87 & 91 octane?
09-20-2006, 12:22 PM
#26
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Originally Posted by LandonElf
On a supercharged car, the powerband is so smooth that sometimes its hard to recognize an acceleration difference. But when even the friggan manual says that your losing power, your losing power. And there refering to a bone stock ss/sc!!
Imagine the potential lost in a staged vehicle or even one with just bolt-ons? This shouldn't really be an argument. If you can afford a $20000+ performance vehicle, you can afford to put the top notch stuff in it. Dont ruin your cars potential and the cobalts reputation just to save a 1 dollar.
Imagine the potential lost in a staged vehicle or even one with just bolt-ons? This shouldn't really be an argument. If you can afford a $20000+ performance vehicle, you can afford to put the top notch stuff in it. Dont ruin your cars potential and the cobalts reputation just to save a 1 dollar.
for those trying to save money you would be better off cutting back at least one day each month on fast food,
87 octane 12x2.6=31.2 per fill
91 octane 12x2.8=33.6 per fil
(I know the gas tank is larger than 12 gallons but you likely never get down to 1 gallon left unless you like to live on the edge of stupidity by choking your car)
09-20-2006, 01:36 PM
#29
I'm going to play devil's advocate here...
I run 87 in my SS/SC EVERY time. I've had 93 in it before and felt NO difference in power for regualr street driving. I have not had a single ping or knock, ever.
This says 2 things...one, I don't beat my car hard enough to see the difference. This also means that I don't beat my car hard enough to utilize a higher octane fuel.
Rember, using an octane that is higher than needed will actually cause the engine to get DIRTIER and cause more carbon deposits on the valves and combustion chambers.
If I notice ping, I step up the ocatne. If not, then I'm not hurting anything, and possibly helping it.
By this same argument, I would NOT recommend running 94 in a stock SS/SC unless you live in a retardedly hot climate. Again, it's more octane than you need which is going to cause more deposits in the motor and not see any performance gain.
Higher octane is not better quality. Higher octane merely means it burns slower...the quality is all the same, so if your car runs fine on 87, then buy friggin' 87. I know that gas stations around here gouge the **** out of the premium gas in order to try and keep the regular prices lower. You all are saying there's 20 cent different between 87 and 91/92, which is usually correct, but around here that difference can be as high as 50 cents a gallon.
However, seeing that as many of you have said you've noticed performance losses when filling up with regular vs. premium, I may try it out. Someone said it takes half a tank for the computer to get used to the new grade of gasoline, so maybe the cars ran really bad because the computer was still using the curve for the premium fuel. Perhaps that's why mine has seemed fine from day one, because it's always gotten 87. It will be an interesting experiment.
EDIT: And the manual says that 91 is recomended, but 87 can be used unless you experience pinging. I can't see the manual telling you it's okay to do something that would cause detonation in the engine...that's kind of a big deal...
I run 87 in my SS/SC EVERY time. I've had 93 in it before and felt NO difference in power for regualr street driving. I have not had a single ping or knock, ever.
This says 2 things...one, I don't beat my car hard enough to see the difference. This also means that I don't beat my car hard enough to utilize a higher octane fuel.
Rember, using an octane that is higher than needed will actually cause the engine to get DIRTIER and cause more carbon deposits on the valves and combustion chambers.
If I notice ping, I step up the ocatne. If not, then I'm not hurting anything, and possibly helping it.
By this same argument, I would NOT recommend running 94 in a stock SS/SC unless you live in a retardedly hot climate. Again, it's more octane than you need which is going to cause more deposits in the motor and not see any performance gain.
Higher octane is not better quality. Higher octane merely means it burns slower...the quality is all the same, so if your car runs fine on 87, then buy friggin' 87. I know that gas stations around here gouge the **** out of the premium gas in order to try and keep the regular prices lower. You all are saying there's 20 cent different between 87 and 91/92, which is usually correct, but around here that difference can be as high as 50 cents a gallon.
However, seeing that as many of you have said you've noticed performance losses when filling up with regular vs. premium, I may try it out. Someone said it takes half a tank for the computer to get used to the new grade of gasoline, so maybe the cars ran really bad because the computer was still using the curve for the premium fuel. Perhaps that's why mine has seemed fine from day one, because it's always gotten 87. It will be an interesting experiment.
EDIT: And the manual says that 91 is recomended, but 87 can be used unless you experience pinging. I can't see the manual telling you it's okay to do something that would cause detonation in the engine...that's kind of a big deal...
09-20-2006, 01:57 PM
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Does this 87 vs 91 discussion also pertain to the 2.4L, or is everyone talking about the 2.0L
SC? The 2.2 has 10:1 compression and the 2.4 has 10.4:1. I guess that difference is why the 2.4L is recommended to have 91? Other engines have VVT and don't requrie 91, so it must be the compression ratio. My only concern with using 91 is how do you know you're really getting it? What's to stop the station from putting 87 in all their tanks and just making extra money by pretending to sell you 91? I want to get an SS sedan; that's why I chimed in.
SC? The 2.2 has 10:1 compression and the 2.4 has 10.4:1. I guess that difference is why the 2.4L is recommended to have 91? Other engines have VVT and don't requrie 91, so it must be the compression ratio. My only concern with using 91 is how do you know you're really getting it? What's to stop the station from putting 87 in all their tanks and just making extra money by pretending to sell you 91? I want to get an SS sedan; that's why I chimed in.
09-20-2006, 04:26 PM
#31
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Originally Posted by xl1200r
I'm going to play devil's advocate here...
I run 87 in my SS/SC EVERY time. I've had 93 in it before and felt NO difference in power for regualr street driving. I have not had a single ping or knock, ever.
This says 2 things...one, I don't beat my car hard enough to see the difference. This also means that I don't beat my car hard enough to utilize a higher octane fuel.
Rember, using an octane that is higher than needed will actually cause the engine to get DIRTIER and cause more carbon deposits on the valves and combustion chambers.
If I notice ping, I step up the ocatne. If not, then I'm not hurting anything, and possibly helping it.
By this same argument, I would NOT recommend running 94 in a stock SS/SC unless you live in a retardedly hot climate. Again, it's more octane than you need which is going to cause more deposits in the motor and not see any performance gain.
Higher octane is not better quality. Higher octane merely means it burns slower...the quality is all the same, so if your car runs fine on 87, then buy friggin' 87. I know that gas stations around here gouge the **** out of the premium gas in order to try and keep the regular prices lower. You all are saying there's 20 cent different between 87 and 91/92, which is usually correct, but around here that difference can be as high as 50 cents a gallon.
However, seeing that as many of you have said you've noticed performance losses when filling up with regular vs. premium, I may try it out. Someone said it takes half a tank for the computer to get used to the new grade of gasoline, so maybe the cars ran really bad because the computer was still using the curve for the premium fuel. Perhaps that's why mine has seemed fine from day one, because it's always gotten 87. It will be an interesting experiment.
EDIT: And the manual says that 91 is recomended, but 87 can be used unless you experience pinging. I can't see the manual telling you it's okay to do something that would cause detonation in the engine...that's kind of a big deal...
I run 87 in my SS/SC EVERY time. I've had 93 in it before and felt NO difference in power for regualr street driving. I have not had a single ping or knock, ever.
This says 2 things...one, I don't beat my car hard enough to see the difference. This also means that I don't beat my car hard enough to utilize a higher octane fuel.
Rember, using an octane that is higher than needed will actually cause the engine to get DIRTIER and cause more carbon deposits on the valves and combustion chambers.
If I notice ping, I step up the ocatne. If not, then I'm not hurting anything, and possibly helping it.
By this same argument, I would NOT recommend running 94 in a stock SS/SC unless you live in a retardedly hot climate. Again, it's more octane than you need which is going to cause more deposits in the motor and not see any performance gain.
Higher octane is not better quality. Higher octane merely means it burns slower...the quality is all the same, so if your car runs fine on 87, then buy friggin' 87. I know that gas stations around here gouge the **** out of the premium gas in order to try and keep the regular prices lower. You all are saying there's 20 cent different between 87 and 91/92, which is usually correct, but around here that difference can be as high as 50 cents a gallon.
However, seeing that as many of you have said you've noticed performance losses when filling up with regular vs. premium, I may try it out. Someone said it takes half a tank for the computer to get used to the new grade of gasoline, so maybe the cars ran really bad because the computer was still using the curve for the premium fuel. Perhaps that's why mine has seemed fine from day one, because it's always gotten 87. It will be an interesting experiment.
EDIT: And the manual says that 91 is recomended, but 87 can be used unless you experience pinging. I can't see the manual telling you it's okay to do something that would cause detonation in the engine...that's kind of a big deal...
You may not pull alot, and you may not even pull any once or twice, but if you run it alot, you're losing timing. Staged there's no question, if I add one degree of timing to the stage tune with Shell 93 octane, I will get random knock starting. Usually no more than 1* or so, but it starts.
I'm not sure where people get this 1/2 tank of gas idea from, the car is constantly trying to use the high octane map, and the weighted average seems to adjust almost instantly. For instance, when I use my 100 octane tune at the track, it's instantly adjusted... now, if you were knocking like hell and driving it with 87 for hours, it's possible for you to weight the average so much that it might take 10-15 min to go back the other way... Also, if you're not flooring it, you're not forcing it to use the low octane tables at all.
09-20-2006, 05:28 PM
#33
Originally Posted by xl1200r
I'm going to play devil's advocate here...
I run 87 in my SS/SC EVERY time. I've had 93 in it before and felt NO difference in power for regualr street driving. I have not had a single ping or knock, ever.
This says 2 things...one, I don't beat my car hard enough to see the difference. This also means that I don't beat my car hard enough to utilize a higher octane fuel.
Rember, using an octane that is higher than needed will actually cause the engine to get DIRTIER and cause more carbon deposits on the valves and combustion chambers.
If I notice ping, I step up the ocatne. If not, then I'm not hurting anything, and possibly helping it.
By this same argument, I would NOT recommend running 94 in a stock SS/SC unless you live in a retardedly hot climate. Again, it's more octane than you need which is going to cause more deposits in the motor and not see any performance gain.
Higher octane is not better quality. Higher octane merely means it burns slower...the quality is all the same, so if your car runs fine on 87, then buy friggin' 87. I know that gas stations around here gouge the **** out of the premium gas in order to try and keep the regular prices lower. You all are saying there's 20 cent different between 87 and 91/92, which is usually correct, but around here that difference can be as high as 50 cents a gallon.
However, seeing that as many of you have said you've noticed performance losses when filling up with regular vs. premium, I may try it out. Someone said it takes half a tank for the computer to get used to the new grade of gasoline, so maybe the cars ran really bad because the computer was still using the curve for the premium fuel. Perhaps that's why mine has seemed fine from day one, because it's always gotten 87. It will be an interesting experiment.
EDIT: And the manual says that 91 is recomended, but 87 can be used unless you experience pinging. I can't see the manual telling you it's okay to do something that would cause detonation in the engine...that's kind of a big deal...
I run 87 in my SS/SC EVERY time. I've had 93 in it before and felt NO difference in power for regualr street driving. I have not had a single ping or knock, ever.
This says 2 things...one, I don't beat my car hard enough to see the difference. This also means that I don't beat my car hard enough to utilize a higher octane fuel.
Rember, using an octane that is higher than needed will actually cause the engine to get DIRTIER and cause more carbon deposits on the valves and combustion chambers.
If I notice ping, I step up the ocatne. If not, then I'm not hurting anything, and possibly helping it.
By this same argument, I would NOT recommend running 94 in a stock SS/SC unless you live in a retardedly hot climate. Again, it's more octane than you need which is going to cause more deposits in the motor and not see any performance gain.
Higher octane is not better quality. Higher octane merely means it burns slower...the quality is all the same, so if your car runs fine on 87, then buy friggin' 87. I know that gas stations around here gouge the **** out of the premium gas in order to try and keep the regular prices lower. You all are saying there's 20 cent different between 87 and 91/92, which is usually correct, but around here that difference can be as high as 50 cents a gallon.
However, seeing that as many of you have said you've noticed performance losses when filling up with regular vs. premium, I may try it out. Someone said it takes half a tank for the computer to get used to the new grade of gasoline, so maybe the cars ran really bad because the computer was still using the curve for the premium fuel. Perhaps that's why mine has seemed fine from day one, because it's always gotten 87. It will be an interesting experiment.
EDIT: And the manual says that 91 is recomended, but 87 can be used unless you experience pinging. I can't see the manual telling you it's okay to do something that would cause detonation in the engine...that's kind of a big deal...
Whats your owners manual say? Does it say 87 is ok?
Anyway you won't hear it pinging cause the computer is pulling timing out so it won't. Timing that fires the plugs late reduces knocks and pings BUT increases carbon deposits and emmisions. Your right about high octain in a car that does not need it, yours does so your actualy putting more carbon in and harming your engine in the long run to save a few bucks at the pump.
Don't be cheep, put the grade of fuel your car requires in it. If you can't afford the fuel you shouldn't have bought the car.
Its the same as wanting to put the $25.00 Pep Boys special tires on your car. Stop being cheap!
DISCLAIMER::::: THIS WAS NOT INTENDED TO ANY SINGLE INDIVIDUAL AT ALL. RATHER ANYONE WHO THINKS THAT CHEAP GAS IS OK.
09-20-2006, 06:03 PM
#34
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Is it possible the car will burn the fuel quicker with higher octane gas? I have heard some cars do and I think my cobalt did, it was near half tank 70-90kms faster than normal. Was this just a freak occurance or is there more to it? thanks
09-20-2006, 06:38 PM
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the car has a low and normal octane trim and adjusts accordingly to keep the car from being damaged when using the wrong grade. you are getting far worse gas mileage than someone running the optimal fuel rate so in reality you are spending less more often than spending more less often.
seriously ~2 bucks a fill is nothing when you get better performance and fuel economy in return. Like I said don't go buy fast food ONE day out of the month and you will have already paid for your car to run at optimal gas levels for that month
seriously ~2 bucks a fill is nothing when you get better performance and fuel economy in return. Like I said don't go buy fast food ONE day out of the month and you will have already paid for your car to run at optimal gas levels for that month
09-20-2006, 07:49 PM
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Originally Posted by R&C_rallySS
I run 93 all the time. The first tank from the dealer was crappy 87. The car knocked like hell and I told them off about it. Ended up getting a free tank of gas and oil change. In the book the SS/SC calls for at least 91. It also says you can run 89 but you could hear knocking. Basicly the higher octane you run the smoother and cleaner your engine will burn. In the long run your engine will last much longer with a good quilty mid-high grade octane. Now that I run 93 all the time I notice much smoother driving and performance increase.
I had the same issue when i picked up my car. The stupid sales lady filled it with 87 and it pinged all the way home. I had to really baby the thing till i could get a full tank of 93
09-20-2006, 07:57 PM
#38
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heyy guys i have an ss/sc and i always put in 91 should i move up to 94 or is 91 fine?? and i noticed esso wasn't on that list can someone let me know of some of the good gas places in canada?? thnks alot
09-20-2006, 08:00 PM
#39
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maybe...just maybe thats why my chicks car just doesnt feel quick at all. i've only opened it up just a few times, but it seems like a dog. i expected more for a sc cobalt that everyone says is almost as fast as a 350z. going to get 93 tonight. it's gonna need all the help it can get when i put it up against my 350 saturday. haha
09-20-2006, 08:25 PM
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Originally Posted by OmaCobaltss
Since gas has gone down I just put in 92 as opposed to 89. daily driven and punched it a few times. I have SS/NA and auto and I cannot feel any difference in performance. However, I'll bet it may be different for SS/SC if that's what you're going to get.
if the car does not knock with 87, you won't notice any performance gain with a higher octane. There is no way for the car to tell what octane you put in, so the only reason you would see more performance is if you were knocking on 87, so in a way, you really dont GAIN performance with higher octane, you are LOSING performance with too low of an octane if that is happening at all.
09-20-2006, 08:26 PM
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Originally Posted by Blububble
maybe...just maybe thats why my chicks car just doesnt feel quick at all. i've only opened it up just a few times, but it seems like a dog. i expected more for a sc cobalt that everyone says is almost as fast as a 350z. going to get 93 tonight. it's gonna need all the help it can get when i put it up against my 350 saturday. haha
well all things considered, with equal drivers, the z is a faster car...
09-21-2006, 12:34 AM
#43
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Originally Posted by 8cd03gro
if the car does not knock with 87, you won't notice any performance gain with a higher octane. There is no way for the car to tell what octane you put in, so the only reason you would see more performance is if you were knocking on 87, so in a way, you really dont GAIN performance with higher octane, you are LOSING performance with too low of an octane if that is happening at all.
Run Premium, your car can run leaner mixtures, the fuel is less suseptible to detonation, and all thigsn previously mentioned about deposits. If you have a Forced Induction car always run at least 91. If your compression is above 10:1 run at least 89 for a N/A car. If your car's pulling timing when you accelerate then your not getting 100% from the engine, your making less power for every ounce of gas consumed, so to get to the same place in the same ammount of time your using more throttle, and consuming more gas.
If you have the base balt, run 89. The SSs will be happier with 91 +.
09-21-2006, 09:42 AM
#44
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Logged a bunch of runs with 87 and 93.. no knock with either. You should never really feel engine knock on a newer car, if you do something is seriously wrong. Generally speaking, the only way to know if you have knock is to actually have some sort of scan tool.
09-21-2006, 12:18 PM
#46
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Originally Posted by PhantomTA
Logged a bunch of runs with 87 and 93.. no knock with either. You should never really feel engine knock on a newer car, if you do something is seriously wrong. Generally speaking, the only way to know if you have knock is to actually have some sort of scan tool.
09-21-2006, 06:18 PM
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Originally Posted by SpecialK
It wont' knock because the second it does the igntion retards the timing.
Run Premium, your car can run leaner mixtures, the fuel is less suseptible to detonation, and all thigsn previously mentioned about deposits. If you have a Forced Induction car always run at least 91. If your compression is above 10:1 run at least 89 for a N/A car. If your car's pulling timing when you accelerate then your not getting 100% from the engine, your making less power for every ounce of gas consumed, so to get to the same place in the same ammount of time your using more throttle, and consuming more gas.
If you have the base balt, run 89. The SSs will be happier with 91 +.
Run Premium, your car can run leaner mixtures, the fuel is less suseptible to detonation, and all thigsn previously mentioned about deposits. If you have a Forced Induction car always run at least 91. If your compression is above 10:1 run at least 89 for a N/A car. If your car's pulling timing when you accelerate then your not getting 100% from the engine, your making less power for every ounce of gas consumed, so to get to the same place in the same ammount of time your using more throttle, and consuming more gas.
If you have the base balt, run 89. The SSs will be happier with 91 +.
exactly and when the ecu retards the timing you lose power
which was my whole point.
09-21-2006, 06:42 PM
#48
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Originally Posted by PhantomTA
Logged a bunch of runs with 87 and 93.. no knock with either. You should never really feel engine knock on a newer car, if you do something is seriously wrong. Generally speaking, the only way to know if you have knock is to actually have some sort of scan tool.
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