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Old Jan 9, 2021 | 11:29 AM
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Not sure what im doing, im a new member. Is anyone reading this? I just purchased a 1989 Corvette convertible. I filled with regular unleaded, was this wrong?
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Old Jan 9, 2021 | 11:33 AM
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You should use the high octane unleaded gas in your car, but a tank of regular will not hurt it in any way. Show us some pictures of your car and welcome to the fraternity.
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Old Jan 9, 2021 | 11:39 AM
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It probably won't hurt it, but you won't get the performance you should out of it.
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Old Jan 9, 2021 | 12:01 PM
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Gas in a diesel engine, catastrophic. Diesel in a gas engine a lot of clean up. Regular in an engine that requires premium not so bad, maybe a bit of a knock.
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Old Jan 9, 2021 | 12:07 PM
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Originally Posted by Robert Hampton
Not sure what im doing, im a new member. Is anyone reading this? I just purchased a 1989 Corvette convertible. I filled with regular unleaded, was this wrong?
The 1989 owners manual says use 91 octane, but a tank of regular is no big deal
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Old Jan 9, 2021 | 01:16 PM
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I had 1989 L98 engine, and when gas went through the ceiling I ran regular and never hurt anything.
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Old Jan 9, 2021 | 02:20 PM
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Welcome to the Forum and congrats on your new '89 Vette vert.

What colors, stick or auto, any pics of it?
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Old Jan 9, 2021 | 02:21 PM
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Some people say unleaded is fine and has the same detergents and whatnot, others say that premium ignites too fast. I've seen all sorts of arguments for and against regular unleaded and just as many arguments for or against premium. Just depends who youre talking to, I supposse.

All I know is that I never really catch a break when the price of gas drops. Not really. This past summer when gas prices dropped the majority of Americans were celebrating 99 cent regular unleaded.

I was still paying $3.29 for premium.
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Old Jan 11, 2021 | 12:31 PM
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Ethanol is a whole different conversation. Do not use! The ECM simply isn't programmed to correct for it. Some also argue that ethanol will ruin some seals, etc. can't vouch for that.

I made the mistake of dumping a tank of 91 ethanol in my '87 the first year, big mistake and took an evening to drain all that out.
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Old Jan 11, 2021 | 12:32 PM
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Originally Posted by kael
Ethanol is a whole different conversation. Do not use! The ECM simply isn't programmed to correct for it. Some also argue that ethanol will ruin some seals, etc. can't vouch for that.

I made the mistake of dumping a tank of 91 ethanol in my '87 the first year, big mistake and took an evening to drain all that out.
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Old Jan 11, 2021 | 03:04 PM
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I get that ethanol is bad but don't most all gases have it. Does premium not contain it?
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Old Jan 11, 2021 | 03:08 PM
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Originally Posted by Natty C
Some people say unleaded is fine and has the same detergents and whatnot, others say that premium ignites too fast. I've seen all sorts of arguments for and against regular unleaded and just as many arguments for or against premium. Just depends who youre talking to, I supposse.

All I know is that I never really catch a break when the price of gas drops. Not really. This past summer when gas prices dropped the majority of Americans were celebrating 99 cent regular unleaded.

I was still paying $3.29 for premium.
Premium is unleaded
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Old Jan 11, 2021 | 03:09 PM
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Originally Posted by kael
Ethanol is a whole different conversation. Do not use! The ECM simply isn't programmed to correct for it. Some also argue that ethanol will ruin some seals, etc. can't vouch for that.

I made the mistake of dumping a tank of 91 ethanol in my '87 the first year, big mistake and took an evening to drain all that out.
You wasted your time
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Old Jan 18, 2021 | 01:11 AM
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Originally Posted by Cruisinfanatic
You wasted your time
Oh yeah, putting that corn crap in and then having Her stagger home after that crap hit the fuel rail, yep, big waste of time.

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Old Jan 18, 2021 | 06:38 AM
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The only cars we put regular in is our 16 Wrangler, 14 Cherokee and 12 Compass. Our 05 Cobalt and older cars get non-ethanol premium. Needless to say when premium was around $5.00/gallon they weren't driven very much.
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Old Jan 18, 2021 | 08:35 AM
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Originally Posted by kael
Oh yeah, putting that corn crap in and then having Her stagger home after that crap hit the fuel rail, yep, big waste of time.

Geez, thousands use it every day and none limp home. Impossible in a lot of places to find ethonal free fuel
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Old Jan 18, 2021 | 08:36 AM
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Originally Posted by Beater12
I get that ethanol is bad but don't most all gases have it. Does premium not contain it?
Exactly. All gas has it unless you can find someplace that sells ethenol free.

Last edited by Cruisinfanatic; Jan 18, 2021 at 08:37 AM.
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Old Jan 18, 2021 | 08:43 AM
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Congrats Robert
I have an 89 convertible as well
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Old Jan 22, 2021 | 01:59 AM
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...others say that premium ignites too fast.
Premium ignites/burns slower, actually. That's why it's recommended in high compression engines.

Ethanol does reduce power and so fuel economy a tad because alcohol has less energy denisty than gasoline.
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Old Jan 22, 2021 | 09:12 AM
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Originally Posted by Natty C
Some people say unleaded is fine and has the same detergents and whatnot, others say that premium ignites too fast. I've seen all sorts of arguments for and against regular unleaded and just as many arguments for or against premium. Just depends who youre talking to, I supposse.

All I know is that I never really catch a break when the price of gas drops. Not really. This past summer when gas prices dropped the majority of Americans were celebrating 99 cent regular unleaded.

I was still paying $3.29 for premium.
You should move. Sounds like you live in a place where your politicians have betrayed you.

Side note, premium doesn't ignore faster. In fact, it's the opposite, that's why you don't get knock as bad with it.

OP, I wouldn't make a habit out of it, but it's fine. Throw a bottle of octane booster in this tank and it'll give you piece of mind.
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