Jalopnik used to be full of car enthusiasts- this doesnt seem to be the case anymore. This guy has a decidedly anti big oil slant. Thats fine. I think big oil does need to be replaced by something renewable and cleaner, but I still dont really enjoy reading his series. Its a bit smug and virtuous for me. There are still a few good writers at Jalopnik. Jason Torchinsky, despite his extreme desire to see tesla/elon musk burn writes a lot of great stuff about the quirks of cars that you may otherwise overlook. David Tracy seems to be a glutton for the punishment that only rusty jeeps can supply. Mercedes Streeter has had a few articles I liked. By and large it seems that most of the regular staff writers hate cars, or at least cars that arent non tesla electrics/hybrids.
Now about leaded fuel. Back before say, 1970ish a lot of gas had an octane rating of between 40-70[1]. Refining oil was still an emerging technology. That being the case it seems like one of the by products of Natural Gas Liquids(called Natural Gasoline) was being used as pump gas. Lets pretend that you built a time machine and took your brand new 2022 camry with you to have a laugh that a consumer commuter car would be a super car back in the 1940s. If you managed to find fuel that was unleaded you would likely do irreversible engine damage on the first tank. If you filled with leaded, your catalytic converter would foul and then you would need to remove it to run leaded fuel. Lead was an additive because it prevents detonation in sub-optimal gas. After lead was outlawed they started boosting octane to do the same function. Fuel sucked, and it wasnt until lead was outlawed that refining higher quality fuels on a large scale became possible. I see the clean air act as a great example of successful regulation.
> Fuel sucked, and it wasnt until lead was outlawed that refining higher quality fuels on a large scale became possible
You seem to be arguing your point backwards to me. Lead was only outlawed when refining advanced to a level to permit economically viable high octane fuel without it.
The author would seem to argue they stopped looking for viable methods to avoid the problem when lead arrived, because its costs were pure externalities. Most of the problems with ICE are externalities. The NO burden in diesel for instance, or the PM10 thing, is not really any different to the lead problem. If you own stocks in Oil you don't care that its causing cancer to anyone who lives close to a road, or dumbing down kids, or causing global warning. Why would you?
I can't really disagree with your first point, But I suspect the future of jalopnik is to convince Americans (and it is mainly about Americans) to spend disposable income on either EV, or EV conversion of classic cars. If it sticks to its cylinders, it will become sidelined by the market shift: They'd rather try to define the shift and be part of the shift.
I love steam engines btw. I would totally love to have a stanly steamer, or the air pressure modifed 4-cylinder cars which started off silently because one cylinder was air forced and drove it until the other 3 started up some distance from your fine castle... But I don't see anyone selling me "Jalopnik for steam" which maybe is realistic, but sucks if you like steam.
If you love ICE, you won't like the future. It's going to be niche. Maybe Jalopnik is 25+_years ahead of the game here, which is (I freely admit) stupid.
I’m an ICE fan but I think the opposite. Let every soccer mom and commuter use electric cars, even self driving cars if we have the technology. Electric is perfect for them.
For those of us who like combustion engines, we’ll be happy that the remaining supply of fossil fuels is kept around for enthusiasts and collectors, and not wasted. With expiring patents and less competition from the big automakers we might even get to see increasingly interesting technologies. Heck maybe in 2040 we’ll be able to 3D print replacement engine parts at home. The future could unlock all sorts of possibilities.
Of for fans? Sure. There are clubs for people who like penny farthings and special licences for cars without seatbelts. Maybe ICE cars will be on the shriners parade being driven by men in silly hats (ww2 vehicle owners do LARP on memorial day here, some people do the same on horses)
> You seem to be arguing your point backwards to me. Lead was only outlawed when refining advanced to a level to permit economically viable high octane fuel without it.
Ethyl alcohol was an option, but:
> Kettering himself had designed the self-starter a decade before, wrote James Lincoln Kitman for The Nation in 2000, and the knocking was a problem he couldn’t wait to solve. It made cars less efficient and more intimidating to consumers because of the loud noise. But there were other effective anti-knock agents. Kitman writes that Midgley himself said he tried any substance he could find in the search for an antiknock, “from melted butter and camphor to ethyl acetate and aluminum chloride.” The most compelling option was actually ethanol.
> But from the perspective of GM, Kitman wrote, ethanol wasn’t an option. It couldn’t be patented and GM couldn’t control its production. And oil companies like Du Pont "hated it," he wrote, perceiving it to be a threat to their control of the internal combustion engine.
> TEL filled the same technical function as ethanol, he wrote: it reduced knock by raising the fuel's combustability, what would come to be known as "octane." Unlike ethanol, though, it couldn't be potentially used as a replacement for gasoline, as it had been in some early cars. The drawback: it was a known poison, described in 1922 by a Du Pont executive as "a colorless liquid of sweetish odor, very poisonous if absorbed through the skin, resulting in lead poisoning almost immediately." That statement is important, Kitman wrote: later, major players would deny they knew TEL to be so poisonous.
How does high octane fuel for aviation figure into the history of gasoline? If I remember correctly 100 octane gasoline was used for aviation during World War II before the rise of jet engines shifted aviation to using jet fuel.
This is the green-dyed 130 octane which is basically blended from stocks somewhat similar but cleaner than high-octane unleaded "conventional" automotive gasoline.
The base stocks without lead could be about like the blue 100LL and lead is added to bring it up to 130 on a "supercharge" rating not exactly like the Research and Motor methods are conducted on the test engines.
Relatedly, the connection between leaded gasoline and the rise and subsequent fall in crime is woefully under-reported. It's been studied in the public health literature for a long time, and has only gotten a bit of reporting here and there, starting with Drum:
Some things are huge conspiracies. it's no doubt to me that the fossil fuels industry is full of people who are and have conspired to make the world a vastly worse place because it is profitable to do so.
Interesting topic. I recently got my first own car (have been driving for almost two decades, though) and started to learn about how it works in some detail. Regarding gasoline - I just found out that my car (as most cars since the 2000s) works just fine with E10 (up to 10% bio ethanol). In Germany, though, this is still a heated subject due to intentional misinformation around 2010 by oil lobby and associates (ADAC first and foremost).
Here's what I learned about E10:
It's likely about as energetic as regular fuel (the chemical energy reasoning falls short due to side effects).
Its Octane Number is higher than regular fuel due to ethanol's Octane Number.
It burns cleaner (less coking) and also has a cleaning effect - again due to the higher ethanol content.
It's hydrophile qualities are actually an advantage as that means it binds water which is entering the system.
Some gas stations sell regular as E10 (and then cheaper) because it isn't economic or possible for them to have yet another type of fuel in reserve.
The reason why oil industry hates E10 is because it is more expensive for them while by law (in EU) they are forced to sell it cheaper.
---
There's only one catch which I still didn't wrap my head around.
My Mazda brings 160k kms to the table and features a "maintenance free" in-tank fuel filter which is somewhat difficult to replace. Now I'm a bit worried that using E10 will release built up residue attached to the tank and clog the fuel filter. And I don't know how fast this would take place.
It's likely about as energetic as regular fuel...
Its Octane Number is higher than regular fuel
I am not a petroleum chemist/engineer/whatever, but I'm pretty sure those two things cannot be true at the same time. Higher octane fuel contains less energy, which contributes to less engine knock/pre-detonation.
"The other rarely-discussed reality with high-octane fuels associated with 'high performance' is that as octane increases, the specific gravity and energy content of the fuel per unit of weight are reduced. The net result is that to make a given amount of power, more high-octane fuel must be burned in the engine."
>It's likely about as energetic as regular fuel... Its Octane Number is higher than regular fuel
>I'm pretty sure those two things cannot be true at the same time.
I agree, I'd give better odds it's less likely myself. That's the type of petroleum chemist I am.
>as octane increases, the specific gravity and energy content of the fuel per unit of weight are reduced. The net result is that to make a given amount of power, more high-octane fuel must be burned in the engine.
But this isn't really true either.
The wiki snippet I've quoted here is just plain uncertain on its own, even though this can be an actual trend it is only true when the octane-boosting blend component(s) have a lighter specific gravity than the base stock hydrocarbons. Not nearly as commonly seen to support such a generalization. This happened more often with MTBE than ethanol.
As far as the amount of fuel that must be burned by comparison, ethanol's influence on the specific gravity of the gasoline does not have as big an effect as the oxygen content of the alcohol itself.
Ethanol is almost 35 percent oxygen by weight, the remainder of the molecule is carbon & hydrogen.
Plain hydrocarbons whether aromatic structures or not are just carbon & hydrogen arrangements with no other elements included.
The ethanol can be considered to have a big percentage of its carbon already "oxidized" or chemically combined with oxygen naturally in advance of its energy-releasing combustion, which then releases the remaining energy when it combusts in combination with fresh oxygen from the engine air intake.
So with oxygenate additives lots of space in your tank is occupied by the dead weight of its oxygen content, which doesn't contribute to energy release like the carbon content does. Unlike with conventional plain hydrocarbon fuels which pack more carbon per gallon.
This is where specific gravity can be easier to understand.
Even though it is a unitless number and for our purposes exists only in the mathematical realm 0.6 < SG < 0.9
Hydrocarbons pack the most punch per gallon, but some hydrocarbons are heavier than others depending on structure. To a very strong extent the more carbon molecules in the structure of a particular refined hydrocarbon, it will weigh more per gallon and have a resulting higher specific gravity.
And energy content is commonly measured in BTU per weight regardless of specific gravity.
So when it is plain hydrocarbons the higher the specific gravity, the more energy you can carry in the same tank, and with miles per gallon trending up naturally.
Which is one of the advantages of diesel since it doesn't contain any of the light flammable vapors that are essential to gasoline engines. So diesel is just plain heavier per gallon and that's a big reason you get more miles per gallon with diesel.
Now chemically aromatic ring structures have a higher carbon/hydrogen ratio compared to paraffinic chains, and physically turn out to be a big notch higher in specific gravity across the board compared to their paraffinic counterparts having the same number of carbon atoms per molecule.
Benzene itself is the simplest characteristic hexagonal aromatic ring structure, known as benzol in the first half of the 20th century, low freeze-point mixtures were sold as premium fuel for early gasoline motorcars. Since it basically runs 100 (R+M)/2 on its own people paid more.
Benzene has been widely reduced by regulations but along with a handful of other light aromatics they have a high octane contribution and a high specific gravity contribution at the same time.
Considering the fundamental basis of conventional hydrocarbon gasoline this is about the opposite of what this part of Wikipedia says.
Going further when you have for example 87 octane conventional unleaded gasoline this is a high aromatic fuel with high specific gravity.
If you were to boost the antiknock rating to 90 or more by adding alcohol or MTBE e...
But when a gasoline engine doesn't knock, you can get more power out of it by consuming more fuel faster and more smoothly though.
No, you get more power out of it by advancing the timing and increasing the compression, both of which will cause an engine to knock with lower octane fuels. Perhaps that's what you are saying, but it didn't seem clear to me.
Thanks for the extensive write-up. Many of these types of questions can thankfully be answered on a dyno, but a little knowledge of what's going on never hurts.
Higher compression yields better fuel efficiency and power. But the concomitant higher compression produces higher temperatures pushing the fuel air mixture past the flash point.
Aircraft engines during takeoff commonly increase mixture to cool things down at the cost of unconsumed fuel.
Water-methanol injection was also used in late high power piston engines during takeoff and even in early turbine engines such as the Dart in the Viscount.
In the mid '70s I bought a Renault 5. After leaving the dealer I read the owner manual and discovered that it required premium gasoline. A year or two later, premium was displaced by unleaded and I had a knock problem. Being a pilot I found that a couple gallons of 100 octane aviation fuel mixed with a tank of regular fixed the knock problem. Long trips were managed from airport to airport and a carried an Explosafe™ fuel container for when an airport was not in reach.
Aviation octane went up to 130,but was phased out when the airlines dropped their piston fleets.
130 octane was a major factor in the Allies winning WWII.
19 comments
[ 2.6 ms ] story [ 41.8 ms ] threadNow about leaded fuel. Back before say, 1970ish a lot of gas had an octane rating of between 40-70[1]. Refining oil was still an emerging technology. That being the case it seems like one of the by products of Natural Gas Liquids(called Natural Gasoline) was being used as pump gas. Lets pretend that you built a time machine and took your brand new 2022 camry with you to have a laugh that a consumer commuter car would be a super car back in the 1940s. If you managed to find fuel that was unleaded you would likely do irreversible engine damage on the first tank. If you filled with leaded, your catalytic converter would foul and then you would need to remove it to run leaded fuel. Lead was an additive because it prevents detonation in sub-optimal gas. After lead was outlawed they started boosting octane to do the same function. Fuel sucked, and it wasnt until lead was outlawed that refining higher quality fuels on a large scale became possible. I see the clean air act as a great example of successful regulation.
[1]https://www.energy.gov/eere/vehicles/fact-940-august-29-2016...
You seem to be arguing your point backwards to me. Lead was only outlawed when refining advanced to a level to permit economically viable high octane fuel without it.
The author would seem to argue they stopped looking for viable methods to avoid the problem when lead arrived, because its costs were pure externalities. Most of the problems with ICE are externalities. The NO burden in diesel for instance, or the PM10 thing, is not really any different to the lead problem. If you own stocks in Oil you don't care that its causing cancer to anyone who lives close to a road, or dumbing down kids, or causing global warning. Why would you?
I can't really disagree with your first point, But I suspect the future of jalopnik is to convince Americans (and it is mainly about Americans) to spend disposable income on either EV, or EV conversion of classic cars. If it sticks to its cylinders, it will become sidelined by the market shift: They'd rather try to define the shift and be part of the shift.
I love steam engines btw. I would totally love to have a stanly steamer, or the air pressure modifed 4-cylinder cars which started off silently because one cylinder was air forced and drove it until the other 3 started up some distance from your fine castle... But I don't see anyone selling me "Jalopnik for steam" which maybe is realistic, but sucks if you like steam.
If you love ICE, you won't like the future. It's going to be niche. Maybe Jalopnik is 25+_years ahead of the game here, which is (I freely admit) stupid.
I’m an ICE fan but I think the opposite. Let every soccer mom and commuter use electric cars, even self driving cars if we have the technology. Electric is perfect for them.
For those of us who like combustion engines, we’ll be happy that the remaining supply of fossil fuels is kept around for enthusiasts and collectors, and not wasted. With expiring patents and less competition from the big automakers we might even get to see increasingly interesting technologies. Heck maybe in 2040 we’ll be able to 3D print replacement engine parts at home. The future could unlock all sorts of possibilities.
Ethyl alcohol was an option, but:
> Kettering himself had designed the self-starter a decade before, wrote James Lincoln Kitman for The Nation in 2000, and the knocking was a problem he couldn’t wait to solve. It made cars less efficient and more intimidating to consumers because of the loud noise. But there were other effective anti-knock agents. Kitman writes that Midgley himself said he tried any substance he could find in the search for an antiknock, “from melted butter and camphor to ethyl acetate and aluminum chloride.” The most compelling option was actually ethanol.
> But from the perspective of GM, Kitman wrote, ethanol wasn’t an option. It couldn’t be patented and GM couldn’t control its production. And oil companies like Du Pont "hated it," he wrote, perceiving it to be a threat to their control of the internal combustion engine.
> TEL filled the same technical function as ethanol, he wrote: it reduced knock by raising the fuel's combustability, what would come to be known as "octane." Unlike ethanol, though, it couldn't be potentially used as a replacement for gasoline, as it had been in some early cars. The drawback: it was a known poison, described in 1922 by a Du Pont executive as "a colorless liquid of sweetish odor, very poisonous if absorbed through the skin, resulting in lead poisoning almost immediately." That statement is important, Kitman wrote: later, major players would deny they knew TEL to be so poisonous.
* https://www.smithsonianmag.com/smart-news/leaded-gas-poison-...
The base stocks without lead could be about like the blue 100LL and lead is added to bring it up to 130 on a "supercharge" rating not exactly like the Research and Motor methods are conducted on the test engines.
https://www.motherjones.com/environment/2016/02/lead-exposur...
https://www.motherjones.com/kevin-drum/2018/02/an-updated-le...
The subtitle is "Part 8: People might have put less trust in leaded gasoline if they'd known how much of a shitshow the lab was that invented it"
And yet the word "trust" does not show up anywhere in the article.
Here's what I learned about E10:
It's likely about as energetic as regular fuel (the chemical energy reasoning falls short due to side effects).
Its Octane Number is higher than regular fuel due to ethanol's Octane Number.
It burns cleaner (less coking) and also has a cleaning effect - again due to the higher ethanol content.
It's hydrophile qualities are actually an advantage as that means it binds water which is entering the system.
Some gas stations sell regular as E10 (and then cheaper) because it isn't economic or possible for them to have yet another type of fuel in reserve.
The reason why oil industry hates E10 is because it is more expensive for them while by law (in EU) they are forced to sell it cheaper.
---
There's only one catch which I still didn't wrap my head around.
My Mazda brings 160k kms to the table and features a "maintenance free" in-tank fuel filter which is somewhat difficult to replace. Now I'm a bit worried that using E10 will release built up residue attached to the tank and clog the fuel filter. And I don't know how fast this would take place.
I am not a petroleum chemist/engineer/whatever, but I'm pretty sure those two things cannot be true at the same time. Higher octane fuel contains less energy, which contributes to less engine knock/pre-detonation.
https://en.wikipedia.org/wiki/Octane_rating#Effects
"The other rarely-discussed reality with high-octane fuels associated with 'high performance' is that as octane increases, the specific gravity and energy content of the fuel per unit of weight are reduced. The net result is that to make a given amount of power, more high-octane fuel must be burned in the engine."
>I'm pretty sure those two things cannot be true at the same time.
I agree, I'd give better odds it's less likely myself. That's the type of petroleum chemist I am.
>as octane increases, the specific gravity and energy content of the fuel per unit of weight are reduced. The net result is that to make a given amount of power, more high-octane fuel must be burned in the engine.
But this isn't really true either.
The wiki snippet I've quoted here is just plain uncertain on its own, even though this can be an actual trend it is only true when the octane-boosting blend component(s) have a lighter specific gravity than the base stock hydrocarbons. Not nearly as commonly seen to support such a generalization. This happened more often with MTBE than ethanol.
As far as the amount of fuel that must be burned by comparison, ethanol's influence on the specific gravity of the gasoline does not have as big an effect as the oxygen content of the alcohol itself.
Ethanol is almost 35 percent oxygen by weight, the remainder of the molecule is carbon & hydrogen.
Plain hydrocarbons whether aromatic structures or not are just carbon & hydrogen arrangements with no other elements included.
The ethanol can be considered to have a big percentage of its carbon already "oxidized" or chemically combined with oxygen naturally in advance of its energy-releasing combustion, which then releases the remaining energy when it combusts in combination with fresh oxygen from the engine air intake.
So with oxygenate additives lots of space in your tank is occupied by the dead weight of its oxygen content, which doesn't contribute to energy release like the carbon content does. Unlike with conventional plain hydrocarbon fuels which pack more carbon per gallon.
This is where specific gravity can be easier to understand.
Even though it is a unitless number and for our purposes exists only in the mathematical realm 0.6 < SG < 0.9
Hydrocarbons pack the most punch per gallon, but some hydrocarbons are heavier than others depending on structure. To a very strong extent the more carbon molecules in the structure of a particular refined hydrocarbon, it will weigh more per gallon and have a resulting higher specific gravity.
And energy content is commonly measured in BTU per weight regardless of specific gravity.
So when it is plain hydrocarbons the higher the specific gravity, the more energy you can carry in the same tank, and with miles per gallon trending up naturally.
Which is one of the advantages of diesel since it doesn't contain any of the light flammable vapors that are essential to gasoline engines. So diesel is just plain heavier per gallon and that's a big reason you get more miles per gallon with diesel.
Now chemically aromatic ring structures have a higher carbon/hydrogen ratio compared to paraffinic chains, and physically turn out to be a big notch higher in specific gravity across the board compared to their paraffinic counterparts having the same number of carbon atoms per molecule.
Benzene itself is the simplest characteristic hexagonal aromatic ring structure, known as benzol in the first half of the 20th century, low freeze-point mixtures were sold as premium fuel for early gasoline motorcars. Since it basically runs 100 (R+M)/2 on its own people paid more.
Benzene has been widely reduced by regulations but along with a handful of other light aromatics they have a high octane contribution and a high specific gravity contribution at the same time.
Considering the fundamental basis of conventional hydrocarbon gasoline this is about the opposite of what this part of Wikipedia says.
Going further when you have for example 87 octane conventional unleaded gasoline this is a high aromatic fuel with high specific gravity.
If you were to boost the antiknock rating to 90 or more by adding alcohol or MTBE e...
No, you get more power out of it by advancing the timing and increasing the compression, both of which will cause an engine to knock with lower octane fuels. Perhaps that's what you are saying, but it didn't seem clear to me.
Thanks for the extensive write-up. Many of these types of questions can thankfully be answered on a dyno, but a little knowledge of what's going on never hurts.
Aircraft engines during takeoff commonly increase mixture to cool things down at the cost of unconsumed fuel.
Water-methanol injection was also used in late high power piston engines during takeoff and even in early turbine engines such as the Dart in the Viscount.
In the mid '70s I bought a Renault 5. After leaving the dealer I read the owner manual and discovered that it required premium gasoline. A year or two later, premium was displaced by unleaded and I had a knock problem. Being a pilot I found that a couple gallons of 100 octane aviation fuel mixed with a tank of regular fixed the knock problem. Long trips were managed from airport to airport and a carried an Explosafe™ fuel container for when an airport was not in reach.
Aviation octane went up to 130,but was phased out when the airlines dropped their piston fleets.
130 octane was a major factor in the Allies winning WWII.