Premium Gas?
CF JASOC Member
Joined: Feb 2006
Posts: 8,040
Likes: 34
From: Downtown Annapolis, MD. The Future is where we all have to live. Let's not screw it up.
St. Jude Donor '08-'09-'10-'11
My first REAL job was at a Sunoco station in '76.
The lowest grade and highest grade fuels were actually mixed by valves in the pump to formulate the mid grades. There were like 6 choices?
Mark
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
Yes, it's no different today. Mid grade (89 octane) is a mixture of 87 and 91 done inside the pump.
Drifting
Joined: Aug 2009
Posts: 1,635
Likes: 8
From: Enid Oklahoma
Higher octant does ZERO to "clean" anything ever. If you run too high of octane just because, it will carbon up, too low and it will predetonate and run lean. Most stock lower compression C3s should run just fine on 87. If you are forced to use high octane be sure to run Seafoam or its equivelant periodically to keep carbon buildup down. Ocatne is the number that tells you at what point under pressure the fuel will spontaneouly ignite. The higher the compression the higher the octane to keep predetonation away. Timing plays a part as well in the equation. I run 87 no Ethanol fuel.
Last edited by 81pilot; May 12, 2012 at 06:11 PM.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
I'm interested in knowing what "burning clean" means? Is the alternative to that [meaning, using lower octane fuel] "burning dirty"? And, if so, what gets 'dirty'? 
P.S. My L-48 engine has 209K miles on it. As far as I know, it has never seen anything but "regular" fuel; the owner's manual recommends 'regular unleaded fuel', anyway. When I pulled the heads for a [lightly] blown head gasket 2 years ago, the pistons were marked for .040"-over and there was almost no ridge at the top of the cylinder walls. I use the GM recommended plugs and they show just a light-tan color when I check them. So, why do I 'need' premium gas?
P.S. My L-48 engine has 209K miles on it. As far as I know, it has never seen anything but "regular" fuel; the owner's manual recommends 'regular unleaded fuel', anyway. When I pulled the heads for a [lightly] blown head gasket 2 years ago, the pistons were marked for .040"-over and there was almost no ridge at the top of the cylinder walls. I use the GM recommended plugs and they show just a light-tan color when I check them. So, why do I 'need' premium gas?
Last edited by 7T1vette; May 12, 2012 at 06:59 PM.
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
Higher octant does ZERO to "clean" anything ever. If you run too high of octane just because, it will carbon up, too low and it will predetonate and run lean. Most stock lower compression C3s should run just fine on 87. If you are forced to use high octane be sure to run Seafoam or its equivelant periodically to keep carbon buildup down. Ocatne is the number that tells you at what point under pressure the fuel will spontaneouly ignite. The higher the compression the higher the octane to keep predetonation away. Timing plays a part as well in the equation. I run 87 no Ethanol fuel.
Racer
Joined: Nov 2008
Posts: 442
Likes: 6
From: jacksonville Florida
now tell me this why is it more expensive to put non-ethanol gas in my car? because the gas station can get away with it basically?
just in case you wanna find your own ethanol free gas http://pure-gas.org/index.jsp?stateprov=FL
just in case you wanna find your own ethanol free gas http://pure-gas.org/index.jsp?stateprov=FL
Last edited by pleasants9; May 12, 2012 at 07:17 PM.
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Melting Slicks
Joined: Jan 2012
Posts: 3,033
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From: myrtle beach sc
Army
XCCTER, I worked at my buddies Sunoco station for 3 1/2 months and he showed me that they had only two tanks of fuel ( one 260 tank and one 180 I believe) and two pumps, one for each tank. That is how the fuel was mixed, by the two pumps speed. No valves were involved. Actually, it was two pumps in each "pump" with the dispensing hose.
Last edited by loup68; May 13, 2012 at 03:55 PM. Reason: added text.
Race Director
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From: Danville Illinois
2025 Corvette of the Year Finalist - Modified
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I run regular in all the cars, no problems.
Burning Brakes
Joined: May 2009
Posts: 1,232
Likes: 6
From: Tucson AZ
St. Jude Donor '12
Higher octant does ZERO to "clean" anything ever. If you run too high of octane just because, it will carbon up, too low and it will predetonate and run lean. Most stock lower compression C3s should run just fine on 87. If you are forced to use high octane be sure to run Seafoam or its equivelant periodically to keep carbon buildup down. Ocatne is the number that tells you at what point under pressure the fuel will spontaneouly ignite. The higher the compression the higher the octane to keep predetonation away. Timing plays a part as well in the equation. I run 87 no Ethanol fuel.
(tongue firmly in cheek).
Last edited by RobbSalzmann; Jun 15, 2012 at 07:29 PM.
Melting Slicks
Joined: Apr 2001
Posts: 3,399
Likes: 278
From: Olmsted Falls, Ohio
75 L82 S/R Torquer heads, Holley 670 S/A, about 9 comp thru true dual exhaust.
I usually run 89, sometimes 93 BUT NEVER ANYTHING WITH ETHANOL because the engine will chug and knock with that crap.
My 2007 & 2012 Chevs don't care, the computer takes care of it, and they are designed to run on the EPAs current brew.
I usually run 89, sometimes 93 BUT NEVER ANYTHING WITH ETHANOL because the engine will chug and knock with that crap.
My 2007 & 2012 Chevs don't care, the computer takes care of it, and they are designed to run on the EPAs current brew.
Melting Slicks
Joined: Apr 2001
Posts: 3,399
Likes: 278
From: Olmsted Falls, Ohio
Pro
Joined: Feb 2000
Posts: 741
Likes: 46
From: Hebron IN
I've also ran my air cooled 66 Corvair for decades off of it as well as my 1962 Olds with its original 394 Ultra High Compression rocket engine. Neither had any issues with knocking or chugging.
Even the rancid smelling oxygenated gas that appeared in my area in the mid 90s has never given me a single issue in anything from my big V8s to my weed-eater engine.
When traveling well out of my area where ethanol free gas is available, the only difference I notice is a slight increase in mileage.
Racer
Joined: Nov 2008
Posts: 442
Likes: 6
From: jacksonville Florida
I'm not saying its too expensive to afford or anything, I was just commenting. All gas is too expensive...lol I'm really hoping the electric car infrastructure or hydrogen engines pull through
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
My engines have run just fine on 10% ethanol for over 30 years. My 75 spent its entire life in my area and started getting 10% ethanol in the LATE 70s and never had a single issue with it. Ethanol is not some new phenomenon sweeping the country and killing engines....it's been the only choice in some emission controlled areas for DECADES.
I've also ran my air cooled 66 Corvair for decades off of it as well as my 1962 Olds with its original 394 Ultra High Compression rocket engine. Neither had any issues with knocking or chugging.
Even the rancid smelling oxygenated gas that appeared in my area in the mid 90s has never given me a single issue in anything from my big V8s to my weed-eater engine.
When traveling well out of my area where ethanol free gas is available, the only difference I notice is a slight increase in mileage.
I've also ran my air cooled 66 Corvair for decades off of it as well as my 1962 Olds with its original 394 Ultra High Compression rocket engine. Neither had any issues with knocking or chugging.
Even the rancid smelling oxygenated gas that appeared in my area in the mid 90s has never given me a single issue in anything from my big V8s to my weed-eater engine.
When traveling well out of my area where ethanol free gas is available, the only difference I notice is a slight increase in mileage.
Although I can't say I've seen a definite change in mileage- the 3% difference between E10 and pure gas is pretty hard to track reliably.
Instructor
Joined: Jan 2012
Posts: 201
Likes: 6
From: Atlanta Georgia
Actually...
http://www.examiner.com/article/etha...-and-emissions
http://www.nytimes.com/2009/05/10/au...ANOL.html?_r=1
The big 3 are all working on engines that run better with ethanol, and they are FINALLY really getting here. But for older cars? There is very little to suggest it's good for them.
Places like Sears are actually not covering damage to the fuel systems of their gas-powered tools due to the number of problems.
The manual suggests 90 for my car, if I recall correctly. Everything here is either 89 or 91, so I run the 91. And yes, I understand that the evolution of fuel over the past 20 years means that an 89 octane is less likely to diesel, etc, but eh. I can afford $100 a year for the peace of mind that there are no subsonic knocks screwing with my timing.
