Why is mid grade more expensive

Messages
251
Location
Bowling Green, OH
I've worked at both the refining and retail side of automotive fuel. Currently in my neck of the woods: Low Grade w/Ethanol starts out as unbranded 84 octane and is blended at the terminal 9 parts gas / 1 part ethanol to create 87 octane High Grade w/Ethanol starts out as unbranded 91 octane and is blended at the terminal 9 parts gas / 1 part ethanol to create 93 octane Mid Grade is usually blended at the Dispenser 66% 87 octane / 34% 93 octane. (I've programed dispensers). The few stations that still have a mid grade underground tank will blend at the terminals. (Check the gas station's tank farm for blue caps). Any E0 fuels are blended at the terminals with 84 E0 and 91 E0. A few stations will blend E-85 with low grade E10 for 88 E15.
 
Messages
2,495
Location
IL
Originally Posted by Mad_Hatter
Originally Posted by pschnahc
Seems like a nice way to extort the octane "on the fencers" for the convenience factor. If you want the fairest price for true mid-grade fuel, you gotta pump the low and high octane yourself. I used to do this. Always pump premium first, then the regular...don't want to leave a liter of paid high octane fuel in the pumps lines wink
That's not how it works. You pay for $20 in premium, you get $20 out of the nozzle. A station would get in trouble with weights and measures and your AG for not dispensing the dollar equivalent. In other words, any fuel in the line is already factored into the metering.
So I'm the only one that shuts off the latch and keeps pumping out that last 1/8th cup of gas in the line?
 
Messages
4,165
Location
WA
Originally Posted by Vern_in_IL
So I'm the only one that shuts off the latch and keeps pumping out that last 1/8th cup of gas in the line?
Nope, I do it too. I want every last drop of that sweet dinosaur tears!...‚
 
Messages
271
Location
Northeast Georgia
A LOT of misinformation here. When E10 89 octane (mid-grade) is blended during loading, it is broken down as follows: E10 89 octane is broken down as follows... 31% - 90 octane CBOB 59% - 84 octane CBOB 10% - 111 octane ethanol Equals 100% E10 89 octane mid-grade At the retail pump, it's blended as 66% Reg/34% Prem
 
Messages
5,242
Location
San Francisco Bay Area
Originally Posted by GoldDot40
A LOT of misinformation here. When E10 89 octane (mid-grade) is blended during loading, it is broken down as follows: E10 89 octane is broken down as follows... 31% - 90 octane CBOB 59% - 84 octane CBOB 10% - 111 octane ethanol Equals 100% E10 89 octane mid-grade At the retail pump, it's blended as 66% Reg/34% Prem
Depends on the setup. Once I was pumping gas while a driver was delivering fuel. I asked him whether the mid-grade at this station was blended, and he showed me the seam of the divider in one of the trailer tanks along with the two connectors on either side of the tank. He said it went straight into a separate underground tank. But there are programmable blending pumps. I've seen some with 5 or six different selections. This one I saw at one station obviously used 100 octane street legal race gas to make 100/98/96/94 octane.
 
Messages
271
Location
Northeast Georgia
Originally Posted by y_p_w
Originally Posted by GoldDot40
A LOT of misinformation here. When E10 89 octane (mid-grade) is blended during loading, it is broken down as follows: E10 89 octane is broken down as follows... 31% - 90 octane CBOB 59% - 84 octane CBOB 10% - 111 octane ethanol Equals 100% E10 89 octane mid-grade At the retail pump, it's blended as 66% Reg/34% Prem
Depends on the setup. Once I was pumping gas while a driver was delivering fuel. I asked him whether the mid-grade at this station was blended, and he showed me the seam of the divider in one of the trailer tanks along with the two connectors on either side of the tank. He said it went straight into a separate underground tank.
Not sure what you mean by this. All of our tankers are divided. I can haul 87, 89, 93, and diesel all at the same time. If I load 89 at the terminal, it is broken down as previous stated.
 
Messages
5,242
Location
San Francisco Bay Area
Originally Posted by GoldDot40
Not sure what you mean by this. All of our tankers are divided. I can haul 87, 89, 93, and diesel all at the same time. If I load 89 at the terminal, it is broken down as previous stated.
Wasn't sure what you were mentioning - but I get you're talking about how it gets there at the terminal into your tanks. However, a lot of gas stations around here only use programmed blending pumps. 50-50 87/91 would do the trick to make 89.
 
Messages
271
Location
Northeast Georgia
Originally Posted by y_p_w
However, a lot of gas stations around here only use programmed blending pumps. 50-50 87/91 would do the trick to make 89.
89 octane blended at the pump is not a 50/50 ratio of reg/prem. The ratio is 66% 87 octane and 34% prem 93 octane here. To blend 89 using 91 octane at the pump still wouldn't be 50%.
 
Messages
5,242
Location
San Francisco Bay Area
Originally Posted by GoldDot40
Originally Posted by y_p_w
However, a lot of gas stations around here only use programmed blending pumps. 50-50 87/91 would do the trick to make 89.
89 octane blended at the pump is not a 50/50 ratio of reg/prem. The ratio is 66% 87 octane and 34% prem 93 octane here. To blend 89 using 91 octane at the pump still wouldn't be 50%.
91 is the standard for premium here in California. We can't find anything higher than that unless it's blended with 100 octane unleaded race gas. Even in neighboring states, premium is typically 92 AKI. I just heard that it's pretty linear math via blending, although I suppose it might not necessarily be an exact 50-50.
 

Deo

Messages
14
Location
Atlanta, GA USA
I like midgrade simply for the higher % of cleaning additives in the one-third that is premium. It might not make great financial sense, but I sleep better at night knowing that every tank is "enhanced" (so to speak) as opposed to an occasional bottle of Techron or whatever.
 
Messages
2,600
Location
San Rafael, CA
Originally Posted by Deo
I like midgrade simply for the higher % of cleaning additives in the one-third that is premium. It might not make great financial sense, but I sleep better at night knowing that every tank is "enhanced" (so to speak) as opposed to an occasional bottle of Techron or whatever.
But it's cheaper to buy the cheaper gas and put a bottle of Techron in every oil change smile seriously, if midgrade helps you sleep it's worth it.
 
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Messages
1,077
Location
Wisconsin
Originally Posted by GoldDot40
Originally Posted by y_p_w
However, a lot of gas stations around here only use programmed blending pumps. 50-50 87/91 would do the trick to make 89.
89 octane blended at the pump is not a 50/50 ratio of reg/prem. The ratio is 66% 87 octane and 34% prem 93 octane here. To blend 89 using 91 octane at the pump still wouldn't be 50%.
We don't have much 92/93 octane, On the rare occasion you find it it's always e10
 
Messages
5,242
Location
San Francisco Bay Area
Originally Posted by dogememe
Originally Posted by Deo
I like midgrade simply for the higher % of cleaning additives in the one-third that is premium. It might not make great financial sense, but I sleep better at night knowing that every tank is "enhanced" (so to speak) as opposed to an occasional bottle of Techron or whatever.
But it's cheaper to buy the cheaper gas and put a bottle of Techron in every oil change smile seriously, if midgrade helps you sleep it's worth it.
Well - Costco doesn't have midgrade. However, I remember being in the middle of nowhere where I found a gas station that only had regular and midgrade.
 
Messages
2,819
Location
Florida
I run regular unleaded in all my vehicles with no problems. If you feel the need to add an additive you can, but, its probably not necessary.
 
Messages
48
Location
Birmingham, Alabama
What is crazy to me is that mid grade (89) is roughly a 2 to 1 mix of regular (87) and premium (93). In Alabama, nearly all of the gas stations either split the cost of mid grade in the middle of regular and premium and many gas stations sell mid grade at a significant markup. By the formula breakdown and 2 to 1 mix, you would think mid grade would be closer to the regular in price. This is why me and my wife run strictly top tier regular in my Tacoma 4 banger and her Subaru Forester. Only my Subaru STi that's been tuned with a few bolt on parts gets premium.
 
Messages
48
Location
Birmingham, Alabama
And one other thing. This was basically a statement from one of my Thermodynamics professors at U of Alabama a couple of semesters ago. We were told that the manufacturer/ brand of gas has more to do with the amount of detergents in the gas than the octane. Think Chevron with Techron and Shell and Nitrogen. The octane rating is the fuels ability to resist detonation or knock. The higher the octane, the more resistant to detonation or knock on an engine. This is why generally your sports cars and turbo charged engines require premium fuel and not regular. It's all for knock resistance due to the increased heat and pressures in the combustion chamber. hornets In Alabama we have mostly Shell gas stations with several Marathons, some Exxons and Chevrons (a lot of Chevrons are rebranding to Shells lately) a few BP's and a few Sunoco's. Of course there are discount distributors as well such as Murphy Express and Sams Club bit they are not top tier. My preference has been for Shell ( I can couple their rewards card with my GasBuddy card for 10 cents or more off a gallon) or for Sunoco.
 
Messages
13,343
Location
1/2 hr N.E. of Detroit
Originally Posted by kstanf150
.25 across the board
Instead of gas stations running 87 - 89 - 93, why hasn't a major brand tried running 87 - 90 - 93? I'd bet it would steal a ton of business from competitors and show the world it knows basic math that says "90" is the correct mid-grade number between 87 and 93.
 
Messages
2,663
Location
Chicagoland
Originally Posted by Triple_Se7en
Originally Posted by kstanf150
.25 across the board
Instead of gas stations running 87 - 89 - 93, why hasn't a major brand tried running 87 - 90 - 93? I'd bet it would steal a ton of business from competitors and show the world it knows basic math that says "90" is the correct mid-grade number between 87 and 93.
It is midway between 87 and 91 though, and most manufacturers tune for 91 or 92 AKI when they're recommending premium. Having 87, 90, and 91 in an area like that doesn't make much sense.
 
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