I know that the SC engine likes the higher octane fuel. My question to the people who own them is this;
What kind of performance loss do you notice if you use lower octane fuel?
<img src="http://www.j-body.org/registry/kermit/personal_pic.jpg">
Perhaps you would have a better chance of this getting answer on a Colbalt forum? Or even the Other Cars forum?
-Chris
yea i would say posting this on cobaltss.net....
but ughh when i test drove one the guy said you can use whatever you want, its just the motor will adjust and therefore not put out as much power on the lower octane
its probably not much of a difference....but i duno
I do not own one, but just the fact that there supercharged leads me to believe mid-grade would produce the best power outputs.
Correct me if I'm wrong.
Always high octance with a forced inducted motor.
03ecols 5 spd wrote:Always high octance with a forced inducted motor.
agreed.
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CobaltSS.net - Chevy Cobalt Enthusiasts
not to be an ass, but if you spent the money for a cobalt SS, why dont u just spend the extra 20 cents on the fuel??
My owners manual says 93 octane, but i only fill up with sunoco's 94 octane.
-Adam
John H wrote:not to be an ass, but if you spent the money for a cobalt SS, why dont u just spend the extra 20 cents on the fuel??
ding ding ding! seriously....20 cents extra on a gallon of gas, times maybe 11 gallons of gas, is just over 2 bucks...is 2 dollars really worth losing the performance?
Forced induction really needs premium.
You CAN run on other grades and most cars' ECU is smart enough to sense that and adjust the timing and other factors, however its not a good idea. You will DEFINETLY experience a performance drop.
It might not be that much, but you will see it. I can notice the difference between 91 and 93 in my car.
Again, its not that much difference in cost. If you don't want to buy premium, why buy a car which calls for it....go buy a Prius.
Does the owners manual of the cobalt really say to use 93 octane? Wow.. that'd be tricky as most gas stations around here don't have anything higher than 91/92 you can get 94 at sunoco but they aren't exactly the most common gas stations around here.
I think if you decide to buy a cobalt SS you should be aware that the car needs premium and accept the fact that you're gonna have to pay that much more at the pump. It's a price you pay for that added performance.
I think sales guys are just saying that it's OK so they don't lose the sale due to people being afraid of the cost of having to fill with premium.
My RSX-S needs premium and supposedly the ECU will retard the timing enough that I could run regular but there's no way in hell a drop of regular is gonna see the inside of my gas tank unless I had absolutely no choice.
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Why do people get stuck on this? Seriously, if that is what is keeping a person from buying a certain car, then you really should be looking at a Toyota Prius.
Now to answer your question, I don't have a boosted car, but on my GTO, right inside the fuel door, there is a big sticker that says "Premium Fuel Recommended." Now I have gone both routes, (meaning using 87 octane vs. 93 octane, both from Mobil), and while I don't have any noticeable difference in power, the car does tend to drink 87 like its water.
But I do agree with the guys above about forced induction = higher octane gas.
Owning a high-performance car, whether it is boosted or not, is going to cost more money. Either accept it, or look into getting the car I mentioned above.
Rob
Sold 2/2/05
Recommended? My fuel door says "PREMIUM FUEL ONLY".
I use premium even if I don't have too. Even if there isn't a performance gain. If only for the silly idea or peace of mind that my new car is going to run better and longer if i spend an extra buck at the station.
Emor8t (IDI....) wrote:I use premium even if I don't have too. Even if there isn't a performance gain. If only for the silly idea or peace of mind that my new car is going to run better and longer if i spend an extra buck at the station.
The only benefit you are getting out of this might be cleaner gas.
If your ECU is not set up to benefit from higher octane gas, there is no benfit to this at all and you are essentially wasting money.
All turbo and supercharged cars are going to recomend a min of 91. Can't do 93 since a lot of places don't even carry 93. More so on the west coast. Either way, you are foolish if you are running low octane for extended periods of time.
Waste of money. The idea that the gas is cleaner is just perpetuated by the gas companies to get you to spend extra on the more profitable higher octane.
There's a huge long thread about this somewhere around here. Either in Maintenance or Performance. The fact is, there is no benefit to running higher octane gas than your car is made for. There are very specific reasons for running higher octane and none of them have anything to do with it being somehow "better" gas.
My manual for my red line says 91 octane minimum, 93 and 87 and 89 is whats available here so i use 93.
To be honest...Before i ordered my SS I was just running through all the costs associated with the car, and when i heard about the 91 octane minimum i was crushed.
I was so pissed that i had to get the high test stuff i wasn't going to get the car.
THEN....Common sense kicked in and i realized that the average difference in 87-91 octane was $0.10 do the math and it's no more than $5-10 more a tank...If you can afford the SS you can afford to bag a lunch once a week to make up the difference. !
Wow. Not being on here as much as used to be, I forgot how much a guy can get flamed for asking a question.
What I was going after with the question is exactly what was stated: What kind of performance drop do you notice? It's not a matter of .05/L means I won't buy the car. The tank is 51.1L. At $.10/L for higher octance, if an extra $5.11, (regardless of the base price for high octane) per tank means that I don't buy the car, then I shouldn't be buying any car in the first place, Prius included.
What I was getting at is this; is the high octance gas
necessary. Last time I checked, nobody on this board trusted everything GM has said 100% for their entire life. I was looking for what people have experienced with the vehicle in real world conditions.
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It's not really a performance issue, but more of a safeguard for performance.
With forced induction, spray, or high compression, you need high octance to prevent pre-ignition, or "knock", or "detonation", all mean the same, and can potenetially grenade a motor.
I know the cost of gas sucks, and premium makes it worse, but you buy a performance motor, you have to factor the extra cost into the equation of ownership.
Plus, they usually require more TLC, than their normal cousins.
Its not just a GM thing. Any car which runs any sort of FI will certainly call for premium. Even certain cars which just run a very high compresion will call for premium.
Its hard to put a certain rating on the performance loss you will experience. Maybe a few tenths of a second. It will be more noticable in a butt dyno sense with throttle response.
03ecols 5 spd wrote:It's not really a performance issue, but more of a safeguard for performance.
With forced induction, spray, or high compression, you need high octance to prevent pre-ignition, or "knock", or "detonation", all mean the same, and can potenetially grenade a motor.
I know the cost of gas sucks, and premium makes it worse, but you buy a performance motor, you have to factor the extra cost into the equation of ownership.
Plus, they usually require more TLC, than their normal cousins.
yep, he's got it right. you will notice a performance drop in the lower octane, but that drop is also telling you that the engine is about this close >[ ]< to kicking itself apart. it's all a matter of temperature vs. octane. forced induction creates about twice the temperature in the combustion chamber before combustion as NA engines. so you need that higher octane fuel to keep from preignition. yes, you
can use a lower octane than 91, but the risk to your engine is not worth the $5 you're saving. I own a Grand Prix GTP supercharged, and i put the good stuff in every time (i live in indiana, so we get the good 93 octane stuff). every once in a while i'll even put an octane boost in to rais the level. Im not rich, no where near, but i dont miss that extra $5, especially when i think about how it's makin my car last longer... and that i can beat the crap out of a modded mustang gt in my groccery getter.
Andy
it's not how fast you go, it's how you get there that counts.
ZZP XP cam, 1.6 rockers, 105# springs, speedbuilt FWI, 3.3" modular pulley, TOG headers,
3" exhaust, flomatched injectors
'97 GTP 14.06@100.6mph pre cam w/ 3.5" pulley, I/E
Im always going to run 91 in my SS.
Yeah, do it.
It sucks for the wallet initially at the pump, but you got the SS for a reason.
It's not worth it to put regular in a car that REQUIRES high-test.
For all you new car owners, break the motor in right, don't jump on it until after 1K.
The reward will come at around 35k.
(change the oil at the 1k mark, and again at 3500, and so on and so forth)
The first thousand is more crucial than most realize as far as how the life of the motor will be, and how much it will put down afterwards.
