Wrong octane
Thread Starter
Burning Brakes
Joined: Aug 2008
Posts: 1,008
Likes: 82
Wrong octane
Hey guys did a search but couldn't come up with anything that answered my question.
Today I went to fill her up and I accidentally had a brainfart and filled her with **** (87) octane by accident. The car still had 8 gallons of 91 octane from the last fill up. Do I need to take a road trip to burn off this tank or will I be fine as long as I don't go out drag racing. I know my c6 I used 87 all the time with no apparent issues, but with the stingray being required 91 im worried. I called the dealership and they said to go to autozone and buy octane booster which I did but at 10 a pop I only got 1 bottle. Guess I will baby it for 300 miles or so
The bright side was the fill up only cost 40.00
Today I went to fill her up and I accidentally had a brainfart and filled her with **** (87) octane by accident. The car still had 8 gallons of 91 octane from the last fill up. Do I need to take a road trip to burn off this tank or will I be fine as long as I don't go out drag racing. I know my c6 I used 87 all the time with no apparent issues, but with the stingray being required 91 im worried. I called the dealership and they said to go to autozone and buy octane booster which I did but at 10 a pop I only got 1 bottle. Guess I will baby it for 300 miles or so
The bright side was the fill up only cost 40.00
Pro
Joined: Jul 2014
Posts: 602
Likes: 119
From: Southern Ontario
Hey guys did a search but couldn't come up with anything that answered my question.
Today I went to fill her up and I accidentally had a brainfart and filled her with **** (87) octane by accident. The car still had 8 gallons of 91 octane from the last fill up. Do I need to take a road trip to burn off this tank or will I be fine as long as I don't go out drag racing. I know my c6 I used 87 all the time with no apparent issues, but with the stingray being required 91 im worried. I called the dealership and they said to go to autozone and buy octane booster which I did but at 10 a pop I only got 1 bottle. Guess I will baby it for 300 miles or so
The bright side was the fill up only cost 40.00
Today I went to fill her up and I accidentally had a brainfart and filled her with **** (87) octane by accident. The car still had 8 gallons of 91 octane from the last fill up. Do I need to take a road trip to burn off this tank or will I be fine as long as I don't go out drag racing. I know my c6 I used 87 all the time with no apparent issues, but with the stingray being required 91 im worried. I called the dealership and they said to go to autozone and buy octane booster which I did but at 10 a pop I only got 1 bottle. Guess I will baby it for 300 miles or so
The bright side was the fill up only cost 40.00
Race Director
Joined: May 2001
Posts: 15,323
Likes: 2,077
From: Guelph, Ontario
Don't bother with the octane boost, things will be fine without it (I'd be more worried about what effect the chemicals in the octane boost might have on the fuel system to be honest). The computer will back off a little bit of the timing at full throttle in the higher gears, but probably won't take out much if any timing at all in first or second gear. I'd suggest taking it on a bit of a highway drive to burn off some fuel quickly, and then top it off with premium once you've burned off a 1/2 tank or so.
Your profile doesn't say where you live, is it a particularily hot area? The computer will back off a lot more timing if it's 100 degrees outside compared to 75 or 80 for example. Even with 100% 91 octane it would probably pull out a few degrees of timing in 4th-7th gear if it's 100 degrees outside.
Your profile doesn't say where you live, is it a particularily hot area? The computer will back off a lot more timing if it's 100 degrees outside compared to 75 or 80 for example. Even with 100% 91 octane it would probably pull out a few degrees of timing in 4th-7th gear if it's 100 degrees outside.
Race Director
Joined: Jun 2000
Posts: 13,733
Likes: 66
From: Hurst, TX USA
The computer will adjust the timing if it feels any knocking. I would take it easy for a couple tanks, no WOT for a while. I ran 86 in my C6 for a while as a test and all that happened was about a 2 mpg worse fuel consumption.
Advanced
Joined: May 2014
Posts: 81
Likes: 1
From the manual (9-51):
Use premium unleaded gasoline with a posted octane rating of 91 or
higher. If the octane is less than 91, you could damage the engine and
may void your vehicle warranty. If heavy knocking is heard when
using gasoline rated at 91 octane or higher, the engine needs service.
Just FYI.
Use premium unleaded gasoline with a posted octane rating of 91 or
higher. If the octane is less than 91, you could damage the engine and
may void your vehicle warranty. If heavy knocking is heard when
using gasoline rated at 91 octane or higher, the engine needs service.
Just FYI.
Safety Car
Joined: Feb 2007
Posts: 4,939
Likes: 448
From: CHOCOWINITY NC
Despite those warnings I wouldn't worry... The ECU has 2 timing maps, high and low. It will shift to the low timing map when Detonation is discovered. Just drive it easy for half a tank and re-fill with 93. If you're a worry wart, put some octane booster in.....I bet the dealers put 87 in a lot of times for the original delivery fill...
Melting Slicks<br><img src="/forums/images/ranks/3k-4k.gif" border="0">
Joined: Jul 2002
Posts: 3,055
Likes: 276
From: Enterprise AL
I'd recommend adding a bottle of good octane booster. Some will add a full three points for 20 gals (87 to 90) so you'd be a lot safer (and more piece of mind).
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Team Owner
Joined: Mar 2012
Posts: 49,212
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From: Best Island in the U.S.
St. Jude Donor '12 thru '17
Many owners forget that their C7 is a Chevrolet. It's a car. One tank of 87 octane gas won't hurt anything, yet many would buy octane boost, drive it like an old lady and keep topping off with 93 octane, etc, etc, etc.
Le Mans Master
Joined: Apr 2012
Posts: 6,956
Likes: 4,811
From: Camden SC
The premium around here is 93 octane. About every 4th or 5th tank, I will put in 1/2 tank of midgrade (89 octane). I figure it averages out to 91. Don't know exactly why I do it, maybe just keeping a dollar or two of my money from going to the oil companies...
Advanced
Joined: May 2014
Posts: 81
Likes: 1
Even though the manual preaches doom and gloom about nothing less than 91 Octane I am sure you are fine. It's not like you put diesel in the car! Just cruising you will be fine, it probably would be more of an issue at the track.
We should be more worried about properly cleaning our windshields!
Racer
Joined: Sep 2012
Posts: 342
Likes: 52
With your original 8 gallons of premium, you now are running essentially mid grade gas (more or less half reg., half high test). That is in fact what mind grade at the pump is, a mix of reg. and premium (they don't have 3 tanks in the ground).
Quote: (From 'there's an app for this');
<It’s perfectly fine to combine different octane levels of gas, as long as they’re both unleaded. The only difference between the two blends is their octane content. It’s like if you had really sweet iced coffee and an only slightly sweetened batch of ice coffee and you wanted just a middle level of sweetness coffee and did it by making a blend of the two. It’s all the same coffee, only the sugar levels are different.>
As long as you're not flooring it or lugging it (where detonation may be a factor), it makes absolutely no difference to the engine. On long trips with highway cruising only (no racing), you can run regular for all the engine cares...what does it take at 75 mph, 15 horse power?
No, I'm not recommending anyone run cheap gas. Just making the point that it is not the end of the world. As long as you're not pushing detonation, the engine doesn't know or care what grade fuel you use.
Quote: (From 'there's an app for this');
<It’s perfectly fine to combine different octane levels of gas, as long as they’re both unleaded. The only difference between the two blends is their octane content. It’s like if you had really sweet iced coffee and an only slightly sweetened batch of ice coffee and you wanted just a middle level of sweetness coffee and did it by making a blend of the two. It’s all the same coffee, only the sugar levels are different.>
As long as you're not flooring it or lugging it (where detonation may be a factor), it makes absolutely no difference to the engine. On long trips with highway cruising only (no racing), you can run regular for all the engine cares...what does it take at 75 mph, 15 horse power?
No, I'm not recommending anyone run cheap gas. Just making the point that it is not the end of the world. As long as you're not pushing detonation, the engine doesn't know or care what grade fuel you use.
Hey guys did a search but couldn't come up with anything that answered my question.
Today I went to fill her up and I accidentally had a brainfart and filled her with **** (87) octane by accident. The car still had 8 gallons of 91 octane from the last fill up. Do I need to take a road trip to burn off this tank or will I be fine as long as I don't go out drag racing. I know my c6 I used 87 all the time with no apparent issues, but with the stingray being required 91 im worried. I called the dealership and they said to go to autozone and buy octane booster which I did but at 10 a pop I only got 1 bottle. Guess I will baby it for 300 miles or so
The bright side was the fill up only cost 40.00
Today I went to fill her up and I accidentally had a brainfart and filled her with **** (87) octane by accident. The car still had 8 gallons of 91 octane from the last fill up. Do I need to take a road trip to burn off this tank or will I be fine as long as I don't go out drag racing. I know my c6 I used 87 all the time with no apparent issues, but with the stingray being required 91 im worried. I called the dealership and they said to go to autozone and buy octane booster which I did but at 10 a pop I only got 1 bottle. Guess I will baby it for 300 miles or so
The bright side was the fill up only cost 40.00
Instructor
Joined: Aug 2014
Posts: 186
Likes: 60
From: Carmichael Ca
Wrong octane response
Hey guys did a search but couldn't come up with anything that answered my question.
Today I went to fill her up and I accidentally had a brainfart and filled her with **** (87) octane by accident. The car still had 8 gallons of 91 octane from the last fill up. Do I need to take a road trip to burn off this tank or will I be fine as long as I don't go out drag racing. I know my c6 I used 87 all the time with no apparent issues, but with the stingray being required 91 im worried. I called the dealership and they said to go to autozone and buy octane booster which I did but at 10 a pop I only got 1 bottle. Guess I will baby it for 300 miles or so
The bright side was the fill up only cost 40.00
Today I went to fill her up and I accidentally had a brainfart and filled her with **** (87) octane by accident. The car still had 8 gallons of 91 octane from the last fill up. Do I need to take a road trip to burn off this tank or will I be fine as long as I don't go out drag racing. I know my c6 I used 87 all the time with no apparent issues, but with the stingray being required 91 im worried. I called the dealership and they said to go to autozone and buy octane booster which I did but at 10 a pop I only got 1 bottle. Guess I will baby it for 300 miles or so
The bright side was the fill up only cost 40.00
Instructor
Joined: Aug 2014
Posts: 186
Likes: 60
From: Carmichael Ca
As per previous posts there should be no problem; however, if you are still concerned and for future reference just go to the nearest local airport and put in some aviation gas. At 105 octane your corvette will love it!
Melting Slicks
Joined: Nov 2013
Posts: 2,016
Likes: 73
From: Texas
I believe avgas is leaded. If that’s the case, death to the catalytic converter and warranty won’t cover it. Don
Race Director
Joined: May 2008
Posts: 10,742
Likes: 629
From: Manheim Pennsylvania
NO!!! Absolutely do not do that, 100LL is highly leaded and will ruin emission components with as little as a few gallons. I sell the stuff (Reading Jet Center, Reading PA) so know first hand. There never was a 105 octane Avfuel. Yesteryear we had 80/87 red, 91/96 blue, 100/130 green, 115/145 purple. All these have been replaced and now, 100LL (blue) is the only grade sold in this country.
Last edited by Larry/car; Aug 13, 2014 at 09:44 PM.