Need some quick input. i live in the Seattle area and always fill with Shell, Chevron or 76. My preference has always been Chevron. I saw the Pure-gas website and there are stations in my area that sell fuel with no ethanol in it. These stations are not "top tier". What should I be more worried about? Which is the better way to go if you don't consider cost and only consider what is best for the car.
Top tier or Pure gas
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I would go with the pure gas as long as they were not coming from some station with a rusty pump. I filled my lawn equipment with "pure gas" last week and a weedeater that barely worked is running like a top. My riding mower is running great too. I didn't fill up the car because I was pretty full but knew I would be in the area of that station and brought my cans. It isn't worth me going so far out of the way where I live.
My question is whether the top tier gasoline actually contains any useful levels of additives once it's in your tank. There's really no way to tell how concentrated the detergents or other additives are, is there? That's why I figured I may as well just buy the cheapest gas around, change my fuel filter yearly (something I do anyway), and maybe use some concentrated fuel injector cleaner every other oil change or something. Personally, I would buy the ethanol-free gas. I'm not sure whether your newer vehicles will see any MPG boost from ethanol-free gas, but your '97 Camry likely would.
Originally Posted By: Towncivilian
I'm not sure whether your newer vehicles will see any MPG boost from ethanol-free gas, but your '97 Camry likely would.
I would think every car would see a MPG boost. Ethanol just doesn't have as much energy in it.
I'm not sure whether your newer vehicles will see any MPG boost from ethanol-free gas, but your '97 Camry likely would.
I would think every car would see a MPG boost. Ethanol just doesn't have as much energy in it.
Hi.
Ethanol is an oxygenate that is used in gasoline to reduce emissions by facilitating more complete combustion. The reason why some vehicles may experience decreased performance is because an oxygenate by definition introduces more oxygen into the fuel-air mixture. This shifts our excess air factor (lambda) to the right, forcing a reaction that is what we could term "lean burning." Lean burn is not favored by some vehicles because they are optimized to run a slightly richer (lambda < 0) fuel-air mixture for increased power, better driveability, and lower NOx formation. Of course, this comes at the cost of increased CO and CO2 emissions. A catalytic converter can be used to reduce both of these emissions.
Anyways, Top Tier gasoline has to be certified to obtain that rating. This is at the discretion of a group of automakers. It's a guarantee that you will get high quality gasoline. However, just because it doesn't carry that certification doesn't mean it's not high quality. It's just they do not want to, or have the assets to pursue, that certification.
It's perceived that pure gasoline is better for your engine instead of being oxygenated with ethanol. That's an incorrect assumption. Ethanol increases the enthalpy change of combustion (delta H more negative) of a gasoline mixture. So you get more energy = more power. However, the car's engine has to be able to handle the increased temperatures and energy. Most cars cannot, so it's perceived that ethanol lowers power. Likewise however, most cars also experience lower fuel economy because ethanol typically burns faster. Although it produces more energy. That's the simple answer, but it gets more complex.
Of course there will always be exceptions.
Ethanol is an oxygenate that is used in gasoline to reduce emissions by facilitating more complete combustion. The reason why some vehicles may experience decreased performance is because an oxygenate by definition introduces more oxygen into the fuel-air mixture. This shifts our excess air factor (lambda) to the right, forcing a reaction that is what we could term "lean burning." Lean burn is not favored by some vehicles because they are optimized to run a slightly richer (lambda < 0) fuel-air mixture for increased power, better driveability, and lower NOx formation. Of course, this comes at the cost of increased CO and CO2 emissions. A catalytic converter can be used to reduce both of these emissions.
Anyways, Top Tier gasoline has to be certified to obtain that rating. This is at the discretion of a group of automakers. It's a guarantee that you will get high quality gasoline. However, just because it doesn't carry that certification doesn't mean it's not high quality. It's just they do not want to, or have the assets to pursue, that certification.
It's perceived that pure gasoline is better for your engine instead of being oxygenated with ethanol. That's an incorrect assumption. Ethanol increases the enthalpy change of combustion (delta H more negative) of a gasoline mixture. So you get more energy = more power. However, the car's engine has to be able to handle the increased temperatures and energy. Most cars cannot, so it's perceived that ethanol lowers power. Likewise however, most cars also experience lower fuel economy because ethanol typically burns faster. Although it produces more energy. That's the simple answer, but it gets more complex.
Of course there will always be exceptions.
I agree Towncivilian, there really is no way to tell what is in the "top-tier' fuel you buy. If you run cleaners anyway, why pay the ridiculous prices at chevron when I can pay almost 18 cents less/gal for Sunoco or 7-11? I tried a month of "top-tier" and could not tell a difference in performance or fuel economy, but I could tell I was spending more for gas.
There is no Mom&Pop refineries and there is no bad fuel, all fuel grades must pass Federal standard, the only possible problem is stations with few customers and therefore do not upkeep their equipments/storage tanks. I would buy ethanol-free gas if available, but none in CA.
No contest, go with real gasoline.
Originally Posted By: Towncivilian
My question is whether the top tier gasoline actually contains any useful levels of additives once it's in your tank. There's really no way to tell how concentrated the detergents or other additives are, is there? That's why I figured I may as well just buy the cheapest gas around, change my fuel filter yearly (something I do anyway), and maybe use some concentrated fuel injector cleaner every other oil change or something. Personally, I would buy the ethanol-free gas. I'm not sure whether your newer vehicles will see any MPG boost from ethanol-free gas, but your '97 Camry likely would.
There is definitely a difference.
http://www.toptiergas.com/
My question is whether the top tier gasoline actually contains any useful levels of additives once it's in your tank. There's really no way to tell how concentrated the detergents or other additives are, is there? That's why I figured I may as well just buy the cheapest gas around, change my fuel filter yearly (something I do anyway), and maybe use some concentrated fuel injector cleaner every other oil change or something. Personally, I would buy the ethanol-free gas. I'm not sure whether your newer vehicles will see any MPG boost from ethanol-free gas, but your '97 Camry likely would.
There is definitely a difference.
http://www.toptiergas.com/
Chevron, Shell, and 76 seem like the majority favorites. Do any of you use cheaper brands? Like Arco and Valero?
Originally Posted By: dtt004
Hi.
Likewise however, most cars also experience lower fuel economy because ethanol typically burns faster. Although it produces more energy.
Sorry, have to disagree with your statement that ethanol contains more energy. The BTU's of ethanol are substantially lower than gasoline, something like 6000 BTU's per pound of fuel.
Hi.
Likewise however, most cars also experience lower fuel economy because ethanol typically burns faster. Although it produces more energy.
Sorry, have to disagree with your statement that ethanol contains more energy. The BTU's of ethanol are substantially lower than gasoline, something like 6000 BTU's per pound of fuel.
Originally Posted By: cchase
Originally Posted By: dtt004
Hi.
Likewise however, most cars also experience lower fuel economy because ethanol typically burns faster. Although it produces more energy.
Sorry, have to disagree with your statement that ethanol contains more energy. The BTU's of ethanol are substantially lower than gasoline, something like 6000 BTU's per pound of fuel.
+1 Ethanol has considerably less energy per volume than gasoline.
"Top tier or Pure gas"..... There is no "pure gas" all gasoline has detergents added by government mandate. That is a good thing.
Top Tier has a higher level of detergency than prescribed by the feds. That is a better thing. Top Tier may or may not contain ethanol.
Rickey.
Originally Posted By: dtt004
Hi.
Likewise however, most cars also experience lower fuel economy because ethanol typically burns faster. Although it produces more energy.
Sorry, have to disagree with your statement that ethanol contains more energy. The BTU's of ethanol are substantially lower than gasoline, something like 6000 BTU's per pound of fuel.
+1 Ethanol has considerably less energy per volume than gasoline.
"Top tier or Pure gas"..... There is no "pure gas" all gasoline has detergents added by government mandate. That is a good thing.
Top Tier has a higher level of detergency than prescribed by the feds. That is a better thing. Top Tier may or may not contain ethanol.
Rickey.
Originally Posted By: cchase
Originally Posted By: dtt004
Hi.
Likewise however, most cars also experience lower fuel economy because ethanol typically burns faster. Although it produces more energy.
Sorry, have to disagree with your statement that ethanol contains more energy. The BTU's of ethanol are substantially lower than gasoline, something like 6000 BTU's per pound of fuel.
I agree.
Comment it produces "more energy" is troubling from a physics standpoint.
Originally Posted By: dtt004
Hi.
Likewise however, most cars also experience lower fuel economy because ethanol typically burns faster. Although it produces more energy.
Sorry, have to disagree with your statement that ethanol contains more energy. The BTU's of ethanol are substantially lower than gasoline, something like 6000 BTU's per pound of fuel.
I agree.
Comment it produces "more energy" is troubling from a physics standpoint.
According to fueleconomy.gov, the official U.S. government source for fuel economy information, energy content of ethanol is lower than gasoline. It also said "vehicles will typically go 3–4% fewer miles per gallon on E10 than on straight gasoline."
Energy content of Ethanol is 76,000 BTUs/Gal compares to 114,000 BTUs/Gal for Gasoline.
Energy content of Ethanol is 76,000 BTUs/Gal compares to 114,000 BTUs/Gal for Gasoline.
Also AFAIK, in order to be a "Top Tier" Certified gasoline company all of the grades sold, which is usually 87,89,93 octane in PA must meet the "Top Tier" detergency standards.
If only the "93" octane meets the requirement than the "Top Tier" designation is not given.
Some Sunoco stations still carry the in between grades of 91 and or 94 octane gasoline, but they are rare anymore.
(Remember when Sunoco used to carry 86,87,89,91,93 AND 94 octane?)
Also Valero is/was the largest independent refiner in the United States not associated with any other countries.
I noticed tonight the pumps here all have shiny new stickers " "COMMING JUNE 1 THROUGH WHENEVER IS CLEANER RVP GASOLINE"
........RVP,E10,E15,E85 all a scam IMO.
If only the "93" octane meets the requirement than the "Top Tier" designation is not given.
Some Sunoco stations still carry the in between grades of 91 and or 94 octane gasoline, but they are rare anymore.
(Remember when Sunoco used to carry 86,87,89,91,93 AND 94 octane?)
Also Valero is/was the largest independent refiner in the United States not associated with any other countries.
I noticed tonight the pumps here all have shiny new stickers " "COMMING JUNE 1 THROUGH WHENEVER IS CLEANER RVP GASOLINE"
........RVP,E10,E15,E85 all a scam IMO.
Most of these treads volley between "it doesn't matter - I see no immediate difference" to "I use the best in my car".
Facts:
1. Gasoline leaves carbon behind when it burns. this builds up. Gasoline has had detergents since the 80s by US EPA law. It is a function of miles, but also load.
2. The EPA minimums are not adequate for maintaining a clean engine over a long period of time. How long? Depends. Rule of thumb is 100k.
3. If you trade cars regularly (50k), you will not likely notice the benefits, nor downsides of extra or inadequate additives.
4. If you keep a car a long time, these problems creep up and have symptoms that seem like other issues like emission controls or tuning, resulting in erratic driveability.
5. Top tier gasoline has between 2x to 5x the detergency of the EPA requirements. This is the main difference. 2x will keep clean, 5x removes old gunk. 5x is not needed long term, if used regularly. the brands do not disclose regularly how much they have in their brand.
6. The base gasoline is generic and a commodity. it is the additives that matter.
You decide how long you want to keep your car vs. the benefits.
Facts:
1. Gasoline leaves carbon behind when it burns. this builds up. Gasoline has had detergents since the 80s by US EPA law. It is a function of miles, but also load.
2. The EPA minimums are not adequate for maintaining a clean engine over a long period of time. How long? Depends. Rule of thumb is 100k.
3. If you trade cars regularly (50k), you will not likely notice the benefits, nor downsides of extra or inadequate additives.
4. If you keep a car a long time, these problems creep up and have symptoms that seem like other issues like emission controls or tuning, resulting in erratic driveability.
5. Top tier gasoline has between 2x to 5x the detergency of the EPA requirements. This is the main difference. 2x will keep clean, 5x removes old gunk. 5x is not needed long term, if used regularly. the brands do not disclose regularly how much they have in their brand.
6. The base gasoline is generic and a commodity. it is the additives that matter.
You decide how long you want to keep your car vs. the benefits.
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