87 Octane in Vette
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,674
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From: Utica NY
87 Octane in Vette
So up to this point I have never used anything less then 93 in my 2000 C5, but recently I was talking to a buddy who claims he accidently put 87 in his C5 and it ran like a bat out of hell. He called another friend and was told that if the car is tuned for lower grade fuel that it will run better. He also said that if the car starts to make a pinging noise then to move up to 91 or 93. Any truth to this ? Thanks
Thread Starter
Drifting
Joined: Apr 2007
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From: Utica NY
Race Director
Joined: Jul 2004
Posts: 16,795
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From: Lake Havasu City, AZ
I don't know how fast a bat out of hell runs....
BUT you can run the lowest level of octane that does not give knock or ping... if 87 works where ad how you drive your Vette it is fine.
Depending on your altitiude above sea level and ambient temperature that will vary.
With a Vararam, mine knocked at WOT in 1st with 94 Octane until I got a tune
BUT you can run the lowest level of octane that does not give knock or ping... if 87 works where ad how you drive your Vette it is fine.
Depending on your altitiude above sea level and ambient temperature that will vary.
With a Vararam, mine knocked at WOT in 1st with 94 Octane until I got a tune
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Pro
Joined: Oct 2007
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From: Tulsa Oklahoma
You get into a lot of trouble when you listen to your buddy's buddy. 
On a side note, there is such thing as too much octane. For a street car on pump gas though, you are not going to find that point.
On a side note, there is such thing as too much octane. For a street car on pump gas though, you are not going to find that point.
Le Mans Master
Joined: Dec 2001
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From: St. Peters MO
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With anything less than the recommended premium you WILL lose HP and your MPG WILL go down.
You can run the lower grade without major problems but it won't perform like it should.
If I wanted to use 87 octane I would have bought a car that didn't recommend premium. Saving a few bucks per tankfull seems silly in a Corvette. At least to me it does.
You can run the lower grade without major problems but it won't perform like it should.
If I wanted to use 87 octane I would have bought a car that didn't recommend premium. Saving a few bucks per tankfull seems silly in a Corvette. At least to me it does.
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,674
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From: Utica NY
With anything less than the recommended premium you WILL lose HP and your MPG WILL go down.
You can run the lower grade without major problems but it won't perform like it should.
If I wanted to use 87 octane I would have bought a car that didn't recommend premium. Saving a few bucks per tankfull seems silly in a Corvette. At least to me it does.
You can run the lower grade without major problems but it won't perform like it should.
If I wanted to use 87 octane I would have bought a car that didn't recommend premium. Saving a few bucks per tankfull seems silly in a Corvette. At least to me it does.
Thanks for the replies
Melting Slicks
Joined: Nov 2003
Posts: 2,947
Likes: 2
From: Atlanta GA
if it never had anything to do with money....nevermind, the higher octane will yeld higher compression before you start running into problems. almost common sense tells us that the higher compression you can achieve the higher the power output you will get.
...well, since fuel prices started going crazy...
Drifting
Joined: Dec 2004
Posts: 1,820
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From: San Diego
Compression ratio is a function of volume inside cylinder when piston at TDC to volume inside cylinder when its at bottom of stroke. The smaller the space at the top, the higher your compression ratio. Its a bore, stroke, volume thing. Has nothing to do with octane.
Actually, the higher the octane of fuel, the lower it's explosive power.
Corvettes have anti knock smarts built into its computer. In stock form it can adjust to octane as low as 87. Its in the owner's manual; 87 is OK but you might notice a little degradation in power.
Who said using lower octane in a corvette will net you lower gas mileage? Any concrete proof of that? If so, I'm sure is quite insignificant.
Pro
Joined: Oct 2003
Posts: 732
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From: Baxter MN
At the risk of "stealing" this thread, has anyone considered that if we were able burn straight ethanol (E100?) the octane levels would be in the 97 - 98 range. This in turn would allow compression ratios in the 11.5:1 - 12:1 range. At those levels, wouldn't we get equal or better performance, fewer emissions, and pay less money to OPEC?
Anyone with any information along these lines?
Glen
Anyone with any information along these lines?
Glen
Le Mans Master
Joined: Dec 2001
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From: St. Peters MO
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2018 C7 of Year Finalist
Huh? Higher octane equates to higher compression?
Compression ratio is a function of volume inside cylinder when piston at TDC to volume inside cylinder when its at bottom of stroke. The smaller the space at the top, the higher your compression ratio. Its a bore, stroke, volume thing. Has nothing to do with octane.
Actually, the higher the octane of fuel, the lower it's explosive power.
Corvettes have anti knock smarts built into its computer. In stock form it can adjust to octane as low as 87. Its in the owner's manual; 87 is OK but you might notice a little degradation in power.
Who said using lower octane in a corvette will net you lower gas mileage? Any concrete proof of that? If so, I'm sure is quite insignificant.
Compression ratio is a function of volume inside cylinder when piston at TDC to volume inside cylinder when its at bottom of stroke. The smaller the space at the top, the higher your compression ratio. Its a bore, stroke, volume thing. Has nothing to do with octane.
Actually, the higher the octane of fuel, the lower it's explosive power.
Corvettes have anti knock smarts built into its computer. In stock form it can adjust to octane as low as 87. Its in the owner's manual; 87 is OK but you might notice a little degradation in power.
Who said using lower octane in a corvette will net you lower gas mileage? Any concrete proof of that? If so, I'm sure is quite insignificant.
Source: http://autorepair.about.com/cs/gener...a022501a_2.htm
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