87 0ctane in a C5??
Racer
Joined: Jul 2003
Posts: 460
Likes: 0
From: N. Potomac MD
I had a C4 daily driver with 198,000 miles and all winter I used 87. In the summer it did ping and I used mid grade. In my C5 all it gets primarily is 87. What happens is that the computer goes to a different chart after it knocks a few times (no damage for a few) and then power is just reduced. Yes you can feel the difference when the computer realizes it isn't knocking and moves to another chart. Yes you feel it. However. For a daily driver and 99% of the time I am never flat out and even when I am it is never an issue. PS: MPG has nothing to do with grade of gasoline. High test and regular have the same BTU content. So when a car is doing say 65 steady state it requires about 20-25 horse power and you will see absolutely no difference between High Test and Regular. When at WOT who cares. Sooooooo I put on my special undies for the flames about to come.
Be well all.
Rich
Be well all.
Rich
Drifting
Joined: Feb 2005
Posts: 1,770
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From: in ur mirror, 'bout to pass.. CA
Octane=oxygen content. 87 octane has less oxygen molecules mixed with the refined petroleum (gas). This will produce less combustion burn, thus reducing the power output (btu's) per defined amount of gas. The result in your engine is "pre-ignition", or knock, and then when the computer senses this knock, it will retard the timing and reduce the amount of fuel being sprayed by the injectors. Over time, this behavior causes carbon buildup on your valves, pistons and spark plugs, further degrading performance. Now, why go through all that just to save some pennies? If you can't afford to fuel your vette, don't own one!
Racer
Joined: Jul 2003
Posts: 460
Likes: 0
From: N. Potomac MD
Oh so judgemental. Live and let live. BTW: oc·tane (¼k“t³n”) n. 1. Any of various isomeric paraffin hydrocarbons with the formula C8H18, found in petroleum and used as a fuel and solvent. 2. An octane number. No oxygen there.
Safety Car
Joined: Nov 2004
Posts: 4,514
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From: Si Vis Pacem Habeatis Filios Vestros, Ad Bellum Parare Modo
Originally Posted by CorvetteNoobie
The first car I ever had was my grandma's 1964 thunderbird in 1989 (22,000 original miles at that time) with the 429 V8 option, now that car required 93 octane for sure, it almost vommited with anything else.
Instructor
Joined: Mar 2005
Posts: 200
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Seriously bubble? This confuses me, I am not a Thunderbird nut, but my Grandma's car looked like the Thelma/Louis style and I was sure those ran only until 1966, yet hers/mine had a 429 v8 sticker on the air filter flying saucer thing. I thought the 1968 was when they got ugly in my opinion, are you sure the 429 was in the Thelma style Birds? My car had the sequential tail lights, if that helps. We must solve this mystery!
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I agree that it can be used and will not harm the car. At least around here, some gas stations sell 89 octane for the same as 87 octane, so I have used the 89 - did not really notice a loss of performance.
Team Owner
Joined: Sep 2002
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From: Bonita Springs, Florida
Lets say there is a 25 cent per gallon difference in the price per a gallon between 87 and 92-93 octane fuel. Lets say the average driver put 12,000 miles per year on their Vette (most put less than half of that many miles on their Vettes since they are primarily pleasure vehicles). For arguments sake lets be conservative and estimate the average combined MPG at 18.
You will save $13.89 per month or $166.67 per year and chance damaging your engine by using low octane fuel in your Corvette. The price of a set of fancy floor mats. Bring lunch once a month and save the $14. Probably half that much or less for most people who use their cars on nice days only.
my 2 cents.
You will save $13.89 per month or $166.67 per year and chance damaging your engine by using low octane fuel in your Corvette. The price of a set of fancy floor mats. Bring lunch once a month and save the $14. Probably half that much or less for most people who use their cars on nice days only.
my 2 cents.
7th Gear
Joined: Apr 2004
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From: Asheboro NC
Originally Posted by CorvetteNoobie
In college one of my business professors (in Texas) explained to us some of the hoodwinking in the gas industry. First off, the same tankers go around to the same gas stations, i.e. screw us if we think Chevron with Techron is really any different than Exxon or whatever.
The Exxon station my grandfather owns has 2 inground tanks. A tank of 87 octane and a tank of 93 octane. Mid grade is made by the mixing of the 2 grades of gas by a mixer located inside the gas pump.
Different name brands of gas also have different kinds of additives in the gas.
Originally Posted by CorvetteNoobie
I wonder if most gas stations just have one giant tank sending the same gas to all three pumps, or who knows if a gas station actually puts the right gasoline in the right tank. I assume we don't waste tax money paying some guy to spot test gasoline.
Team Owner
Joined: Aug 2004
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From: The Beautiful Pacific Northwest
St. Jude Donor '05-'06-'07-'08-'09, '14-'15-'16-'17-'18
To answer your original question...It won't hurt to put in a couple of gallons to last you until you can find the higher grade fuel.
But...
My Red Racer gets the best... Chevron Supreme. Anything less is like feeding a world class athlete a steady diet of hamburgers and fries. It'll fill you up, but your performance will suffer...
But...
My Red Racer gets the best... Chevron Supreme. Anything less is like feeding a world class athlete a steady diet of hamburgers and fries. It'll fill you up, but your performance will suffer...
Melting Slicks
Joined: Mar 2004
Posts: 3,002
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From: Surrey BC
i know it makes a couple of dollar difference at the pump....thats why i started using 87 when i got her too...it started making some weird noises...so i switched back to 94....the sound disappeared...id say fill it with the best stuff out there!!! well worth the extra couple of dollars to keep her running good! 
Burning Brakes
Joined: Jun 2004
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From: Nesconset NY
St. Jude Donor '04 & '05
Originally Posted by v.vet's C5
The Corvette manual says it's okay....the computer recognizes the lower octane fuel but performance is diminished. However, since it not recommended and just my 2 cents, I didn't spend good money for diminished results. That's just not right. 
in a pinch. Chevron and V-Power seems to be the best I've found. 
