U.S. Mercedes engines specify premium.
All Porsche engines are designed for premium, too, but it's not available everywhere. "Our cars must be able to drive all over the world, and so we are able to run on regular," says Jakob Neusser, director of powertrain development at Porsche's research and development center in Weissach, Germany. "You don't have to feel that a mechanical problem or anything else will happen" using regular gas, even in the highest-performance, regular-production Porsches.
Premium, in fact, sometimes is worse fuel than regular. It resists knock because it's harder to ignite than lower-octane fuels. As a result, some engines won't start as quickly or run as smoothly on premium, notes Gibbs, the SAE fuel expert.
High-test does have a potential fuel economy benefit. It is slightly denser than lower-octane gas, meaning there's a little more energy in a gallon. But the small difference is hard to measure in real-world use, and that same density can contribute to undesirable buildup of waste products inside the engine.
No data show that engines designed strictly for regular run better or longer on premium.
The Federal Trade Commission, in a consumer notice, emphasizes: "(I)n most cases, using a higher-octane gasoline than your owner's manual recommends offers absolutely no benefit. It won't make your car perform better, go faster, get better mileage or run cleaner."
There is "no way of taking advantage of premium in a regular-grade car," says Furey.
"There is no gain. You're wasting money," insists Jim Blenkarn, in charge of powertrains at Nissan in the USA.
"No customer should ever be deluded into thinking there's any value in buying a higher grade of octane than we specify," says Toyota's Paul Williamsen, technical expert and trainer.
But premium retains a mystique.
09-20-2006, 07:43 PM
#73
Registered Member
Originally Posted by pimpin-tl
He is correct to a POINT.
Higher Octane fuels do get a car more power if the car was designed for higher octane fuels like our TL is and the G35 I use to have.
The TL/G35 requires 91+ Octane. Here in Texas we have 87,89,93 octane. So they get 93 octane.
I have seen on my G35 only (never tried it on the TL yet), that when I put 87 octane fuel in the car, it lost a good amount of power (due to the knock sensors pulling timing back). This also has been test proven on a track and dyno. The G35 actually lost 15 hp~ compared to having 93 octane.
But, if you go with anything higher than 91-93 octane you will not notice a difference in power normally.
Higher Octane fuels do get a car more power if the car was designed for higher octane fuels like our TL is and the G35 I use to have.
The TL/G35 requires 91+ Octane. Here in Texas we have 87,89,93 octane. So they get 93 octane.
I have seen on my G35 only (never tried it on the TL yet), that when I put 87 octane fuel in the car, it lost a good amount of power (due to the knock sensors pulling timing back). This also has been test proven on a track and dyno. The G35 actually lost 15 hp~ compared to having 93 octane.
But, if you go with anything higher than 91-93 octane you will not notice a difference in power normally.
Here in my part of Virginia (as I'm sure is the case for the rest of the state and it seems most of the South), we only have 87, 89, and 93 grades available. For a while, Sunoco stations offered 94 octane and I've heard a few still due in my county.
09-20-2006, 07:58 PM
#74
Safety Car
Completely incorrect please read the latest posts here.
Originally Posted by silentsam007
The main advantage of premium-grade gas is that it allows automakers to advertise a few more horsepower by designing and tuning engines to take advantage of premium's anti-knock properties. But auto engineers generally agree that if you use regular in a premium engine, the power loss is so slight, most drivers can't tell.
"I go back and forth, and I'm hard-pressed to notice" whether there's regular or premium in the tank, says Jeff Jetter, principal chemist at Honda Research and Development Americas. He drives an Acura designed for premium.
Import brands, especially, use premium fuel to distinguish their upmarket models. Most Toyotas, for instance, are designed to run on regular or midgrade, while the automaker's Lexus luxury brand prefers premium. Same with Honda and its Acura luxury line.
"Generally, the more expensive the vehicle, the higher the expectation for performance and the more the customer is willing to pay for fuel," says Pete Haidos, head of product planning for Nissan in the USA.
Actually, the price debate is nearly worthless. At 20 cents more for premium, pumping 20 gallons of it instead of regular would cost $4 more. Annually, that's a difference of $171 for a vehicle that averages 14 miles per gallon — as some big sport-utility vehicles do — and is driven 12,000 miles a year.
Gasoline retailers and refiners like high-test because it's more profitable than regular-grade gas is. The retailer paid about 8 cents more for the premium you pay 20 cents more for — though that margin can swing wildly. Refiners make a few cents a gallon more on premium than on regular when they sell to wholesale distributors.
As long as it's clean
Profit is meaningless to the modern engine, which, regardless of what's specified in the owner's manual, hardly cares what you use — as long as it's clean.
Today's engines use highly evolved versions of a device called a knock sensor to adjust settings automatically for low-octane gas. And more engine control computers have adequate memory to allow separate sets of instructions for various octanes. The engine control computers keep pushing to maximize performance on whatever grade of fuel is used.
Extreme pressure inside the cylinders causes knock, which is the sound of the pistons literally rattling inside the cylinders. Too much too long can damage the engine. A little now and then won't.
The only modern engines that should really need premium are those with superchargers, which force-feed fuel into the cylinders. "You're driving along and just tramp the gas and the knock sensor cannot sense the knock fast enough in some cases," because the supercharger boosts pressure so fast, says Bob Furey, chemist and fuels specialist at General Motors.
Burning regular when the owner's manual specifies premium won't void the warranty, nor damage the engine, even the most finicky automakers say. "You're giving up perhaps just a little bit of performance that a customer wouldn't really even notice, it's so slight," says Furey.
Automakers say they don't test premium engines on regular to check the difference, but some auto engineers estimate that power declines roughly 5%.
"We can't guarantee the vehicle will perform as specified if other than premium fuel is used," says Mercedes-Benz spokeswoman Michelle Murad. All U.S. Mercedes engines specify premium.
All Porsche engines are designed for premium, too, but it's not available everywhere. "Our cars must be able to drive all over the world, and so we are able to run on regular," says Jakob Neusser, director of powertrain development at Porsche's research and development center in Weissach, Germany. "You don't have to feel that a mechanical problem or anything else will happen" using regular gas, even in the highest-performance, regular-production Porsches.
Premium, in fact, sometimes is worse fuel than regular. It resists knock because it's harder to ignite than lower-octane fuels. As a result, some engines won't start as quickly or run as smoothly on premium, notes Gibbs, the SAE fuel expert.
High-test does have a potential fuel economy benefit. It is slightly denser than lower-octane gas, meaning there's a little more energy in a gallon. But the small difference is hard to measure in real-world use, and that same density can contribute to undesirable buildup of waste products inside the engine.
No data show that engines designed strictly for regular run better or longer on premium.
The Federal Trade Commission, in a consumer notice, emphasizes: "(I)n most cases, using a higher-octane gasoline than your owner's manual recommends offers absolutely no benefit. It won't make your car perform better, go faster, get better mileage or run cleaner."
There is "no way of taking advantage of premium in a regular-grade car," says Furey.
"There is no gain. You're wasting money," insists Jim Blenkarn, in charge of powertrains at Nissan in the USA.
"No customer should ever be deluded into thinking there's any value in buying a higher grade of octane than we specify," says Toyota's Paul Williamsen, technical expert and trainer.
But premium retains a mystique.
"I go back and forth, and I'm hard-pressed to notice" whether there's regular or premium in the tank, says Jeff Jetter, principal chemist at Honda Research and Development Americas. He drives an Acura designed for premium.
Import brands, especially, use premium fuel to distinguish their upmarket models. Most Toyotas, for instance, are designed to run on regular or midgrade, while the automaker's Lexus luxury brand prefers premium. Same with Honda and its Acura luxury line.
"Generally, the more expensive the vehicle, the higher the expectation for performance and the more the customer is willing to pay for fuel," says Pete Haidos, head of product planning for Nissan in the USA.
Actually, the price debate is nearly worthless. At 20 cents more for premium, pumping 20 gallons of it instead of regular would cost $4 more. Annually, that's a difference of $171 for a vehicle that averages 14 miles per gallon — as some big sport-utility vehicles do — and is driven 12,000 miles a year.
Gasoline retailers and refiners like high-test because it's more profitable than regular-grade gas is. The retailer paid about 8 cents more for the premium you pay 20 cents more for — though that margin can swing wildly. Refiners make a few cents a gallon more on premium than on regular when they sell to wholesale distributors.
As long as it's clean
Profit is meaningless to the modern engine, which, regardless of what's specified in the owner's manual, hardly cares what you use — as long as it's clean.
Today's engines use highly evolved versions of a device called a knock sensor to adjust settings automatically for low-octane gas. And more engine control computers have adequate memory to allow separate sets of instructions for various octanes. The engine control computers keep pushing to maximize performance on whatever grade of fuel is used.
Extreme pressure inside the cylinders causes knock, which is the sound of the pistons literally rattling inside the cylinders. Too much too long can damage the engine. A little now and then won't.
The only modern engines that should really need premium are those with superchargers, which force-feed fuel into the cylinders. "You're driving along and just tramp the gas and the knock sensor cannot sense the knock fast enough in some cases," because the supercharger boosts pressure so fast, says Bob Furey, chemist and fuels specialist at General Motors.
Burning regular when the owner's manual specifies premium won't void the warranty, nor damage the engine, even the most finicky automakers say. "You're giving up perhaps just a little bit of performance that a customer wouldn't really even notice, it's so slight," says Furey.
Automakers say they don't test premium engines on regular to check the difference, but some auto engineers estimate that power declines roughly 5%.
"We can't guarantee the vehicle will perform as specified if other than premium fuel is used," says Mercedes-Benz spokeswoman Michelle Murad. All U.S. Mercedes engines specify premium.
All Porsche engines are designed for premium, too, but it's not available everywhere. "Our cars must be able to drive all over the world, and so we are able to run on regular," says Jakob Neusser, director of powertrain development at Porsche's research and development center in Weissach, Germany. "You don't have to feel that a mechanical problem or anything else will happen" using regular gas, even in the highest-performance, regular-production Porsches.
Premium, in fact, sometimes is worse fuel than regular. It resists knock because it's harder to ignite than lower-octane fuels. As a result, some engines won't start as quickly or run as smoothly on premium, notes Gibbs, the SAE fuel expert.
High-test does have a potential fuel economy benefit. It is slightly denser than lower-octane gas, meaning there's a little more energy in a gallon. But the small difference is hard to measure in real-world use, and that same density can contribute to undesirable buildup of waste products inside the engine.
No data show that engines designed strictly for regular run better or longer on premium.
The Federal Trade Commission, in a consumer notice, emphasizes: "(I)n most cases, using a higher-octane gasoline than your owner's manual recommends offers absolutely no benefit. It won't make your car perform better, go faster, get better mileage or run cleaner."
There is "no way of taking advantage of premium in a regular-grade car," says Furey.
"There is no gain. You're wasting money," insists Jim Blenkarn, in charge of powertrains at Nissan in the USA.
"No customer should ever be deluded into thinking there's any value in buying a higher grade of octane than we specify," says Toyota's Paul Williamsen, technical expert and trainer.
But premium retains a mystique.
09-21-2006, 08:30 PM
#75
That's what I said...
Pimpin-Tl,
No, I am correct. I don't know your background, but I can tell you that from the data and testing that I've done there is NO WAY higher octane fuel makes more power by itself. NO WAY...NO HOW!
What determines power output of ANY gasoline engine is how efficiently it burns fuel. Air is a limiting factor in power output. Higher octane fuels are LESS volitile. I don't care what anybody thinks, this is the truth.
So if you take a brand new Corvette Z06 and pour in 118 octane fuel it WON'T make more horsepower. It just does not work that way.
My 1995 supercharged (8-psi) & intercooled 4.6L T-Bird made 325 RWHP and 380 RWTQ (SAE) on 93 octane Exxon pump gasoline. It was tuned on a dynojet by an ex-Ford engineer and the spark advance was dialed in perfectly.
Here is the Ford engineer tuning a 700 RWHP Mustang GT
Here is my dyno graph from my testing session
Here is the Ford engineer dyno tuning my T-Bird. He is reading HEX code, not some Tuning for Dummies software.
When we tried 100 octane unleaded Sunoco race fuel, guess what? The car made the same amount of power as it did on 93 octane. Not until a few more degrees of spark timing was added did it produce more power.
On the track, I used 100 octane unleaded as an insurance policy and guess what? The car never ran any faster, in fact typically it ran the same e.t. but with less mph.
So then you are in agreement that octane is not what adds power.
A-Train
No, I am correct. I don't know your background, but I can tell you that from the data and testing that I've done there is NO WAY higher octane fuel makes more power by itself. NO WAY...NO HOW!
What determines power output of ANY gasoline engine is how efficiently it burns fuel. Air is a limiting factor in power output. Higher octane fuels are LESS volitile. I don't care what anybody thinks, this is the truth.
So if you take a brand new Corvette Z06 and pour in 118 octane fuel it WON'T make more horsepower. It just does not work that way.
My 1995 supercharged (8-psi) & intercooled 4.6L T-Bird made 325 RWHP and 380 RWTQ (SAE) on 93 octane Exxon pump gasoline. It was tuned on a dynojet by an ex-Ford engineer and the spark advance was dialed in perfectly.
Here is the Ford engineer tuning a 700 RWHP Mustang GT
Here is my dyno graph from my testing session
Here is the Ford engineer dyno tuning my T-Bird. He is reading HEX code, not some Tuning for Dummies software.
When we tried 100 octane unleaded Sunoco race fuel, guess what? The car made the same amount of power as it did on 93 octane. Not until a few more degrees of spark timing was added did it produce more power.
On the track, I used 100 octane unleaded as an insurance policy and guess what? The car never ran any faster, in fact typically it ran the same e.t. but with less mph.
I have seen on my G35 only (never tried it on the TL yet), that when I put 87 octane fuel in the car, it lost a good amount of power (due to the knock sensors pulling timing back). This also has been test proven on a track and dyno. The G35 actually lost 15 hp~ compared to having 93 octane.
A-Train
09-22-2006, 05:21 PM
#76
18,000mi. 29000km
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I am an advocate of 89 for money savings but I gotta tell you when I put 89 in the tank, car pulls slower than 91.
In terms of mileage, if I drive really slow, 87 does not affect mileage at all.
However I like to have fun and hit VTEC on daily basis so I can't live with 87.
In terms of mileage, if I drive really slow, 87 does not affect mileage at all.
However I like to have fun and hit VTEC on daily basis so I can't live with 87.
09-22-2006, 06:30 PM
#77
Safety Car
Testing on what car? Sorry but mustangs are not modern technology. We have tested many cars. Mostly VQ engines in the G35's and have done a lot of testing with 93/87 octanes. Yes the car looses a ton of power on the dyno with 87 octane compared to 93. Car looses over a 1 sec in the 1/4 due to that as well.
There is a different between 87 and 93 octane. HUGE. When you have a high compression engine it is more sensitive to which octane fuels you run in it.
Anything above 93 octane is usless. I agree on that. But I am talking about using 87 instead of 93 in a car that requires 91+.
There is a different between 87 and 93 octane. HUGE. When you have a high compression engine it is more sensitive to which octane fuels you run in it.
Anything above 93 octane is usless. I agree on that. But I am talking about using 87 instead of 93 in a car that requires 91+.
Originally Posted by Atrain
Pimpin-Tl,
No, I am correct. I don't know your background, but I can tell you that from the data and testing that I've done there is NO WAY higher octane fuel makes more power by itself. NO WAY...NO HOW!
What determines power output of ANY gasoline engine is how efficiently it burns fuel. Air is a limiting factor in power output. Higher octane fuels are LESS volitile. I don't care what anybody thinks, this is the truth.
So if you take a brand new Corvette Z06 and pour in 118 octane fuel it WON'T make more horsepower. It just does not work that way.
My 1995 supercharged (8-psi) & intercooled 4.6L T-Bird made 325 RWHP and 380 RWTQ (SAE) on 93 octane Exxon pump gasoline. It was tuned on a dynojet by an ex-Ford engineer and the spark advance was dialed in perfectly.
Here is the Ford engineer tuning a 700 RWHP Mustang GT
Here is my dyno graph from my testing session
Here is the Ford engineer dyno tuning my T-Bird. He is reading HEX code, not some Tuning for Dummies software.
When we tried 100 octane unleaded Sunoco race fuel, guess what? The car made the same amount of power as it did on 93 octane. Not until a few more degrees of spark timing was added did it produce more power.
On the track, I used 100 octane unleaded as an insurance policy and guess what? The car never ran any faster, in fact typically it ran the same e.t. but with less mph.
So then you are in agreement that octane is not what adds power.
A-Train
No, I am correct. I don't know your background, but I can tell you that from the data and testing that I've done there is NO WAY higher octane fuel makes more power by itself. NO WAY...NO HOW!
What determines power output of ANY gasoline engine is how efficiently it burns fuel. Air is a limiting factor in power output. Higher octane fuels are LESS volitile. I don't care what anybody thinks, this is the truth.
So if you take a brand new Corvette Z06 and pour in 118 octane fuel it WON'T make more horsepower. It just does not work that way.
My 1995 supercharged (8-psi) & intercooled 4.6L T-Bird made 325 RWHP and 380 RWTQ (SAE) on 93 octane Exxon pump gasoline. It was tuned on a dynojet by an ex-Ford engineer and the spark advance was dialed in perfectly.
Here is the Ford engineer tuning a 700 RWHP Mustang GT
Here is my dyno graph from my testing session
Here is the Ford engineer dyno tuning my T-Bird. He is reading HEX code, not some Tuning for Dummies software.
When we tried 100 octane unleaded Sunoco race fuel, guess what? The car made the same amount of power as it did on 93 octane. Not until a few more degrees of spark timing was added did it produce more power.
On the track, I used 100 octane unleaded as an insurance policy and guess what? The car never ran any faster, in fact typically it ran the same e.t. but with less mph.
So then you are in agreement that octane is not what adds power.
A-Train
09-23-2006, 08:39 AM
#79
Intermediate
Join Date: Oct 2005
Age: 54
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Is that Jerry? If so he tuned one of my slower Mustangs that made just over 500 rwhp/525 rwtq. He is incredible!
.
.
Originally Posted by Atrain
Pimpin-Tl,
No, I am correct. I don't know your background, but I can tell you that from the data and testing that I've done there is NO WAY higher octane fuel makes more power by itself. NO WAY...NO HOW!
What determines power output of ANY gasoline engine is how efficiently it burns fuel. Air is a limiting factor in power output. Higher octane fuels are LESS volitile. I don't care what anybody thinks, this is the truth.
So if you take a brand new Corvette Z06 and pour in 118 octane fuel it WON'T make more horsepower. It just does not work that way.
My 1995 supercharged (8-psi) & intercooled 4.6L T-Bird made 325 RWHP and 380 RWTQ (SAE) on 93 octane Exxon pump gasoline. It was tuned on a dynojet by an ex-Ford engineer and the spark advance was dialed in perfectly.
Here is the Ford engineer tuning a 700 RWHP Mustang GT
Here is my dyno graph from my testing session
Here is the Ford engineer dyno tuning my T-Bird. He is reading HEX code, not some Tuning for Dummies software.
When we tried 100 octane unleaded Sunoco race fuel, guess what? The car made the same amount of power as it did on 93 octane. Not until a few more degrees of spark timing was added did it produce more power.
On the track, I used 100 octane unleaded as an insurance policy and guess what? The car never ran any faster, in fact typically it ran the same e.t. but with less mph.
So then you are in agreement that octane is not what adds power.
A-Train
No, I am correct. I don't know your background, but I can tell you that from the data and testing that I've done there is NO WAY higher octane fuel makes more power by itself. NO WAY...NO HOW!
What determines power output of ANY gasoline engine is how efficiently it burns fuel. Air is a limiting factor in power output. Higher octane fuels are LESS volitile. I don't care what anybody thinks, this is the truth.
So if you take a brand new Corvette Z06 and pour in 118 octane fuel it WON'T make more horsepower. It just does not work that way.
My 1995 supercharged (8-psi) & intercooled 4.6L T-Bird made 325 RWHP and 380 RWTQ (SAE) on 93 octane Exxon pump gasoline. It was tuned on a dynojet by an ex-Ford engineer and the spark advance was dialed in perfectly.
Here is the Ford engineer tuning a 700 RWHP Mustang GT
Here is my dyno graph from my testing session
Here is the Ford engineer dyno tuning my T-Bird. He is reading HEX code, not some Tuning for Dummies software.
When we tried 100 octane unleaded Sunoco race fuel, guess what? The car made the same amount of power as it did on 93 octane. Not until a few more degrees of spark timing was added did it produce more power.
On the track, I used 100 octane unleaded as an insurance policy and guess what? The car never ran any faster, in fact typically it ran the same e.t. but with less mph.
So then you are in agreement that octane is not what adds power.
A-Train
09-23-2006, 02:27 PM
#80
18,000mi. 29000km
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In the end of the day, this debate comes down to:
87 vs 91
- Less fun due to less pulling power
- Same mileage if you can be a granma driver, otherwise mileage will be worse because you will have to gas more to keep the car moving.
91 vs 93+
-no visible or memorable advantage
-costs more
I personally go back and forth between 89 and 91. My options are 87/89/91 at local stations.
87 vs 91
- Less fun due to less pulling power
- Same mileage if you can be a granma driver, otherwise mileage will be worse because you will have to gas more to keep the car moving.
91 vs 93+
-no visible or memorable advantage
-costs more
I personally go back and forth between 89 and 91. My options are 87/89/91 at local stations.