Regular 87 Octane and Intro
#31
04-26-2005, 06:11 PM
Each time youi USE that performance, you LOSE the mileage gain advantage![/QUOTE]
The point isn't that you are running your car WOT at the redline all day everyday. Under normal driving conditions it will work out to be about a wash. If you turn it up a little, you are going to lose mileage at around the same rate whether you are running 91 or 87 so everytime you open it up, like I said, "to take advantage of the performance", you would be losing it on the 87 too. So it is a wash.
At the end of the day we are talking about maybe 3 bucks a fill. Instead of buying a red bull and a candy bar that are just going to make you fat anyways, put the 3 bucks into the tank. I see it as an even cost:benefit ratio so I just do it. the cost is 3 bucks and the associated benefit for me works out to be at least 3 bucks, so it is a no brainer.
And if it is .20 a gallon to upgrade you guys need to find a different fillup station. Here in MN most places it is .10 except for BP and Shell (crazy prices). We even have 1 place that is .07 cents to go from regular to premium, midgrade 89 is the same price as 87. Works out good for me. And for me, that means it is like 1 dollar, easily justifiable.
The point isn't that you are running your car WOT at the redline all day everyday. Under normal driving conditions it will work out to be about a wash. If you turn it up a little, you are going to lose mileage at around the same rate whether you are running 91 or 87 so everytime you open it up, like I said, "to take advantage of the performance", you would be losing it on the 87 too. So it is a wash.
At the end of the day we are talking about maybe 3 bucks a fill. Instead of buying a red bull and a candy bar that are just going to make you fat anyways, put the 3 bucks into the tank. I see it as an even cost:benefit ratio so I just do it. the cost is 3 bucks and the associated benefit for me works out to be at least 3 bucks, so it is a no brainer.
And if it is .20 a gallon to upgrade you guys need to find a different fillup station. Here in MN most places it is .10 except for BP and Shell (crazy prices). We even have 1 place that is .07 cents to go from regular to premium, midgrade 89 is the same price as 87. Works out good for me. And for me, that means it is like 1 dollar, easily justifiable.
#32
04-26-2005, 09:51 PM
Originally Posted by PotomacG
Predetonation will do nothing to the top of your piston. Severe pinging might cause your connecting rod to detach and possibly put a sizeable hole in your cylinder head.
It's common knowledge amongst those with experience and knowledge that damage to pistons can result from predetonation.
I have both seen and done it.
#33
04-26-2005, 10:08 PM
Originally Posted by RJP6
Why wouldn't the octane level be the same number in all manuals?
http://www.infiniti.com/m/pdf/manual...finiti-G35.pdf
#34
04-26-2005, 10:33 PM
FUEL RECOMMENDATION
Sedan models
Use unleaded regular gasoline with an octane rating of at least 87 AKI (Anti-Knock Index) number (Research octane number 91). For improved vehicle performance, INFINITI recommends the use of unleaded premium gasoline with an octane rating of at least 91 AKI number (Research octane number 96).
Coupe models
Use unleaded premium gasoline with an octane rating of at least 91 AKI (Anti-Knock Index) number (Research octane number 96). If premium gasoline is not available, unleaded regular gasoline with an octane rating of 87 AKI number (Research octane number 91) may be temporarily used, but only under the following precautions:
Have the fuel tank filled only partially with unleaded regular gasoline, and fill up with unleaded premium gasoline as soon as possible.
Avoid full throttle driving and abrupt acceleration. However, for maximum vehicle performance, the use of unleaded premium gasoline is recommended.
CAUTION
Using a fuel other than that specified could adversely affect the emission control devices and systems, and could also affect the warranty coverage. Under no circumstances should a leaded gasoline be used, since this will damage the three-way catalyst.
INFINITI does not recommend the use of any aftermarket fuel additives (i.e. fuel injector cleaner, octane booster, intake valve deposit removers, etc.) which are sold commercially. Many of these additives intended for gum, varnish or deposit removal may contain active solvent or similar ingredients that can be harmful to the fuel system and engine.
Octane rating tips
In most parts of North America, you should use unleaded gasoline with an octane rating of at least 87 or 91 AKI (Anti-Knock Index) number. However, you may use unleaded gasoline with an octane rating as low as 85 AKI number in these high altitude areas [over 4,000 ft (1,219m)] such as: Colorado, Montana, New Mexico, Utah, Wyoming, northeastern Nevada, southern Idaho, western South Dakota, western Nebraska, and that part of Texas which is directly south of New Mexico.
Using unleaded gasoline with an octane rating lower than stated above can cause persistent, heavy spark knock. (Spark knock is a metallic rapping noise.) If severe, this can lead to engine damage. If you detect a persistent heavy spark knock even when using gasoline of the stated octane rating, or if you hear steady spark knock while holding a steady speed on level roads, have your dealer correct the condition. Failure to correct the condition is misuse of the vehicle, for which INFINITI is not responsible. Incorrect ignition timing will result in knocking, after-run or overheating. This in turn may cause excessive fuel consumption or damage to the engine. If any of the above symptoms are encountered, have your vehicle checked at an INFINITI dealer or other competent service facility. However, now and then you may notice light spark knock for a short time while accelerating or driving up hills. This is no cause for concern, because you get the greatest fuel benefit when there is light spark knock for a short time under heavy engine load.
Right out of the manual
Sedan models
Use unleaded regular gasoline with an octane rating of at least 87 AKI (Anti-Knock Index) number (Research octane number 91). For improved vehicle performance, INFINITI recommends the use of unleaded premium gasoline with an octane rating of at least 91 AKI number (Research octane number 96).
Coupe models
Use unleaded premium gasoline with an octane rating of at least 91 AKI (Anti-Knock Index) number (Research octane number 96). If premium gasoline is not available, unleaded regular gasoline with an octane rating of 87 AKI number (Research octane number 91) may be temporarily used, but only under the following precautions:
Have the fuel tank filled only partially with unleaded regular gasoline, and fill up with unleaded premium gasoline as soon as possible.
Avoid full throttle driving and abrupt acceleration. However, for maximum vehicle performance, the use of unleaded premium gasoline is recommended.
CAUTION
Using a fuel other than that specified could adversely affect the emission control devices and systems, and could also affect the warranty coverage. Under no circumstances should a leaded gasoline be used, since this will damage the three-way catalyst.
INFINITI does not recommend the use of any aftermarket fuel additives (i.e. fuel injector cleaner, octane booster, intake valve deposit removers, etc.) which are sold commercially. Many of these additives intended for gum, varnish or deposit removal may contain active solvent or similar ingredients that can be harmful to the fuel system and engine.
Octane rating tips
In most parts of North America, you should use unleaded gasoline with an octane rating of at least 87 or 91 AKI (Anti-Knock Index) number. However, you may use unleaded gasoline with an octane rating as low as 85 AKI number in these high altitude areas [over 4,000 ft (1,219m)] such as: Colorado, Montana, New Mexico, Utah, Wyoming, northeastern Nevada, southern Idaho, western South Dakota, western Nebraska, and that part of Texas which is directly south of New Mexico.
Using unleaded gasoline with an octane rating lower than stated above can cause persistent, heavy spark knock. (Spark knock is a metallic rapping noise.) If severe, this can lead to engine damage. If you detect a persistent heavy spark knock even when using gasoline of the stated octane rating, or if you hear steady spark knock while holding a steady speed on level roads, have your dealer correct the condition. Failure to correct the condition is misuse of the vehicle, for which INFINITI is not responsible. Incorrect ignition timing will result in knocking, after-run or overheating. This in turn may cause excessive fuel consumption or damage to the engine. If any of the above symptoms are encountered, have your vehicle checked at an INFINITI dealer or other competent service facility. However, now and then you may notice light spark knock for a short time while accelerating or driving up hills. This is no cause for concern, because you get the greatest fuel benefit when there is light spark knock for a short time under heavy engine load.
Right out of the manual
Last edited by ashadiow; 04-26-2005 at 10:44 PM.
#35
04-26-2005, 10:40 PM
#36
04-26-2005, 10:48 PM
#37
04-27-2005, 07:46 AM
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The funniest thing is that some people have to pick up the Dunkins every morning for 2 bucks while they serve free coffee at work. They like the taste of 5 cups of coffee for 10 bucks a week. I said to someone who was complaing about the gas prices to stop getting coffee a couple of days a week and buy the 93 octane for your 35,000 car.
Yes I do believe the knock sensors will take care of the car. But, do I want to rely on that component all the time. In the past if you had above 10:1 compression ratio it meant that you should using gas that has a higher ocatane rating than regular. I had a oldsmobile rocket V8 that got a hole the size of a dime in one of the pistons because someone put regular gas in it. So given that experience I find that do I want to rely on that knock sensor... I have an acura as well with 11:1 compression while the vq is 10.3:1. Some people have complained that their knock senor wire was chewed by mice. So if that means that it does not work properly would I want to have 87 octane in that car... go figure...
Yes I do believe the knock sensors will take care of the car. But, do I want to rely on that component all the time. In the past if you had above 10:1 compression ratio it meant that you should using gas that has a higher ocatane rating than regular. I had a oldsmobile rocket V8 that got a hole the size of a dime in one of the pistons because someone put regular gas in it. So given that experience I find that do I want to rely on that knock sensor... I have an acura as well with 11:1 compression while the vq is 10.3:1. Some people have complained that their knock senor wire was chewed by mice. So if that means that it does not work properly would I want to have 87 octane in that car... go figure...
#38
04-27-2005, 08:33 AM
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Originally Posted by SAL9000
So you're saying that unsinc'd combustion powerful enough to knock a rod off isn't strong enough to damage the top of a piston??? Come on.
It's common knowledge amongst those with experience and knowledge that damage to pistons can result from predetonation.
I have both seen and done it.
It's common knowledge amongst those with experience and knowledge that damage to pistons can result from predetonation.
I have both seen and done it.
#39
04-27-2005, 09:32 AM
Originally Posted by PotomacG
Is it unsnc'd or asynchrounous? Yes you are absouletly correct. When you throw a connectung rod, you are, by definition, damaging the hell out of your piston. OK? Are you happy now?
Amongst other things, predetonation can damage the tops of pistons (rods throwing vis-a-vis predetonation is an ENTIRELY different phenomenon). Does it happen in a day? Not anymore, at least with most modern cars. Again, have both seen, done, and had to repair engines because of it (old school domestic V8s). I suggest doing some research on it. There's lots of info out there. You'll feel like a smarty pants, too
. Sorry, but there's no argument here. Predetonation, as it is trying to knock holes in the tops of pistons, is also excessively loading up the rod bearing, which can lead to a spun bearing, and if left unchecked, can cause the rod to disconnect from the crank. This can damage a piston, but by entirely different means. This problem becomes much more amplified when the engine is lugging, as in a manual transmission (or no anti-lugging device, i.e., torque converter), because of the lower oil pressure at lower RPMs, and why it is that more imperative to follow the mfr's octane requirments.
Go forward in the world and rule with your new-found knowledge!
#40
04-27-2005, 10:04 AM
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Originally Posted by SAL9000
Almost happy...
Amongst other things, predetonation can damage the tops of pistons (rods throwing vis-a-vis predetonation is an ENTIRELY different phenomenon). Does it happen in a day? Not anymore, at least with most modern cars. Again, have both seen, done, and had to repair engines because of it (old school domestic V8s). I suggest doing some research on it. There's lots of info out there. You'll feel like a smarty pants, too. Sorry, but there's no argument here.
Predetonation, as it is trying to knock holes in the tops of pistons, is also excessively loading up the rod bearing, which can lead to a spun bearing, and if left unchecked, can cause the rod to disconnect from the crank. This can damage a piston, but by entirely different means. This problem becomes much more amplified when the engine is lugging, as in a manual transmission (or no anti-lugging device, i.e., torque converter), because of the lower oil pressure at lower RPMs, and why it is that more imperative to follow the mfr's octane requirments.
Go forward in the world and rule with your new-found knowledge!
Amongst other things, predetonation can damage the tops of pistons (rods throwing vis-a-vis predetonation is an ENTIRELY different phenomenon). Does it happen in a day? Not anymore, at least with most modern cars. Again, have both seen, done, and had to repair engines because of it (old school domestic V8s). I suggest doing some research on it. There's lots of info out there. You'll feel like a smarty pants, too
. Sorry, but there's no argument here. Predetonation, as it is trying to knock holes in the tops of pistons, is also excessively loading up the rod bearing, which can lead to a spun bearing, and if left unchecked, can cause the rod to disconnect from the crank. This can damage a piston, but by entirely different means. This problem becomes much more amplified when the engine is lugging, as in a manual transmission (or no anti-lugging device, i.e., torque converter), because of the lower oil pressure at lower RPMs, and why it is that more imperative to follow the mfr's octane requirments.
Go forward in the world and rule with your new-found knowledge!
#41
04-28-2005, 08:47 PM
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Originally Posted by kevink
FWIW, word is that all 2005s require 91 octane. The extra HP out of the engine for 2005.
I can speak for my old Altima 3.5 with the same basic VQ35 engine. The Nissan Owner's Manual had the identical split 87-is-fine-but-91-is-recommended-for-best-performance line. So I ran 87 octane a few times here and there. The car was uniformly sluggish compared with the local 93 octane brew, so I pretty much stuck to Nissan's recommendation and went with the expensive stuff. If I owned an '05 5AT, I'd do the same.
The rest of the debate regarding fuel mileage versus octane has no legs. You'll get the same mileage with 87, 89, 91 or 93 octane. There are hundreds of variable that contribute to uneven gas mileage between tanks. Octane is not one of them.
#42
04-29-2005, 08:59 AM
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Nice!
#44
04-29-2005, 10:45 AM
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You know, this is one of those threads that will just go around in circles. Some will stick with 87 and some will swear by 91 or better. Then there are those in the middle that combine octanes. But my question is for those car fanatics that believe that if you spend 30K on a car, then you must use the best gas. So if you believe that, then you should own a $500,000 home or better (no apartment!), have a garage, park the car in the garage, cover the car when outside, park at the far end of the parking lot, wash the car weekly, wax and detail every couple of months, spend 3 days detailing your car, etc. If you don't then you too should not have a 30K car.
What I am getting at is that everyone is entitled to their own opinions, and that is great. That is what this forum is about. There is a lot of useful info here. But there is absolutely no correlation between the cost of a car and the fuel.
Some of you are fortunate to have lower gas prices, but here in cali, we have the highest prices around. And not just for gas, but for homes and the general cost of living. And don't forget that sunshine tax that we pay. So I can understand that someone wants to save a little money. Take that extra $100 - $200 dollars a year and take the family out to dinner!
Anyways, just venting a little on a friday. I'm sure that if we combine all of the octane threads on this forum it will be as large as the uncomfortable drivers seat thread! Everyone spend your money the way you want. Use this forum and your manual to make an informed decision. Have a great weekend everyone!@
What I am getting at is that everyone is entitled to their own opinions, and that is great. That is what this forum is about. There is a lot of useful info here. But there is absolutely no correlation between the cost of a car and the fuel.
Some of you are fortunate to have lower gas prices, but here in cali, we have the highest prices around. And not just for gas, but for homes and the general cost of living. And don't forget that sunshine tax that we pay. So I can understand that someone wants to save a little money. Take that extra $100 - $200 dollars a year and take the family out to dinner!
Anyways, just venting a little on a friday. I'm sure that if we combine all of the octane threads on this forum it will be as large as the uncomfortable drivers seat thread! Everyone spend your money the way you want. Use this forum and your manual to make an informed decision. Have a great weekend everyone!@
#45
04-29-2005, 10:52 AM
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Originally Posted by Eticketride
You know, this is one of those threads that will just go around in circles. Some will stick with 87 and some will swear by 91 or better. Then there are those in the middle that combine octanes. But my question is for those car fanatics that believe that if you spend 30K on a car, then you must use the best gas. So if you believe that, then you should own a $500,000 home or better (no apartment!), have a garage, park the car in the garage, cover the car when outside, park at the far end of the parking lot, wash the car weekly, wax and detail every couple of months, spend 3 days detailing your car, etc. If you don't then you too should not have a 30K car.
What I am getting at is that everyone is entitled to their own opinions, and that is great. That is what this forum is about. There is a lot of useful info here. But there is absolutely no correlation between the cost of a car and the fuel.
Some of you are fortunate to have lower gas prices, but here in cali, we have the highest prices around. And not just for gas, but for homes and the general cost of living. And don't forget that sunshine tax that we pay. So I can understand that someone wants to save a little money. Take that extra $100 - $200 dollars a year and take the family out to dinner!
Anyways, just venting a little on a friday. I'm sure that if we combine all of the octane threads on this forum it will be as large as the uncomfortable drivers seat thread! Everyone spend your money the way you want. Use this forum and your manual to make an informed decision. Have a great weekend everyone!@
What I am getting at is that everyone is entitled to their own opinions, and that is great. That is what this forum is about. There is a lot of useful info here. But there is absolutely no correlation between the cost of a car and the fuel.
Some of you are fortunate to have lower gas prices, but here in cali, we have the highest prices around. And not just for gas, but for homes and the general cost of living. And don't forget that sunshine tax that we pay. So I can understand that someone wants to save a little money. Take that extra $100 - $200 dollars a year and take the family out to dinner!
Anyways, just venting a little on a friday. I'm sure that if we combine all of the octane threads on this forum it will be as large as the uncomfortable drivers seat thread! Everyone spend your money the way you want. Use this forum and your manual to make an informed decision. Have a great weekend everyone!@