Fuel question
Thread Starter
Le Mans Master
Joined: May 2009
Posts: 5,093
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From: WV
Fuel question
Finally we have a station in my area that has ethanol free gas. The problem is it’s only 87. Would it be better to keep running 93 with ethanol or use an octane booster with non ethanol?
cars are 03 z06, 66 327/300 and a 60 with a 350 in it. Might be a stupid question but it can’t hurt to ask.
cars are 03 z06, 66 327/300 and a 60 with a 350 in it. Might be a stupid question but it can’t hurt to ask.
Racer
Joined: May 2021
Posts: 259
Likes: 73
From: Mississippi
Find a local airport and buy 100LL. I use 100LL (Low Lead) in my "66 327/350hp car and it runs great. I run it straight at time and also mix it with 90 Octane from a local gas station without any issues. Recently paid $5.20 a gallon, just remember the airport will not let you pump it directly in any vehicle (legally) but you can pump it in a gas can without any legal issues. However 100LL can not be used in modern vehicle with catalytic converters as it will plug them up with the lead in the fuel. A lot of the Octane boost additives out there on most local shelves aren't as them seem and you'll spend a lot of money buying enough of it to obtain the desired Octane. 100LL is a more stable fuel and will provide better Hot (engine) car starts just to name one positive aspect. Good luck
Race Director
Joined: Feb 2007
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From: northern california
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Finally we have a station in my area that has ethanol free gas. The problem is it’s only 87. Would it be better to keep running 93 with ethanol or use an octane booster with non ethanol?
cars are 03 z06, 66 327/300 and a 60 with a 350 in it. Might be a stupid question but it can’t hurt to ask.
cars are 03 z06, 66 327/300 and a 60 with a 350 in it. Might be a stupid question but it can’t hurt to ask.
If you car is running fine on your 93 octane E10, I can't think of a reason you should switch to anything else.
Team Owner
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From: Sitting in his Nowhere land Hanover Pa
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beside the fact I use PA ethanol laced gas and so does my dad in all his cars with no ill effects I can't see why you need to switch
Melting Slicks
Joined: Sep 2005
Posts: 2,702
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From: Warminster PA
I run 93 in my Z06 and 89 or 91 in the other cars which all have lower compression then the Z06. I only use TopTier fuel in the cars including my daily drivers. Local Shell station is where I usually go.
On that note, I recently had the carb apart on my 60. First time in probably 10 years - clean as a whistle inside. Based on all of the bad publicity you read on the internet about the ethanol fuels, I was expecting the worst. I was pleasantly surprised.
Tom
On that note, I recently had the carb apart on my 60. First time in probably 10 years - clean as a whistle inside. Based on all of the bad publicity you read on the internet about the ethanol fuels, I was expecting the worst. I was pleasantly surprised.
Tom
Racer
Joined: Dec 2005
Posts: 387
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From: Seattle
My story about ethanol fuel is different. After buying my 57 (Chevrolet car) with a Rochester FI on it the previous owner had run ethanol fuel in for years. The fuel tank had major rust in it that had worked its way through the fuel delivery system. A major overhaul and replacement of parts from the gas cap to injector nozzles was required. I will never run ethanol gas in my FI cars.
About 100LL avgas, yes I use it from my local airport, it has some good aromatics in it that reduce vapor issues and the shelf life is very good. Acquiringly it can be tricky to acquire as airports have been tasked with insuring that it is used for aviation and not road usage. So, I can access it after hours when the fuel ***** are gone or taxi my airplane to the pumps with 5 gallon cans in the baggage compartment. Either way this gas is great with high octane and good shelf life and no ethanol... Al
About 100LL avgas, yes I use it from my local airport, it has some good aromatics in it that reduce vapor issues and the shelf life is very good. Acquiringly it can be tricky to acquire as airports have been tasked with insuring that it is used for aviation and not road usage. So, I can access it after hours when the fuel ***** are gone or taxi my airplane to the pumps with 5 gallon cans in the baggage compartment. Either way this gas is great with high octane and good shelf life and no ethanol... Al
Race Director
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The first consideration is you need enough octane to keep the engine out of detonation. For your '03 follow GM's recommendation in the owner's manual. Your '66 327/300 required "premium" when new, but if it was rebuilt with lower compression it may tolerate 87. You have to test, and the same applies to the 350 in the '60.
If the cars are normally kept in an non-condensing humidity environment, like a garage, and you drive them enough to consume at least a full tank of fuel in a year, ethanol will likely not cause problems.
Duke
If the cars are normally kept in an non-condensing humidity environment, like a garage, and you drive them enough to consume at least a full tank of fuel in a year, ethanol will likely not cause problems.
Duke
Last edited by SWCDuke; Oct 23, 2021 at 11:04 AM.
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Racer
Joined: May 2021
Posts: 259
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From: Mississippi
To each their own, but if your car is not a daily driver and more of a seasonal driven car like a lot of classic cars are then your playing with fire using ethanol fuels. Ethanol absorbs water and that is not good for fuel system in the long run. I'm not saying your lines or tanks will rust out tomorrow but it will eventually cause issues for stored vehicles. I personally like to eliminate problems before they happen instead of being reactive and my choice is non-ethanol for my vehicles, boats, etc that are not driven or used regularly. I recently replace my fuel line fuel line that was rusted out on my 1966 327/350 car and most know that requires removing the body to do it properly and I don't care to do that again.
Burning Brakes
Joined: Aug 2013
Posts: 1,071
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From: palm springs ca
Find a local airport and buy 100LL. I use 100LL (Low Lead) in my "66 327/350hp car and it runs great. I run it straight at time and also mix it with 90 Octane from a local gas station without any issues. Recently paid $5.20 a gallon, just remember the airport will not let you pump it directly in any vehicle (legally) but you can pump it in a gas can without any legal issues. However 100LL can not be used in modern vehicle with catalytic converters as it will plug them up with the lead in the fuel. A lot of the Octane boost additives out there on most local shelves aren't as them seem and you'll spend a lot of money buying enough of it to obtain the desired Octane. 100LL is a more stable fuel and will provide better Hot (engine) car starts just to name one positive aspect. Good luck
Dom
Pro
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From: Carlisle Pa.
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I use 50% ethanol free with 50% 100 octane av gas in my 57 FI car and premium pump gas in my 02 Z06.
This application seems to work well for me.
This application seems to work well for me.
Pro
Joined: Oct 2013
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From: Lower Jefferson
C2 of the Year Finalist - Modified 2020
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I run 91 pump gas with my 10.5 compression engine. For my LS 7 I mix 1 gal 100 UNLEADED to 3 gal pump 91. That makes 93. I get the 100 at one of two nearby racetracks. It ain’t cheap but no foul in Kommiefornia.
Burning Brakes
Joined: Aug 2021
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From: NH
I run 93 in my Z06 and 89 or 91 in the other cars which all have lower compression then the Z06. I only use TopTier fuel in the cars including my daily drivers. Local Shell station is where I usually go.
On that note, I recently had the carb apart on my 60. First time in probably 10 years - clean as a whistle inside. Based on all of the bad publicity you read on the internet about the ethanol fuels, I was expecting the worst. I was pleasantly surprised.
Tom
On that note, I recently had the carb apart on my 60. First time in probably 10 years - clean as a whistle inside. Based on all of the bad publicity you read on the internet about the ethanol fuels, I was expecting the worst. I was pleasantly surprised.
Tom
Burning Brakes
Joined: Mar 2021
Posts: 998
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From: Tyrone, GA
My retirement hobby is the restoration of old John Deere garden tractors. The biggest problem I have is with the carburetors and Ethanol goo in them. These older tractors sit a lot during the winter months and the Ethanol turns aluminum and rubber into a mess. I drive my car about two or three times a week but during the winter it will be much less. I have seen that my local gas station hasn't had any Ethanol-free fuel for about two weeks. I'm running E-10 now but for the winter months as I tell all of my customers, NEVER store your machine with E-10 in the tank/carb. I will put Ethanol-free in the tank for the winter. E-10 is an ok fuel if it is used daily but for storage or seldom use, it is toxic.
Drifting
Joined: Dec 2009
Posts: 1,394
Likes: 247
From: CT
I'm not trying to bring this thread in a different direction but do the ethanol gas treatments help with these problems?
I always put a couple of ounces in every fill up.
I have no way to guage it helps other than I have had no obvious problems.
I always put a couple of ounces in every fill up.
I have no way to guage it helps other than I have had no obvious problems.
Last edited by Audiophobe; Oct 24, 2021 at 02:53 PM.
Melting Slicks
Joined: Sep 2005
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From: Warminster PA
Had your car sat for any period of time? That is the biggest problem with E10 - it really gums up carbs if allowed to sit (not good for rubber either). I just rebuilt my AFB after it sat with minimal use (but was started monthly) for 2 years. It was terrible. I now add 1 oz of ATF per gallon. Too soon to report results, but others swear by it.
Tom
Melting Slicks
Joined: Mar 2010
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From: DC Metro
DC Area Events Coordinator
I have 93 octane pure gas ~1 hour from my home. That pure gas plus Avgas (101LL) or Octane Supreme gives me the best results. I avoid using any gas with ethanol, particularly so when fall arrives and sitting a few months over winter becomes likely.
http://www.wildbillscorvette.com/octanesupreme01.htm
Helpful... https://www.pure-gas.org/extensions/maps.jsp
http://www.wildbillscorvette.com/octanesupreme01.htm
Helpful... https://www.pure-gas.org/extensions/maps.jsp
Last edited by jb_va2001; Oct 26, 2021 at 12:53 PM.
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Le Mans Master
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I used Stable religiously for 20 years. Never a problem come spring. Then a know-it-all said Stable is Kerosene with some coloring and works by putting an oil slick skin on top of the fuel to prevent it from evaporating. Kind of like the plumber's advice to put a few drops of cooking oil in a the drain of an infrequently used sink.
So that season I skipped it in enlightened protest. That Spring the Impala's 20 year old 4GC needed a go-through and the Corvette was recalcitrant at its first start but fine since.
So I went back to it, but it's probably voodoo or the same reason I still pick up pennies.
Dan
So that season I skipped it in enlightened protest. That Spring the Impala's 20 year old 4GC needed a go-through and the Corvette was recalcitrant at its first start but fine since.
So I went back to it, but it's probably voodoo or the same reason I still pick up pennies.
Dan