I have used mid grade 89 octane on a stickly road trip, but only used shell, chevron or similar. it works for me on long 4500 mile trips ... to each his own however.
Gas ?
Thread Starter
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Joined: Jul 2007
Posts: 60
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From: Independence Ky
Gas ?
Can you really tell a difference in 89 octane (in the gas pedal) or 92 octane? I have a race with my buddy and he drives a 07 Mustang GT (nice car) with a 5 speed trans. I have a 97 C5 auto. No engine MODs on either car, can I bet him?
Le Mans Master
Joined: Dec 2001
Posts: 5,705
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From: St. Peters MO
C7 of Year Finalist (stock) 2019
2018 C7 of Year Finalist
You can use the cheap stuff and the computer will compensate but you won't make all the power it's capable of. Whether you can actually feel the difference, I doubt it. GM recommends 91 octane for an unmodified LS1.
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Race Director
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From: 972 and 405
This was answered in the other thread. Different octane yields different results. That's why the stations offer different octanes, and they cost differently.
As stated before, buy premium for your Corvette. It's not a damn Civic.
-Alex
As stated before, buy premium for your Corvette. It's not a damn Civic.
-Alex
Team Owner
Joined: Aug 2004
Posts: 24,129
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From: The Beautiful Pacific Northwest
St. Jude Donor '05-'06-'07-'08-'09, '14-'15-'16-'17-'18
Why use cheap gas? Get the most out of your car and avoid replacing your fuel gauge...use a Top Tier gasoline.
Tech Contributor
Joined: Dec 2003
Posts: 19,384
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From: Horncastle Lincolnshire, England
2023 C5 of the Year Finalist - Unmodified
The book actually says:
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.
The knock sensor is a reactive device. In other words the damage however minor has occurred when it makes the timing adjustment. Once thats happened as rws1 says, the fuel economy and performance suffer.
E-T who was involved in the design of the C5 had very strong views that with the high compression LS1 you shouldn't use less than 91 octane. Seems sensible to me.
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.
The knock sensor is a reactive device. In other words the damage however minor has occurred when it makes the timing adjustment. Once thats happened as rws1 says, the fuel economy and performance suffer.
E-T who was involved in the design of the C5 had very strong views that with the high compression LS1 you shouldn't use less than 91 octane. Seems sensible to me.
Melting Slicks
Joined: Jul 2005
Posts: 2,572
Likes: 3
From: Rehoboth MA . . . NRA Life Member
St. Jude Donor '06-'07
Hmmmmm, lets see,
Anyone see where I'm going with this?...
- My Z06 cost me a tad over $52,000 when I bought it.
- The manufacturer calls for the use of premium fuel, 91 octane or above.
- The difference between regular and premium is $0.30 more per gallon.
- It costs $5.40 more to fill up from an empty tank.....assuming 18 gallons
Anyone see where I'm going with this?...
Instructor
Joined: May 2005
Posts: 145
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From: Nevada Texas
I didn't
after 1/4 million miles I have had no problems with 87 octane gas, for several years I drove 100 to 150 miles a day to work and back, this is my everyday driver and the gas savings over my blazer (12 mpg) or jeep (14 mpg) helped pay for my vette. I still drive 50 miles a day round trip. Occasionally I put a tank or two of shell premium thru it but for the most part I use murphy 87. I haven't had to do anything to the ls1 other than replace the harmonic balancer. it still gets 27 mpg and does not burn oil. some of us like there vettes even though we may not be rich.
Racer
Joined: Nov 2005
Posts: 404
Likes: 0
From: KY
Just buy 91 or higher. Sure it will run on something lower, but why tempt fate when it's designed for something higher.
And yes you should be able to beat the mustang especially if you have the 3.15 rear end. Mind you it won't be a walk seeing as he's got a 5 speed.
And yes you should be able to beat the mustang especially if you have the 3.15 rear end. Mind you it won't be a walk seeing as he's got a 5 speed.
