Octane test report
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Drifting
Joined: Jul 2011
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From: Bay Point California
Octane test report
Just got back from filling up the Vette on Chevron "mid grade". Second tank actually. No problems what's so ever. No pinging during hard acceleration, nothing. Car runs great! Next tank will be regular.
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I have, on occasion, run mid-grade in mine and did not notice any pinging or reduced performance. I do run premium though when available.
Melting Slicks
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From: Russell Ontario
St. Jude Donor '09
I run regular in my 04 all the time , in fact I drove it back from California and never had any issues , it will ping if I'm real hard on it , but regular driving 's no problems at all . Ron
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Drifting
Joined: Jul 2011
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From: Bay Point California
Thread Starter
Drifting
Joined: Jul 2011
Posts: 1,509
Likes: 10
From: Bay Point California
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From: Palm Harbor Fl
Really? Have you been scanning your knock counts? What were they before and after the switch? How much timing is the pcm pulling because of detonation? Just because you can't feel or hear the pinging it doesn't mean it's not happening.
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Premium or regular ?
So that's pretty clear, the engineers at GM power trains division really think using at least 91 octane fuel will give your car the necessary additive to ensure you and your engine will have a long life. And they hope you'll do that and you and you car will both run better and last longer. I personally seek out a ("Top Tier") - You can look it up on the web, gasoline whenever I drive and I refuse to put any regular low grade Gasoline in my Corvette. I did the math the other day, If I filled up the 17 gallon tank with regular vs, Premium it comes out to be $1.54 cents difference. Now I ask you, If you want to fuel your Corvette like a Cobalt, then why didn't you buy the Cavalier or Cobalt or whatever runs swell on cheap gas. I mean does $2.00 difference really mean that much to you ?. . . I paid $49K for my 2003 50th anniversary coupe when I bought it. It gets everything the GM maintenance schedule dictates.
If your interested "Road & Track magazine this month has a great article about what is in your gasoline and whats not and why it's in there, some science and some political, but it a good read anyway. But I hear this discussion on the forum often about using cheap or Ethanol laden fuels. And I don't mean any disrespect, but why did you buy a Corvette ? Why not buy a sporty Ford Focus or a really nice Toyota or Honda, Look Honda's are a great little car and you can do all kinds of things to a Honda that same as a Corvette and you can run on the cheapest gasoline you can fine. But I can assure you if and when I have the Vette up around the century mark, i sure am glad I've got a fuel the will get me there and bring me home and idle as smooth as silk in the driveway. but People are people, Good luck with the cheap fuel, in a year or two and you go out on a cool day and you go to start your Corvette and it is so sick the thing won't even catch. But you can always sign up with AAA !
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Drifting
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From: Bay Point California
Come on. The car is fine. I am not going to go out and wreck my Vette. It's a f'n science deal. It has performed perfectly so far. As soon as it tell's me other wise we will be fine. If it pings I think I might hear it. So far we have had no knock counts. This car hauls ***.
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From: Horncastle Lincolnshire, England
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The knock sensor is retarding the ignition to compensate for the lower octane. That means you're getting less performance and worse gas mileage.
At least you're bucking the trend. Most guys around here are loking for mods to increase performance.
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From: Palm Harbor Fl
Come on. The car is fine. I am not going to go out and wreck my Vette. It's a f'n science deal. It has performed perfectly so far. As soon as it tell's me other wise we will be fine. If it pings I think I might hear it. So far we have had no knock counts. This car hauls ***.
Melting Slicks
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From: Russell Ontario
St. Jude Donor '09
Of course it has nothing to do with the engineers being in bed with the gas companys.Same scam has GM DEXOS oil only in 2011 or newer cars . I called Texas where the lab ENGINEER laughed and said he gets these questions all the time , so he sent me a copy of the certificate saying what other oil are also good for 2011 newer GM's and they were not GM DEXOS OIL
PS it's your car do what you want , I run regular in both of mine
PS it's your car do what you want , I run regular in both of mine
Instructor
Joined: Sep 2010
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From: Michigan
When an engine is developed they do a "Knock Test" as part of the normal development, it is part of the mapping process which sets the spark and fuel for the entire range the engine will run and all weather conditions. Temperature, barometer, humidity all enter into the equation besides the air flow, throttle position, RPM and all the other factors tested.
Most times on a performance engine the Knock Sensor is there to pull back spark for those times when and owner can't get premium fuel. Sure the engine will run fine, especially when driven around town and not heavily loaded. Going from part throttle to wide open is also a critical area.
I really don't think this is one of those "Deals" with a gas company.
I would bet that the vast majority of C5 Corvettes are driven pretty easily, when lower octane will work just fine, and not getting the crap beat out of them when you had better have premium fuel.
Most times on a performance engine the Knock Sensor is there to pull back spark for those times when and owner can't get premium fuel. Sure the engine will run fine, especially when driven around town and not heavily loaded. Going from part throttle to wide open is also a critical area.
I really don't think this is one of those "Deals" with a gas company.
I would bet that the vast majority of C5 Corvettes are driven pretty easily, when lower octane will work just fine, and not getting the crap beat out of them when you had better have premium fuel.
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From: Charlotte NORTH CAROLINA
" Constant use of say 87 octane fuel, when in your owners manual it clearly states the car must be run on a fuel with a Octane rating of at least 91 octane. "
I'm not arguing the benefits of running premium. I use it and these discussions go no where from what I've seen but this is not at all what my owners manual says. Mine just says "Use premium unleaded gasoline rated at 91 octane or higher for best performance. You may use middle grade or regular unleaded gasolines, but your vehicle's acceleration may be slightly reduced."
I'm not arguing the benefits of running premium. I use it and these discussions go no where from what I've seen but this is not at all what my owners manual says. Mine just says "Use premium unleaded gasoline rated at 91 octane or higher for best performance. You may use middle grade or regular unleaded gasolines, but your vehicle's acceleration may be slightly reduced."
