What Octane is safe in a C5?
Thread Starter
Drifting
Joined: Jan 2005
Posts: 1,342
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From: Arlington TX
What Octane is safe in a C5?
I'm just curious, I've been using premium, but 32 dollar tank fills are kicking my ***, Anyone have any experience, the vette has a knock sensor, so at worse you would loose power, however, what octans have you experimented with? 87-89-91-93 ? I've been using 93.
Team Owner
Joined: Jun 2004
Posts: 96,209
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From: Houston Texas
St. Jude Donor '09
Originally Posted by RandW
I use premium only, what are you really saving? At $.10 a gal and 20 gal. it's only $2
Drifting
Joined: Jan 2005
Posts: 1,419
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From: Oceanside, CA
Pop open your gas door and look at the bottom of the door. It says, "Premium Recommended." Owners manual also says Premium.
For what it's worth, the gas in Arizona where I live really blows and like California it only goes up to 91 octane. I filled up and put a bottle of octane boost in and my average fuel economy went up .5 within 40 miles today. Keep in mind that this even occured with me stopping and easing out of first then power shifting through fourth at my shift light, 5 different times during that 40 miles.....
My car just seems to run better and get better gas mileage the higher octane I run.
Doesn't make sense to me to own a Corvette and cripple it by running low grade fuel.
For what it's worth, the gas in Arizona where I live really blows and like California it only goes up to 91 octane. I filled up and put a bottle of octane boost in and my average fuel economy went up .5 within 40 miles today. Keep in mind that this even occured with me stopping and easing out of first then power shifting through fourth at my shift light, 5 different times during that 40 miles.....
My car just seems to run better and get better gas mileage the higher octane I run.
Doesn't make sense to me to own a Corvette and cripple it by running low grade fuel.
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Le Mans Master
Joined: Nov 2001
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From: Toronto
Originally Posted by 5.0_CJ
I'm just curious, I've been using premium, but 32 dollar tank fills are kicking my ***, Anyone have any experience, the vette has a knock sensor, so at worse you would loose power, however, what octans have you experimented with? 87-89-91-93 ? I've been using 93.
Well, get a Honda. 
Race Director
Joined: Nov 2003
Posts: 12,346
Likes: 5
From: Mustang OK
I use 91 octane or sometimes higher.
From the 2003 Owner's manual:
Gasoline Octane
Use premium unleaded gasoline with a posted octane of 91 or higher for best performance. You may also use middle grade or regular unleaded gasoline rated at 87 octane or higher, but your vehicle’s acceleration may be slightly reduced. If the engine octane is less than 87, you may get a heavy knocking noise when you drive. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, you might damage your engine.
From the 2003 Owner's manual:
Gasoline Octane
Use premium unleaded gasoline with a posted octane of 91 or higher for best performance. You may also use middle grade or regular unleaded gasoline rated at 87 octane or higher, but your vehicle’s acceleration may be slightly reduced. If the engine octane is less than 87, you may get a heavy knocking noise when you drive. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, you might damage your engine.
Race Director
Joined: Aug 2000
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Originally Posted by ROJ#79
89 octane works fine for normal driving! 
correct me if i'm wrong, but i think there's a federal law or something, that says the manufacturer cannot sell a car that won't run on 87 octane. it may not run at peak performance, but at normal operating conditions, it will run "OK" . a friend of my accidentally filled up her '97 with regular. we were coming back from carlisle, and the car seem to run just fine at normal driving conditions. i typically use 89 octane for my '85 driver, and when i had my y2k coupe i usually ran 89. as for my z06, haven't ran anything but 92-93 octane (yet). there are a lot of people that relate octane to gas quality - they will drive out of their way for 93-94 octane thinking it's a better gas. lets face it, unless you are racing and need that extra edge, 89 is just fine for normal driving in a computer controlled corvette.
Advanced
Joined: Nov 2004
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I thought the higher octan or better fuels also clean injectors better i have always used amaco gold which has been bought by bp i talk to a fuel delivary guy and was told most all fuels come from the same place and it was the additives that was diff, but he tols gold was shipped on separate container and was a better fuel i use it in all my cars that require preium fuels and have never had injector problems my 2cents
Racer
Joined: Oct 2003
Posts: 389
Likes: 1
From: Denver co
The LS1 or LS6 do not have a very high compression ratio like some european cars.
Plus the car has a knocking detection.
Any gas normally work fine.
If you want the maximum performance the 91 is the one.
Going higher is wast of money unless you modified your car and increase the compression ratio.
Plus the car has a knocking detection.
Any gas normally work fine.
If you want the maximum performance the 91 is the one.
Going higher is wast of money unless you modified your car and increase the compression ratio.
Racer
Joined: Jan 2005
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From: Summit Station Ohio
St. Jude Donor '05-'06-'07-'08-'09-10-'11-'12-'13-'14-'15-‘16-‘17
Originally Posted by 5.0_CJ
I'm just curious, I've been using premium, but 32 dollar tank fills are kicking my ***, Anyone have any experience, the vette has a knock sensor, so at worse you would loose power, however, what octans have you experimented with? 87-89-91-93 ? I've been using 93.
Don't feel too bad, our tank fills are closer to $45.
Melting Slicks
Joined: Mar 2003
Posts: 2,744
Likes: 9
From: FL
Cruise-In VI Veteran
It will run just fine on 87 and is perfectly safe to use... It will NOT harm your car/motor. This has been discussed here on the board before.
BUT, you will most likely get a lil' more power with a higher octane fuel due to the computer running more timing. The computer will pull out timing if it detects pinging/detonation. You have less of a chance of ping on higher octane fuel.
Octane slows the burn of fuel and makes it less volatile. Technically speaking (with combustion engines, for max perf), you want to run the lowest octane possible without "any" detonation (inaudible or audible).
BUT, you will most likely get a lil' more power with a higher octane fuel due to the computer running more timing. The computer will pull out timing if it detects pinging/detonation. You have less of a chance of ping on higher octane fuel.
Octane slows the burn of fuel and makes it less volatile. Technically speaking (with combustion engines, for max perf), you want to run the lowest octane possible without "any" detonation (inaudible or audible).
Thread Starter
Drifting
Joined: Jan 2005
Posts: 1,342
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From: Arlington TX
Good arguments in here, what happened seems to be the general idea I had. Seems like 87 will do just fine for normal driving to and from work. I understand the whole "wtf, a vette and your bitching about gas prices" Well, if I can some some money going to and from work, I'll do it... I Drive about 35 miles a day to and from work, its a pretty uneventful travel. And yes the DOT does regulate all vehicles to operate at 87 octane, even the enzo does this, not optimal, but acceptable. If I plan on pounding on it, I'll run high octane, but for to and from work 87 should be fine, even if I get some crap gas the knock sensor will help me, and I've got a very keen ear to detonation if worse be. Good discussing, I appreciate the replies.
