93 octane
- Thread starter dawgdr93
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rbryce
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Here is an article I read, and I found it to be really good. It seems to cover practically all bases about octane, where it comes from, how it can be modified, what your engine needs and why, and how modern engines can adjust while the older ones cannot. Hope this helps.
The model isn't bad either!
Corvette Fuel Octane - Burning Questions
There are two major elements that bring the Corvette mystique to life. First is power. Power animates the drivetrain and gets your Corvette moving so you can enjoy the thrust and handling enhancements you've made. The other important engine-related element is fuel. No fuel means no go. Engine power is influenced by engine parameters such as induction-system design, combustion-chamber configuration, and exhaust. As a result of the Corvette engine's high-performance demands, not just any gasoline will do. The fuel you use should be tailored to match the power demands, so the engine can deliver maximum power throughout the rpm range. The most obvious topic of discussion concerning fuel demands is octane rating.
To learn more about octane basics, we interviewed Art Brown, technical operations manager at Sunoco Racing Fuels.
Simply stated, octane is a measure of a gasoline's antiknock quality or a fuel's resistance to pre-ignition or detonation. Pre-ignition occurs when the Air/Fuel (A/F) mixture is ignited before the spark occurs. Detonation is, by definition, A/F ignition at some location in the combustion chamber away from the plug. The higher the octane number, the higher a fuel's resistance to unintended combustion. Contrary to urban legend, octane isn't a measure of how fast fuel burns.
An engine's octane requirement is directly related to the engine's compression ratio, which is the ratio between the cylinder volume when the piston is at Bottom Dead Center (BDC) and when it's at Top Dead Center (TDC). If the volume at BDC is 1,000 cc, and at TDC it's 100 cc, the ratio would be 10:1. Mechanical items that can influence compression ratio are piston-to-deck clearance, piston dish, dome shape, head-gasket thickness, and combustion-chamber volume.
Compression is important for increasing power in naturally aspirated engines. When A/F is squeezed more tightly together, increased cylinder pressure results after ignition to create additional push on the piston during the power stroke. As the piston rises, the A/F mixture is compressed, which adds heat. If there is a hot spot in the combustion chamber, the mixture could be ignited prematurely before the spark plug fires. So, higher octane is the way pre-ignition or detonation can be controlled during the compression cycle.
An important concept to understand is that combustion is not an explosion. Ideally, it is a flame wave, initiated by the spark, which burns across the combustion chamber. This smooth burning generates the rapid rise in cylinder pressure during the power stroke.
Knock is the negative result when combustion occurs somewhere else in the cylinder, in addition to the plug. Like the spark-plug-initiated flame wave, the second wave expands so a collision between the wave fronts occurs. This collision produces a radical spike in cylinder pressure. Instead of a firm, even push down on the piston, the pressure spike hammers it down. This is strong enough that it can ultimately burn a piston, crack a piston ring or ring land, or a spark-plug electrode. These excessive pressure spikes can damage even engine bearings. When you hear a metallic rattle while driving, that is the sound of detonation and, in most cases, the cure is fuel with the correct octane.
No doubt, you've seen the "RON plus MON divided by 2" formula posted on fuel pumps. As Brown explains, there is the Research Octane Number (RON) and Motor Octane Number (MON). Together, this is the Anti-Knock Index (AKI). RON utilizes a single-cylinder, laboratory test engine running at 600 rpm with an 83-degree F. intake temperature. MON, on the other hand, utilizes a 900-rpm limit and a 300-degree intake temperature. Test data from these engines allows octane to be determined. Because the AKI is an average, you can have very different fuels produce the same AKI. A fuel with a 120 RON octane and a fuel with a MON 102 octane will deliver the same octane number as one with a 113 RON octane and a MON of 109. By blending different fuels, Sunoco can create a cost-effective gasoline with the desired octane.
Knock control was originally accomplished by adding tetraethyl lead. According to Brown, lead was the standard octane booster. He explains, "It does not bind with gasoline, but rather mixes with it." Using lead was a cheap and easy way to boost octane since all you had to do was pour and mix it in. Until the phase-out of lead starting in 1974 (due to toxic lead emissions), it was easy to get enough octane for your Corvette's engine.
Over the past 25 years, compression ratios have climbed back up, thanks to a combination of refined combustion-chamber design characteristics and engine control electronics. Today you can increase compression and power, but remain detonation free with unleaded 92-octane fuel.
Today, Sunoco blends selected fuel stocks in order to achieve a desired octane rating, in addition to meeting EPA-mandated requirements for oxygenates and emissions-reducing formulation. "We formulate fuels with gasoline components as well as oxygenated components and blend them to 100 octane," Brown explains. "You're limited in the amount of octane you can acquire at a reasonable price through the use of hydrocarbon components and oxygenates. This limit is about 104 octane."
There are also mechanical items that can influence an engine's octane requirement. One aspect is combustion-chamber design. Design reflects on how the A/F mixture behaves in the combustion chamber. Early '60s chamber designs often were a closed style. Today's aftermarket heads, depending on the application, often have more open configurations that promote efficient combustion help, contributing to reduced octane sensitivity.
In addition to mechanical considerations, octane requirements in modern Corvettes are influenced by the sophisticated engine control electronics. Today, an LS6 engine with a 10.5:1 compression ratio, and the former ZR-1 with 11:1 compression, will operate on 92-octane unleaded premium. "How that is able to happen is through the engine management computer," Brown says. "It simply takes more timing out of the engine. What we have found is, if you used GT Unleaded (100-octane), that would allow the computer to put more timing back into the engine and you would see an increase in performance, everything else being equal."
To sum up, if you have a new or nearly new Corvette, use the octane grade recommended in your owner's manual. If your older street-driven Corvette has an original high-compression engine, or you've rebuilt it that way, start with Sunoco's 100-octane GT Unleaded premium to make sure there is no detonation. If it's OK there, blend in a 50/50 mix of 94-octane Ultra, and see if knock occurs. When there is none, that's the lowest octane your engine is happy with. Remember, using a higher octane fuel than what your engine needs only costs you more money.
Here's a selection of compression ratios used in Corvette engines over the decades, with the ZL-1 being the ultimate. This was a thinly disguised race engine and required 100-octane fuel, minimum. Note that compression has slowly crept up over time. The reason compression can increase today, yet still use unleaded 92-octane, lies in the refined combustion-chamber configurations and sophisticated engine electronic controls. Also note that the increased compression contributes to increased power, but it is not the sole reason for the power increase.
Year Engine/Cubic
Inches or Liters CR HP '53 235ci 8.0:1 150 '58 Base/283 9.5:1 230 '69 ZL-1/427 12.5:1 435 '70 LT-1/350 11:1 370 '80 L48/350 8.2:1 190 L82/350 9.0:1 230 LG4/305 8.5:1 180 '90 Base/5.7L 9.5:1 245 ZR-1/5.7L 11.0:1 370 '00 LS1/5.7L 10.1:1 345 '03 LS1/ 5.7L 10.1:1 345 LS6/5.7L 10.5:1 405
If you don't know an engine's compression, you need to measure the elements that determine the compression ratio in order to calculate it. There are mathematical formulas to do it manually, but we have discovered an online compression-ratio calculator.
At the Ross Racing Pistons Web site (www.rosspistons.com), there is a c.r. calculator, where you need only to type in the numbers, and, with a click of the mouse, get your answer. Here's an explanation of the factors, and where to find your specifications.
Bore: In inches
Stroke: In inches
Head volume: This is the combustion-chamber volume in cc's. Head manufacturers have these figures listed in their specs. If you're working with a factory head, or one that's been milled, you will have to measure the volume.
Gasket thickness: In thousandths of an inch. Gasket manufacturers will have this specification.
Deck clearance: In inches. Typically, at top dead center, the piston top is located slightly below the block-deck surface. Your machine shop can give you the dimension.
Piston dish or dome volume: In cc's. A dish increases volume, while a dome decreases it. These specifications are available from the piston manufacturer.
The model isn't bad either!
Corvette Fuel Octane - Burning Questions
There are two major elements that bring the Corvette mystique to life. First is power. Power animates the drivetrain and gets your Corvette moving so you can enjoy the thrust and handling enhancements you've made. The other important engine-related element is fuel. No fuel means no go. Engine power is influenced by engine parameters such as induction-system design, combustion-chamber configuration, and exhaust. As a result of the Corvette engine's high-performance demands, not just any gasoline will do. The fuel you use should be tailored to match the power demands, so the engine can deliver maximum power throughout the rpm range. The most obvious topic of discussion concerning fuel demands is octane rating.
To learn more about octane basics, we interviewed Art Brown, technical operations manager at Sunoco Racing Fuels.
Simply stated, octane is a measure of a gasoline's antiknock quality or a fuel's resistance to pre-ignition or detonation. Pre-ignition occurs when the Air/Fuel (A/F) mixture is ignited before the spark occurs. Detonation is, by definition, A/F ignition at some location in the combustion chamber away from the plug. The higher the octane number, the higher a fuel's resistance to unintended combustion. Contrary to urban legend, octane isn't a measure of how fast fuel burns.
An engine's octane requirement is directly related to the engine's compression ratio, which is the ratio between the cylinder volume when the piston is at Bottom Dead Center (BDC) and when it's at Top Dead Center (TDC). If the volume at BDC is 1,000 cc, and at TDC it's 100 cc, the ratio would be 10:1. Mechanical items that can influence compression ratio are piston-to-deck clearance, piston dish, dome shape, head-gasket thickness, and combustion-chamber volume.
Compression is important for increasing power in naturally aspirated engines. When A/F is squeezed more tightly together, increased cylinder pressure results after ignition to create additional push on the piston during the power stroke. As the piston rises, the A/F mixture is compressed, which adds heat. If there is a hot spot in the combustion chamber, the mixture could be ignited prematurely before the spark plug fires. So, higher octane is the way pre-ignition or detonation can be controlled during the compression cycle.
An important concept to understand is that combustion is not an explosion. Ideally, it is a flame wave, initiated by the spark, which burns across the combustion chamber. This smooth burning generates the rapid rise in cylinder pressure during the power stroke.
Knock is the negative result when combustion occurs somewhere else in the cylinder, in addition to the plug. Like the spark-plug-initiated flame wave, the second wave expands so a collision between the wave fronts occurs. This collision produces a radical spike in cylinder pressure. Instead of a firm, even push down on the piston, the pressure spike hammers it down. This is strong enough that it can ultimately burn a piston, crack a piston ring or ring land, or a spark-plug electrode. These excessive pressure spikes can damage even engine bearings. When you hear a metallic rattle while driving, that is the sound of detonation and, in most cases, the cure is fuel with the correct octane.
No doubt, you've seen the "RON plus MON divided by 2" formula posted on fuel pumps. As Brown explains, there is the Research Octane Number (RON) and Motor Octane Number (MON). Together, this is the Anti-Knock Index (AKI). RON utilizes a single-cylinder, laboratory test engine running at 600 rpm with an 83-degree F. intake temperature. MON, on the other hand, utilizes a 900-rpm limit and a 300-degree intake temperature. Test data from these engines allows octane to be determined. Because the AKI is an average, you can have very different fuels produce the same AKI. A fuel with a 120 RON octane and a fuel with a MON 102 octane will deliver the same octane number as one with a 113 RON octane and a MON of 109. By blending different fuels, Sunoco can create a cost-effective gasoline with the desired octane.
Knock control was originally accomplished by adding tetraethyl lead. According to Brown, lead was the standard octane booster. He explains, "It does not bind with gasoline, but rather mixes with it." Using lead was a cheap and easy way to boost octane since all you had to do was pour and mix it in. Until the phase-out of lead starting in 1974 (due to toxic lead emissions), it was easy to get enough octane for your Corvette's engine.
Over the past 25 years, compression ratios have climbed back up, thanks to a combination of refined combustion-chamber design characteristics and engine control electronics. Today you can increase compression and power, but remain detonation free with unleaded 92-octane fuel.
Today, Sunoco blends selected fuel stocks in order to achieve a desired octane rating, in addition to meeting EPA-mandated requirements for oxygenates and emissions-reducing formulation. "We formulate fuels with gasoline components as well as oxygenated components and blend them to 100 octane," Brown explains. "You're limited in the amount of octane you can acquire at a reasonable price through the use of hydrocarbon components and oxygenates. This limit is about 104 octane."
There are also mechanical items that can influence an engine's octane requirement. One aspect is combustion-chamber design. Design reflects on how the A/F mixture behaves in the combustion chamber. Early '60s chamber designs often were a closed style. Today's aftermarket heads, depending on the application, often have more open configurations that promote efficient combustion help, contributing to reduced octane sensitivity.
In addition to mechanical considerations, octane requirements in modern Corvettes are influenced by the sophisticated engine control electronics. Today, an LS6 engine with a 10.5:1 compression ratio, and the former ZR-1 with 11:1 compression, will operate on 92-octane unleaded premium. "How that is able to happen is through the engine management computer," Brown says. "It simply takes more timing out of the engine. What we have found is, if you used GT Unleaded (100-octane), that would allow the computer to put more timing back into the engine and you would see an increase in performance, everything else being equal."
To sum up, if you have a new or nearly new Corvette, use the octane grade recommended in your owner's manual. If your older street-driven Corvette has an original high-compression engine, or you've rebuilt it that way, start with Sunoco's 100-octane GT Unleaded premium to make sure there is no detonation. If it's OK there, blend in a 50/50 mix of 94-octane Ultra, and see if knock occurs. When there is none, that's the lowest octane your engine is happy with. Remember, using a higher octane fuel than what your engine needs only costs you more money.
Here's a selection of compression ratios used in Corvette engines over the decades, with the ZL-1 being the ultimate. This was a thinly disguised race engine and required 100-octane fuel, minimum. Note that compression has slowly crept up over time. The reason compression can increase today, yet still use unleaded 92-octane, lies in the refined combustion-chamber configurations and sophisticated engine electronic controls. Also note that the increased compression contributes to increased power, but it is not the sole reason for the power increase.
Year Engine/Cubic
Inches or Liters CR HP '53 235ci 8.0:1 150 '58 Base/283 9.5:1 230 '69 ZL-1/427 12.5:1 435 '70 LT-1/350 11:1 370 '80 L48/350 8.2:1 190 L82/350 9.0:1 230 LG4/305 8.5:1 180 '90 Base/5.7L 9.5:1 245 ZR-1/5.7L 11.0:1 370 '00 LS1/5.7L 10.1:1 345 '03 LS1/ 5.7L 10.1:1 345 LS6/5.7L 10.5:1 405
If you don't know an engine's compression, you need to measure the elements that determine the compression ratio in order to calculate it. There are mathematical formulas to do it manually, but we have discovered an online compression-ratio calculator.
At the Ross Racing Pistons Web site (www.rosspistons.com), there is a c.r. calculator, where you need only to type in the numbers, and, with a click of the mouse, get your answer. Here's an explanation of the factors, and where to find your specifications.
Bore: In inches
Stroke: In inches
Head volume: This is the combustion-chamber volume in cc's. Head manufacturers have these figures listed in their specs. If you're working with a factory head, or one that's been milled, you will have to measure the volume.
Gasket thickness: In thousandths of an inch. Gasket manufacturers will have this specification.
Deck clearance: In inches. Typically, at top dead center, the piston top is located slightly below the block-deck surface. Your machine shop can give you the dimension.
Piston dish or dome volume: In cc's. A dish increases volume, while a dome decreases it. These specifications are available from the piston manufacturer.
Hey rbryce, This is the most interesting article I have read on the subject of Octane ratings. Excellent job man. I have always used premium fuel in my c5, and now I know I am not wasting my dollars, especially in the long run. I hope every one gets to read this. I worked at a Sunoco filling station in Chicago back in the late 50's. They had a pump that you could go from Regular all the way up to their highest Octane, I forget what the numbers were, but all the young guys with hot cars (including me) would always fill up with the highest one, and then go out to Skips Drive In on North Avenue out in Maywood and try to pick a race. I won more than I lost. I had a 56 Bel Air hardtop with a 265ci, dual exaust, barrel carb, stick shift with overdrive, this give me a 411 rear end, and I swore the Sunoco made me faster. Thanks for the article, especially the Sunoco part. Sure brought back memories. Scott
R
RVN
Guest
rbryce, can you provide us with a link to the article please? It sounds like it's from a very informative website with information that could benefit everybody. Also, more modelsHere is an article I read, and I found it to be really good. It seems to cover practically all bases about octane, where it comes from, how it can be modified, what your engine needs and why, and how modern engines can adjust while the older ones cannot. Hope this helps.
The model isn't bad either!
Corvette Fuel Octane - Burning Questions
Thanks!. . .
R
rbryce
Guest
Link to above article
http://www.corvettefever.com/techarticles/corp_0402_corvette_fuel_octane/index.html
http://www.corvettefever.com/techarticles/corp_0402_corvette_fuel_octane/index.html
R
RVN
Guest
Thanks!
Hib Halverson
Technical Writer for Internet & Print Media
This gasoline thing is pretty simple.
With a few exceptions (mainly ZR-1s and ZR1s) any Corvette that "recommends" premium fuel can run "safely" on 87 octane gas or "regular" unleaded fuel.
ZR-1s and ZR1s which say "premium required" either on a placard placed near the fuel filler door on ZR-1s) or in the owner's manual (ZR1s) cannot be run on 87 oct.
Of cars which are recommended to use premium, some were calibrated for 91-oct gas, but more recently, cars which were recommended to use premium were calibrated for 93-oct. The reason for the change is some GM slight-of-hand in tuning for more octane to raise power ratings. In reality, not all Corvette owners can take advantage of that power becuase 93-octane gas is only available in the upper mid-west and the northeast and mid-Atlantic part of the country.
When you use 87 octane gas you:
1) loose performance, due to the EST feature retarding spark to eliminate detonation when running on cheap fuel
2) loose fuel economy because of the retarded spark.
3) gain coolant temperature because of the retarded spark.
Lastly, if you have a car calibrated to run on 93, but you can only get 91 oct in your rear, you will see slight knock retard during WOT operation, even on cool days.
With a few exceptions (mainly ZR-1s and ZR1s) any Corvette that "recommends" premium fuel can run "safely" on 87 octane gas or "regular" unleaded fuel.
ZR-1s and ZR1s which say "premium required" either on a placard placed near the fuel filler door on ZR-1s) or in the owner's manual (ZR1s) cannot be run on 87 oct.
Of cars which are recommended to use premium, some were calibrated for 91-oct gas, but more recently, cars which were recommended to use premium were calibrated for 93-oct. The reason for the change is some GM slight-of-hand in tuning for more octane to raise power ratings. In reality, not all Corvette owners can take advantage of that power becuase 93-octane gas is only available in the upper mid-west and the northeast and mid-Atlantic part of the country.
When you use 87 octane gas you:
1) loose performance, due to the EST feature retarding spark to eliminate detonation when running on cheap fuel
2) loose fuel economy because of the retarded spark.
3) gain coolant temperature because of the retarded spark.
Lastly, if you have a car calibrated to run on 93, but you can only get 91 oct in your rear, you will see slight knock retard during WOT operation, even on cool days.
Hib Halverson
Technical Writer for Internet & Print Media
Actually, it's not called a "spark retarder".
It is called EST or "electronic spark control." It works on a feedback loop.
As soon as the knock sensor detects detonation--and it can detect it even if the knock is inaudible--EST retards spark a couple of degrees. If the detonation ceases, the spark is held at the retarded figure for a short time then is re-advanced to the base spark calibration. If the detonation persists, EST retards another 2 deg and so on and so forth.
This system works very quickly. Once the KS detects knock, before the next time that cylinder fires, the ECM will have retarded the spark.
The statement about "knock insurance" is pointless other than to underline the fact that premium fuel doesn't cost that much more. When EST is working, the minimal amount of knock that occurs is not detrimental.
Yes, the engine will run better on premium unleaded, but as long as EST is working properly, there is no harm in using lower octane fuel as long as you're willing to take the performance and fuel mileage hit.
Even with the engine is using premium, you will experience knock retard on hot days. Thing is, most people can't even tell it's happening unless they are monitering the ECM's serial data with a scan tester and "see" the knock retard or knock counts.
Most Corvettes built after the mid-90s require 94.5-95 octane to keep them out of detonation all the time.
It is called EST or "electronic spark control." It works on a feedback loop.
As soon as the knock sensor detects detonation--and it can detect it even if the knock is inaudible--EST retards spark a couple of degrees. If the detonation ceases, the spark is held at the retarded figure for a short time then is re-advanced to the base spark calibration. If the detonation persists, EST retards another 2 deg and so on and so forth.
This system works very quickly. Once the KS detects knock, before the next time that cylinder fires, the ECM will have retarded the spark.
The statement about "knock insurance" is pointless other than to underline the fact that premium fuel doesn't cost that much more. When EST is working, the minimal amount of knock that occurs is not detrimental.
Yes, the engine will run better on premium unleaded, but as long as EST is working properly, there is no harm in using lower octane fuel as long as you're willing to take the performance and fuel mileage hit.
Even with the engine is using premium, you will experience knock retard on hot days. Thing is, most people can't even tell it's happening unless they are monitering the ECM's serial data with a scan tester and "see" the knock retard or knock counts.
Most Corvettes built after the mid-90s require 94.5-95 octane to keep them out of detonation all the time.
C
Chemdawg99
Guest
IMHO, the bottom line is to just stop being cheap and run 91 or better in your Vette.
U.P. John
Well-known member
Quote:
Originally Posted by gmjunkie
I run regular 87 octane Chevron or Texaco in all my Vehicles that have a Brain!!!
Originally Posted by gmjunkie
I run regular 87 octane Chevron or Texaco in all my Vehicles that have a Brain!!!
I suggest serious thought before you take any advice from this man!
GM Junkie is not a man. GM Junkie is a good looking old broad. Not much ballast, but she covers it up well. She always carries a bottle of "squeezins" so you don't focus on her lack of sweater meat. Trust me on this.
Too bad they cancelled Extreme Makeovers. She could use one!
And if anyone knows about gas, it's Gm Junkie. She's AOK in my book!!
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Please make sure that if you post articles in the forums here from magazines and other media sources - that you include the authors name and the publication that the article came from.
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Well for what's worth, the dealership that looks after my 2003, has a Chevy Master Machanic there who only works on Corvettes for them, but he was telling me that a lot of gasoline companies sold off their stations, which allows the owner to buy any gas, the cheaper the better. And that a lot of fuel out there that is pure junk. He said to use Shell, Chevron, ExxonMobil and alway use at LEAST 91 Octane. Many fuels he said have way too much Sulfur in them. And that the Sulfur eats away at the small metal parts in the fuel pumps and injectors. There's a website that lists the 'Top Tier' fuels available. As for me, I paid 50K for my car, I sure as hell can afford the price of 93 octane. The car runs better, I believe like many here, that I get better milage, (I get 30.2 MPG on the turnpike) and I sure I can appreciate the punch I get out of hitting the gas pedal and having something special happen. I'm older, don't have money to waste, but if I got to the point where the cost of good fuel was an issue, I'd sell the car.
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Chemdawg99
Guest
Well for what's worth, the dealership that looks after my 2003, has a Chevy Master Machanic there who only works on Corvettes for them, but he was telling me that a lot of gasoline companies sold off their stations, which allows the owner to bey any gas, the cheaper the better. And that a lot of fuel out there that is pure junk. He said to use Shell, Chevron, ExxonMobil and alway use at LEAST 91 Octane. Many fuels he said have way too much Sulfur in them. And that the Sulfur eats away at the small metal parts in the fuel pumps and injectors. There's a website that lists the 'Top Tier' fuels available. As for me, I paid 50K for my car, I sure as hell can afford the price of 93 octane. The car runs better, I believe like many here, that I get better milage, (I get 30.2 MPG on the turnpike) and I sure I can appreciate the punch I get out of hitting the gas pedal and having something special happen. I'm older, don't have money to waste, but if I got to the point where the cost of good fuel was an issue, I'd sell the car.
My sentiments exactly
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I should say that I don't waste or throw money away. Here in Pennsylvania and many of the surrounding states sell only 87 octane, 89 or 93. And 91 octane is a little difficult to find, but there is so little difference, I just fuel up with Exxon 93 ! Car runs great .
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I think 93 Octane is only available in certain regions. I've only ever seen it at the pump when I took trips back to Bowling Green, and it seemed to be primarily east of the Mississippi River. I just got back from a trip to Washington State, and going through Wyoming, Montana, Idaho and Washington State, the highest available octane rating was 91.
The trick is to buy the highest available octane rating in your area.
There used to be a gas station here in the Denver area that sold racing grade fuel, with a 104 Octane rating available- rather pricey, too. I never knew about it until I met someone at a car show who mentioned it, and said it worth the price for the way his Corvette performed. Unfortunately, I don't think that station is there anymore.
Vette_Dreaming
Well-known member
FYI, Patrick there is station in Wheat Ridget that has racing grade fuel. That might be quite a drive for you to fill up, though.
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- 2003 50th Annversary Red coupe, beautiful !
It's interesting, Gasoline. The price of a barrel of oil just dropped below $100.00, yet around here the price of Gasoline went up $0.25 just last night. Another strange thing I've noticed around here in SE Pennsylvania, is the brand name gas stations are disappearing ! The Texaco station close last year, it was suppose to reopen as a Shell, but that fell through so it's closed now. The local mobile stations have changed to 'Lukoil' stations. The BP station up the road has closed last night and is reopened now this afternoon as a no brand station called just 'Cheap Gas' station in a big blue and white sign. Like wise, the quality of the fuel sold is up for debate, and the octane available is changing as fast as the station signage. The only constant gasoline here is Sunoco, as they have a huge refinery in South Philadelphia. I don't know about where you live, but around here it's getting strange as far as gasoline is concerned.:ugh
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