Best octane level
05-23-2018, 03:03 PM
#5
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Welcome to the forum, Andrea!
From your owners manual:
“Fuel - Gasoline Octane Use premium unleaded gasoline with a posted octane of 91 or higher for best performance. You may also use middle grade or regular unleaded gasoline rated at 87 octane or higher, but your vehicle’s acceleration may be slightly reduced. If the octane is less than 87, you may get a heavy knocking noise when you drive. If it is bad enough, it can damage your engine.”
So as others have suggested either 93 octane (or 91 octane if 93 is not available) is best.
Shopping around may find you dealers with 93 octane fuel with no ethanol. If so, that's ideal.
Also, if you don't have a copy of the owner's manual for your car, simply google "Owners manual, 2002 Corvette" and you should multiple sites where you can download and save to your computer the manual.
Best wishes with your Corvette!
From your owners manual:
“Fuel - Gasoline Octane Use premium unleaded gasoline with a posted octane of 91 or higher for best performance. You may also use middle grade or regular unleaded gasoline rated at 87 octane or higher, but your vehicle’s acceleration may be slightly reduced. If the octane is less than 87, you may get a heavy knocking noise when you drive. If it is bad enough, it can damage your engine.”
So as others have suggested either 93 octane (or 91 octane if 93 is not available) is best.
Shopping around may find you dealers with 93 octane fuel with no ethanol. If so, that's ideal.
Also, if you don't have a copy of the owner's manual for your car, simply google "Owners manual, 2002 Corvette" and you should multiple sites where you can download and save to your computer the manual.
Best wishes with your Corvette!
05-23-2018, 03:31 PM
#6
Team Owner
Whatever the rating of Premium gas is in your area/state. Not all states will have the same octane gas. Here in WA, we have 92 octane, CA has 91, and you can find 94 octane in British Columbia. I think that 91 octane is the most common in the US.The car's computer should be able to adjust to handle even 89 octane mid-grade gas.
05-23-2018, 03:50 PM
#8
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91 octane is perfect for a stock C5. I run my modified C5 on 93 octane.
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jjc508520 (05-24-2018)
05-23-2018, 06:07 PM
#9
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05-23-2018, 06:28 PM
#10
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I run 94 in my Z, had it tuned for 93. But I'm sure 91 will do.
I would probably run 94 if I had a base model, who knows...
I would probably run 94 if I had a base model, who knows...
05-23-2018, 06:54 PM
#11
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use the highest available at the pump... ethanol will actually raise octane if used in high enough concentration, 10% is not going to make much difference either way so if that's all you have don't worry about it
Last edited by neutron82; 05-23-2018 at 06:55 PM.
05-24-2018, 09:12 PM
#14
Melting Slicks
I've always used 87 to 91. That's all we can get out here. I'm at 5500 ft. so 87 works fine. I usually use 91, though. The way prices are going through the roof it might be 89 next fill up!
05-24-2018, 09:20 PM
#15
Safety Car
At least 91, 93 if you can get it.
And the non-ethanol thing isn't that important for a daily driven C5 (or anything from the late 1990's on). If you store the thing with fuel in the tank and in the fuel system, try to run it near empty first, then fill with non-ethanol before storing. The big issues with ethanol for these engines come during long term storage with fuel with 10% ethanol in the system.
And the non-ethanol thing isn't that important for a daily driven C5 (or anything from the late 1990's on). If you store the thing with fuel in the tank and in the fuel system, try to run it near empty first, then fill with non-ethanol before storing. The big issues with ethanol for these engines come during long term storage with fuel with 10% ethanol in the system.