Which octane do you use?
Thread Starter
Instructor
Joined: Oct 2009
Posts: 116
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From: pinehurst nc
Which octane do you use?
I've had several C6 Corvettes and have used premium fuel in all of them. Today a dealer told me that I should be using regular fuel, and will not notice any difference in performance. What do you think?
Intermediate
Joined: Jun 2011
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Base C6 was tuned to run 91. You can run 87 without problems, but you may notice a small performace decrease (Due to timing changes to prevent knock). Running anything higher is a waste of money unless you have power adders or are going to tune it.
Pro
Joined: Jul 2011
Posts: 604
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From: Boynton Beach, Plano FL, TX
Here we go......
By the way I'm an ex dealer and run regular...have for years... No issues...i know im in the minority on this one, but over the years i have been told by several factory engineers its basically a non issue for the car... And of course 98% of my driving nowadays is cruising. If I expect I will be pushing the car I'll top off with Premium.... I'm talking LS2 and 3... on LS7 premium is needed....
By the way I'm an ex dealer and run regular...have for years... No issues...i know im in the minority on this one, but over the years i have been told by several factory engineers its basically a non issue for the car... And of course 98% of my driving nowadays is cruising. If I expect I will be pushing the car I'll top off with Premium.... I'm talking LS2 and 3... on LS7 premium is needed....
Race Director
Joined: Jul 2010
Posts: 10,548
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From: Upstate NY
I use 93 because it happens to be the premium grade where I usually gas up. I would be comfortable using 91 or whatever the manual specifies. Why do any less for a $50,000+ car?
Last edited by C7Joy; Aug 12, 2011 at 12:34 PM.
Race Director
Joined: Mar 2011
Posts: 13,262
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From: SW Florida
2021 C6 of the Year Finalist - Modified
Sure you can use regular gas, but when the engine knock sensors sense even the slightest amount of detonation (from the low octane gas), the PCM will pull timing out of it and you will lose HP.
The problem will worsen in the hot sumertime when engine cylinder head temps go way up.
Not a great idea ... stick to what the owner's manual tells you. GM knows a little more about these engines than some guy at a Chevy dealership.
The problem will worsen in the hot sumertime when engine cylinder head temps go way up.
Not a great idea ... stick to what the owner's manual tells you. GM knows a little more about these engines than some guy at a Chevy dealership.
Team Owner
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From: I live my life by 2 rules. 1) Never share everything you know. 2)
St. Jude Donor '11-'12-'13, '16-'17-'18
Stupid reason to use regular....
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From: Rochester, NY
Melting Slicks
Joined: Mar 2007
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From: Summerton SC
Tech Contributor
I use 93, but one time I filled with 87, to see ... and I saw 
A serious difference in power and response. Sure it ran okay, but I couldn't wait to empty the tank.
I hope one day to use propane or natural gas!
A serious difference in power and response. Sure it ran okay, but I couldn't wait to empty the tank.
I hope one day to use propane or natural gas!
Team Owner
Joined: Aug 2007
Posts: 136,140
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From: I live my life by 2 rules. 1) Never share everything you know. 2)
St. Jude Donor '11-'12-'13, '16-'17-'18
Team Owner
Joined: Sep 1999
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From: Springfield MO
My Z06 REQUIRES a minimum of 91 octane but GM engineers recommend that I use 93. I only run 94 octane without any ethanol crap added. All 87 and 89 octane around here is E10 and I won't put it in my car.
Even if I could run 87 octane, the $150-$200 a year savings isn't worth it. I purchased a $80,015 high performance car and trying to save $150/$200 a year on gas is stupid.
Even if I could run 87 octane, the $150-$200 a year savings isn't worth it. I purchased a $80,015 high performance car and trying to save $150/$200 a year on gas is stupid.
Pro
Joined: Aug 2009
Posts: 586
Likes: 131
From: Carlisle PA
I have a 2010 Grand sport now and had a 05 and have always used medium grade (89 octane). Never an ounce of knocking. I tried 93 octane and did not notice any performance or gas mileage improvement. I will continue to use 89 octane from here on out.
Instructor
Joined: Jun 2011
Posts: 238
Likes: 1
From: Clayton North Carolina
Stations where I live offers 87, 89, and 93 octane. I use the 93 because the manual recommend 91 octane. For no more than it cost I figure a $50k plus vehicle is worth it. It is kind of like changing the oil, go through a quick change location and let them put cheap oil and filter or follow the manual and spend a few bucks. Our cars only deserve only the best!!
Le Mans Master
Joined: Dec 2007
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From: Milford NH
Le Mans Master
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From: "Nowhere Man"
St. Jude Donor '13-'14-'15-'16-'17-'18-'19-'20-'21-'22
93 only. Mobil, Sunoco, Shell etc. Top tier Just like the manual states. I did have a station accidently put regular(I guess force of habit). Car still ran fine. When I got to a half a tank I refilled with premium. No harm done.
I just wanted to add I got a 2011 Ford Taurus SHO. That manual reads just like the vette. Will run on regular, recommend premium. That car gets the plus, 89-91 depending on which station. That car also runs just fine.
I just wanted to add I got a 2011 Ford Taurus SHO. That manual reads just like the vette. Will run on regular, recommend premium. That car gets the plus, 89-91 depending on which station. That car also runs just fine.
Last edited by LUVMINE; Aug 12, 2011 at 02:06 PM. Reason: Addition