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Post by silverdragon on Dec 30, 2017 9:19:49 GMT
Just for consideration. In Winter, sudden road closures, whilst you are on them, may be of concern, especially f you are stuck for several hours. Keep that in mind when thinking "I have enough fuel for today".... Do you really?. How many hours will half-a-tank of fuel keep you warm for if stranded in the snow. Hmmm... now there is a thing... is this worth putting as a myth to be tested to see how much fuel is used per hour keeping a stranded car warm enough to survive in?.. how would you propose that idea to the MB's?.. in my truck, about an hour before the engine cools off too much to keep the cab warm. but at the road closure mentioned, it took barely a quarter tank to keep the cab warm all night. because yes, since they were saying vehicles with four wheel drive or chains were allowed to go through, we didn't make an immediate run for a hotel, and so couldn't get a room. My car is not supposed to be all that insulated, so in a real cold snap, will cool down within quarter of an hour, The heavy goods night cabs, they are more insulated, especially those with night heaters, the night heater may only need to cycle once every hour as you say to top up the heat, its warmer than say a Caravan, but noisier than trying to sleep though an earthquake if you get parked next to one that rattles badly. The question I am proposing here, if anyone knows, on a full tank of fuel, in a minus 10 to -20 Celsius stranded in a snow bank situation, on say three quarters of an average tank, how long before the fuel would run out?. On average, my sub 2ltr engine with a 11 gallon {uk not short ton USA gallon, this is 8 pints to a gallon] tank of fuel, sitting idling at perhaps just short of 1,000 rpm maybe 1100 rpm with fan and a/c [reduces moisture so windows dont steam up] running, if I am lucky enough to have been stranded with the full 11 gallon and a bit in the filler pipe as well having filled up within the last 10 mile, that engine will do 35 to 40 to a gallon, how many hours is that sitting still?. I dont know, I dont have the maths. The myths I am proposing for possible perusal is the one that says your better staying with the car/vehicle and awaiting rescue. In the Truck, I am suggesting thats just dandy, because I can last up to three days on one tank of fuel doing 55mph, so by the time I send out a call for rescue, they will come and find me in plenty of time, and I would have had food and drink on board anyway. In the car?. Even with rationing of fuel to use of 10 mins per hour to top up the heat, will that tank last 24 hrs in that situation?. What if you are stranded miles from anywhere?. In UK, there isnt many places you dont get some form of Phone coverage, so getting a rescue from Mountain Rescue by helicopter would not be impossible if it became life threatening, but elsewhere in the world?. And of course, you would have to get past the fact I aint that daft to have not gone prepared, and if I am on a road that hasnt seen traffic for over an hour, and the weather is getting cr@ppy, I am off to somewhere more populated and considering my need to be on a depopulated mountain pass at that time. Or not have gone in the first place, because I listen carefully to weather warnings?. |
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Post by the light works on Dec 30, 2017 12:09:46 GMT
in my truck, about an hour before the engine cools off too much to keep the cab warm. but at the road closure mentioned, it took barely a quarter tank to keep the cab warm all night. because yes, since they were saying vehicles with four wheel drive or chains were allowed to go through, we didn't make an immediate run for a hotel, and so couldn't get a room. My car is not supposed to be all that insulated, so in a real cold snap, will cool down within quarter of an hour, The heavy goods night cabs, they are more insulated, especially those with night heaters, the night heater may only need to cycle once every hour as you say to top up the heat, its warmer than say a Caravan, but noisier than trying to sleep though an earthquake if you get parked next to one that rattles badly. The question I am proposing here, if anyone knows, on a full tank of fuel, in a minus 10 to -20 Celsius stranded in a snow bank situation, on say three quarters of an average tank, how long before the fuel would run out?. On average, my sub 2ltr engine with a 11 gallon {uk not short ton USA gallon, this is 8 pints to a gallon] tank of fuel, sitting idling at perhaps just short of 1,000 rpm maybe 1100 rpm with fan and a/c [reduces moisture so windows dont steam up] running, if I am lucky enough to have been stranded with the full 11 gallon and a bit in the filler pipe as well having filled up within the last 10 mile, that engine will do 35 to 40 to a gallon, how many hours is that sitting still?. I dont know, I dont have the maths. The myths I am proposing for possible perusal is the one that says your better staying with the car/vehicle and awaiting rescue. In the Truck, I am suggesting thats just dandy, because I can last up to three days on one tank of fuel doing 55mph, so by the time I send out a call for rescue, they will come and find me in plenty of time, and I would have had food and drink on board anyway. In the car?. Even with rationing of fuel to use of 10 mins per hour to top up the heat, will that tank last 24 hrs in that situation?. What if you are stranded miles from anywhere?. In UK, there isnt many places you dont get some form of Phone coverage, so getting a rescue from Mountain Rescue by helicopter would not be impossible if it became life threatening, but elsewhere in the world?. And of course, you would have to get past the fact I aint that daft to have not gone prepared, and if I am on a road that hasnt seen traffic for over an hour, and the weather is getting cr@ppy, I am off to somewhere more populated and considering my need to be on a depopulated mountain pass at that time. Or not have gone in the first place, because I listen carefully to weather warnings?. that was an hour, idling, before the engine gets too cool to keep the cab warm. okay, it's not really that bad, but it takes it 4 miles at road speed to warm up the engine enough to register on the gauge. I've left it idling for an hour to defrost the windshield before, without affecting my fuel economy. I know one of my instructors in college left her lights on and had to get jump started, and then forgot to shut the car off after an hour, and ran whatever fuel was in the tank out by the next day. taken from my maths side, the average car in the US has a 300 mile fuel tank, so well over 10 hours run time, considering they can do that 300 miles at city speeds. from an anecdotal evidence side, the people I've heard of getting lost in the snow seem to run out of gas within two days |
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Post by GTCGreg on Dec 30, 2017 15:27:41 GMT
From the U.S. Department of Energy website energy.gov/eere/vehicles/fact-861-february-23-2015-idle-fuel-consumption-selected-gasoline-and-diesel-vehiclesSo if you have a large (by U.S. standards) gasoline fueled car, it consumes just under 0.4 gallons per hour at idle. That means that if you have about half a tank of fuel (around 10 gallons) you can idle the engine for 25 hours. A compact car uses about half the fuel but also has a smaller tank. It would appear from the chart that diesel and gasoline cars consume about the same amount of fuel at idle. Larger diesel trucks seem to consume less than gasoline fueled trucks.  |
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Post by the light works on Dec 30, 2017 16:03:17 GMT
From the U.S. Department of Energy website energy.gov/eere/vehicles/fact-861-february-23-2015-idle-fuel-consumption-selected-gasoline-and-diesel-vehiclesSo if you have a large (by U.S. standards) gasoline fueled car, it consumes just under 0.4 gallons per hour at idle. That means that if you have about half a tank of fuel (around 10 gallons) you can idle the engine for 25 hours. A compact car uses about half the fuel but also has a smaller tank. It would appear from the chart that diesel and gasoline cars consume about the same amount of fuel at idle. Larger diesel trucks seem to consume less than gasoline fueled trucks. I would expect fuel injection and the various forms of supercharging to make a difference - a car with a carburetor flows fuel in proportion to airflow, and has to flow air at a certain rate to keep fuel from puddling in the intake. therefore the cross section of the carburetor would determine the fuel flow. with fuel injection, the system only needs to keep enough fuel flowing to keep the engine from stopping, therefore, enough to get the correct mixture around the spark plugs, or to ignite under compression; which could be less than premixing the fuel and air would require, but would definitely be less in a smaller displacement block than a larger one. hence, an engine that gets its horsepower from pre-compressing the air, or get it from revving higher, would use less fuel at idle. than one that didn't. |
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Post by GTCGreg on Dec 30, 2017 16:34:20 GMT
I would expect fuel injection and the various forms of supercharging to make a difference - a car with a carburetor flows fuel in proportion to airflow, and has to flow air at a certain rate to keep fuel from puddling in the intake. therefore the cross section of the carburetor would determine the fuel flow. with fuel injection, the system only needs to keep enough fuel flowing to keep the engine from stopping, therefore, enough to get the correct mixture around the spark plugs, or to ignite under compression; which could be less than premixing the fuel and air would require, but would definitely be less in a smaller displacement block than a larger one. hence, an engine that gets its horsepower from pre-compressing the air, or get it from revving higher, would use less fuel at idle. than one that didn't. I doubt it would make that much difference between fuel injection and carburated. At idle, the cross section of the carburetor doesn't really matter much since about 95% of it is being blocked by the closed throttle plate. Also, with a carburetor, fuel isn't forced into the airstream. It is "sucked" into the airstream by the pressure drop of the venturi. Low airflow = low fuel flow. No airflow = no fuel flow. As for superchargers, I don't think they do much at idle. Besides, when was the last time you saw a car with a carburetor? |
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Post by the light works on Dec 30, 2017 22:04:04 GMT
I would expect fuel injection and the various forms of supercharging to make a difference - a car with a carburetor flows fuel in proportion to airflow, and has to flow air at a certain rate to keep fuel from puddling in the intake. therefore the cross section of the carburetor would determine the fuel flow. with fuel injection, the system only needs to keep enough fuel flowing to keep the engine from stopping, therefore, enough to get the correct mixture around the spark plugs, or to ignite under compression; which could be less than premixing the fuel and air would require, but would definitely be less in a smaller displacement block than a larger one. hence, an engine that gets its horsepower from pre-compressing the air, or get it from revving higher, would use less fuel at idle. than one that didn't. I doubt it would make that much difference between fuel injection and carburated. At idle, the cross section of the carburetor doesn't really matter much since about 95% of it is being blocked by the closed throttle plate. Also, with a carburetor, fuel isn't forced into the airstream. It is "sucked" into the airstream by the pressure drop of the venturi. Low airflow = low fuel flow. No airflow = no fuel flow. As for superchargers, I don't think they do much at idle. Besides, when was the last time you saw a car with a carburetor? I'd have to talk to a gearhead to confirm it, but I think a fuel injected car doesn't have to add fuel to ALL the air in the cylinder at idle - whereas a carburetor or throttle body injector system does - and did you miss the part where I said there is a minimum airflow to keep the carburetor working efficiently? I still think a fuel injected car can idle more fuel efficiently than a carbureted engine, because the fuel is managed instead of just delivered. that would be a question for a mechanic though. and you interpreted my comment about supercharging exactly backwards. a supercharged car has a smaller engine than a naturally aspirated engine of the same horsepower - meaning less air and less fuel at idle. - same thing with a higher revving engine: more horsepower out of a smaller box, so more efficient operation at idle than a low revving engine with the same peak horsepower. and for the last: today's Saturday, isn't it? |
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Post by GTCGreg on Dec 30, 2017 22:19:04 GMT
I doubt it would make that much difference between fuel injection and carburated. At idle, the cross section of the carburetor doesn't really matter much since about 95% of it is being blocked by the closed throttle plate. Also, with a carburetor, fuel isn't forced into the airstream. It is "sucked" into the airstream by the pressure drop of the venturi. Low airflow = low fuel flow. No airflow = no fuel flow. As for superchargers, I don't think they do much at idle. Besides, when was the last time you saw a car with a carburetor? I'd have to talk to a gearhead to confirm it, but I think a fuel injected car doesn't have to add fuel to ALL the air in the cylinder at idle - whereas a carburetor or throttle body injector system does - and did you miss the part where I said there is a minimum airflow to keep the carburetor working efficiently? I still think a fuel injected car can idle more fuel efficiently than a carbureted engine, because the fuel is managed instead of just delivered. that would be a question for a mechanic though. and you interpreted my comment about supercharging exactly backwards. a supercharged car has a smaller engine than a naturally aspirated engine of the same horsepower - meaning less air and less fuel at idle. - same thing with a higher revving engine: more horsepower out of a smaller box, so more efficient operation at idle than a low revving engine with the same peak horsepower. and for the last: today's Saturday, isn't it? You could be right on both counts. I really don't know, but I'd say the 0.39 GPH figure for the full size car and 0.16 for the compact is a good place to start. These figures are for engine displacement, not horsepower. The 0.39 GPH is for a 4.6 liter engine and the 0.16 (compact car) is 2 liter. As for when the last time you saw a carbureted car, OK, excluding your jeep, when was the last time? |
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Post by the light works on Dec 30, 2017 22:51:05 GMT
I'd have to talk to a gearhead to confirm it, but I think a fuel injected car doesn't have to add fuel to ALL the air in the cylinder at idle - whereas a carburetor or throttle body injector system does - and did you miss the part where I said there is a minimum airflow to keep the carburetor working efficiently? I still think a fuel injected car can idle more fuel efficiently than a carbureted engine, because the fuel is managed instead of just delivered. that would be a question for a mechanic though. and you interpreted my comment about supercharging exactly backwards. a supercharged car has a smaller engine than a naturally aspirated engine of the same horsepower - meaning less air and less fuel at idle. - same thing with a higher revving engine: more horsepower out of a smaller box, so more efficient operation at idle than a low revving engine with the same peak horsepower. and for the last: today's Saturday, isn't it? You could be right on both counts. I really don't know, but I'd say the 0.39 GPH figure for the full size car and 0.16 for the compact is a good place to start. These figures are for engine displacement, not horsepower. The 0.39 GPH is for a 4.6 liter engine and the 0.16 (compact car) is 2 liter. As for when the last time you saw a carbureted car, OK, excluding your jeep, when was the last time? you forget where I live. there are still a lot of 80s cars on the road out here. |
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Post by silverdragon on Dec 31, 2017 8:54:54 GMT
I'd have to talk to a gearhead to confirm it, but I think a fuel injected car doesn't have to add fuel to ALL the air in the cylinder at idle - whereas a carburetor or throttle body injector system does - and did you miss the part where I said there is a minimum airflow to keep the carburetor working efficiently? I still think a fuel injected car can idle more fuel efficiently than a carbureted engine, because the fuel is managed instead of just delivered. that would be a question for a mechanic though. and you interpreted my comment about supercharging exactly backwards. a supercharged car has a smaller engine than a naturally aspirated engine of the same horsepower - meaning less air and less fuel at idle. - same thing with a higher revving engine: more horsepower out of a smaller box, so more efficient operation at idle than a low revving engine with the same peak horsepower. and for the last: today's Saturday, isn't it? You could be right on both counts. I really don't know, but I'd say the 0.39 GPH figure for the full size car and 0.16 for the compact is a good place to start. These figures are for engine displacement, not horsepower. The 0.39 GPH is for a 4.6 liter engine and the 0.16 (compact car) is 2 liter. As for when the last time you saw a carbureted car, OK, excluding your jeep, when was the last time? Yesterday here, OK, so I live close to a guy who keeps older vehicles running, but even past that, I did pass an older Mk 1 Capri yesterday, I was following it for a while, I could smell the exhaust before I saw it?. Being I used to own one, at idle, my Mini, Cavalier, Escort, Lada, and various other Carbed cars all ran at about 1000 to 1100 RPM at idle most of the time, 1200 to 1300 on choke, 1500 on "Cone on you swine show some life" extreme cold start days. My current car runs at 12-1300 only on a cold cold engine, it drops to 900rpm when warm, after about 5 mins on the coldest I drive it at, even under load of A/C and fan, because its backs off the injection to just whats needed to prevent stalling. Carbed cars can not do that at all. They have a pre-set idle setting thats worked out "On average". The ECU on my car measures many things, including the temp of the air going in, and alters the fuel injection to suit, so that on a cool day with dense air its using less fuel to idle than a warm day with damp air, it reacts to that by trying to get the needle to stick to the pre-set RPM for idle speed, whereas carbed cars just run faster on cold dense air than they do on warm air and have a tendency to run rich on cold days because of choke. My current modern [ish] car has an exhaust sensor that works out if the fuel has been to rich, and backs off the fuel, same as most injection ECU EMU cars?. On the cars that have the turbo, compared to similar engine size without turbo, they consume more fuel on idle, because you never truly shot down a turbo, it takes a while to spool up to working pressure, but its still spinning al idle, and that takes away some of the power, so the engine is harder to turn. Not much... but maybe a small cup full per hour at idle?. [dependant on size...] I have heard some mechanics of good standing state that a turbo that creates anything less than 10lbs of pressure is not worth running at all. |
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Post by GTCGreg on Dec 31, 2017 17:15:11 GMT
So are we discussing how long a tank of gas could keep you warm in the typical automobile, or are we discussing how long a tank of gas could keep you warm in 99 percent of the cars that are no longer on the road?
Unless you live in some Third World country or apparently Oregon, most cars do not have carburetors.
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Post by the light works on Dec 31, 2017 17:18:53 GMT
So are we discussing how long a tank of gas could keep you warm in the typical automobile, or are we discussing how long a tank of gas could keep you warm in 99 percent of the cars that are no longer on the road? we are discussing what factors affect how long a car can idle on a tank of fuel. I guess once we exhaust that, we could discuss whether there are factors that affect how efficiently cars transfer heat from the fuel to the cabin. |
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Post by silverdragon on Jan 1, 2018 10:41:48 GMT
So are we discussing how long a tank of gas could keep you warm in the typical automobile, or are we discussing how long a tank of gas could keep you warm in 99 percent of the cars that are no longer on the road? Unless you live in some Third World country or apparently Oregon, most cars do not have carburetors. Most or many, but not yet all?. Greg, "Not 100 mile from your borders", or something like that, there is Cuba....  You are right to state that close on 100% of all "new" cars are fuel injection, however, this show goes world wide, and we have to address the fact that in some countries, especially in the rural parts where snow could drift yard high, they still have many more carburetted cars than fuel injected, from older stock, think India, Pakistan, and any country that ends ***stan  in all probability, and, in UK, there is a historic fleet of older cars that grace our streets to remind us of the days when they used to build cars to last more than the warranty period, the days when you could tell cars apart 500yds away, and the days when you could tell some just by the smell of the exhaust smoke.  No everything wasnt "Better" back then, some of them were notoriously fickle to tickle into life in the mornings, and part of that is I still carry a more comprehensive tool kit than just a credit card with the name of a tow company on it.? Being able to fettle an old Brit Bike into life and keep it running used to be part of the driving licence... I note with wry humour that they re-introduced questions on vehicle maintenance back into the driving test recently. There exists something we all know as the All-Agro, the "allegro", which I think is also Italian for "fast" in Music, which is ironic, because the all-agro is anything but fast, ask anyone who had the misfortune how you could double the price of one, and they will smile wistfully and reply fill the tank with fuel?.  Those things were so damn unreliable, if one got stranded in the snow, if it had its usual trouble getting started, it would probably be better to set the thing on fire and keep warm around the bonfire?. At least that way you would get some warmth out of the fuel... The things were so bad no one used to fill the tank all the way, because petrol is expensive, and no one trusted them that much. |
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Post by GTCGreg on Jan 1, 2018 15:01:53 GMT
Don't think you are going to freeze to death in Cuba even if you do get stranded.
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Post by the light works on Jan 1, 2018 16:25:40 GMT
So are we discussing how long a tank of gas could keep you warm in the typical automobile, or are we discussing how long a tank of gas could keep you warm in 99 percent of the cars that are no longer on the road? Unless you live in some Third World country or apparently Oregon, most cars do not have carburetors. Most or many, but not yet all?. Greg, "Not 100 mile from your borders", or something like that, there is Cuba.... You are right to state that close on 100% of all "new" cars are fuel injection, however, this show goes world wide, and we have to address the fact that in some countries, especially in the rural parts where snow could drift yard high, they still have many more carburetted cars than fuel injected, from older stock, think India, Pakistan, and any country that ends ***stan in all probability, and, in UK, there is a historic fleet of older cars that grace our streets to remind us of the days when they used to build cars to last more than the warranty period, the days when you could tell cars apart 500yds away, and the days when you could tell some just by the smell of the exhaust smoke. No everything wasnt "Better" back then, some of them were notoriously fickle to tickle into life in the mornings, and part of that is I still carry a more comprehensive tool kit than just a credit card with the name of a tow company on it.? Being able to fettle an old Brit Bike into life and keep it running used to be part of the driving licence... I note with wry humour that they re-introduced questions on vehicle maintenance back into the driving test recently. There exists something we all know as the All-Agro, the "allegro", which I think is also Italian for "fast" in Music, which is ironic, because the all-agro is anything but fast, ask anyone who had the misfortune how you could double the price of one, and they will smile wistfully and reply fill the tank with fuel?. Those things were so damn unreliable, if one got stranded in the snow, if it had its usual trouble getting started, it would probably be better to set the thing on fire and keep warm around the bonfire?. At least that way you would get some warmth out of the fuel... The things were so bad no one used to fill the tank all the way, because petrol is expensive, and no one trusted them that much. when they asked me to describe my trade in when I bought the truck, I told them "'93 vandura, 300,000 miles, premium audio package, new tires, and half a tank of gas. |
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Post by GTCGreg on Jan 1, 2018 16:39:46 GMT
when they asked me to describe my trade in when I bought the truck, I told them "'93 vandura, 300,000 miles, premium audio package, new tires, and half a tank of gas. I know what you mean. I had a few vehicles that doubled in value every time you filled the tank. |
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Post by the light works on Jan 1, 2018 16:45:36 GMT
when they asked me to describe my trade in when I bought the truck, I told them "'93 vandura, 300,000 miles, premium audio package, new tires, and half a tank of gas. I know what you mean. I had a few vehicles that doubled in value every time you filled the tank. if my dad was still driving his pickup during the GW Bush administration, it would have picked up over $200.00 value from full tanks. as it was, when he traded that one in, they siphoned the gas from it to the new one. when I was at the gas station, I filled a few RV haulers that had 100 gallon pack tanks. that was back when most gas pumps only displayed two digits on each side of the decimal. |
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Post by silverdragon on Jan 2, 2018 9:22:44 GMT
I know what you mean. I had a few vehicles that doubled in value every time you filled the tank. if my dad was still driving his pickup during the GW Bush administration, it would have picked up over $200.00 value from full tanks. as it was, when he traded that one in, they siphoned the gas from it to the new one. when I was at the gas station, I filled a few RV haulers that had 100 gallon pack tanks. that was back when most gas pumps only displayed two digits on each side of the decimal. The first time I filled up a Artic's tanks, I did some maths, and worked out just how much heavier the fuel load was over the gross load weight of my Ford Escort.. the system then was drive between two pumps and fill both sides at the same time from different pumps, it still felt like it took half a bloody hour to fill it all the way up... twin 55 UK gallon tanks I then had a look at the receipt for the diesel, and tried to work out how long it would take for me to earn that much. It was quite a few years before I could afford to drive a vehicle worth more than the diesel in a full day cab Artic semi's tanks. But then, if you are doing less than 9 mile per gallon even when empty, and thats a full weeks fuel, yeah, it has to be a lot of fuel?. I have since driven many bigger tramping rigs, sleeping quarters over a huge "Belly tank" that holds twice as much again. My current car is not worth the diesel in those tanks when full. |
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Post by GTCGreg on Jan 2, 2018 13:27:34 GMT
My wife's Excursion has a 45 gallon tank. When gas was up near $4 a gallon, it took over $150 to fill it up. Now, with the lower gas prices, it seems like a bargain to only pay $100 for a trip to the gas station.
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Post by c64 on Jan 2, 2018 22:01:01 GMT
My wife's Excursion has a 45 gallon tank. When gas was up near $4 a gallon, it took over $150 to fill it up. Now, with the lower gas prices, it seems like a bargain to only pay $100 for a trip to the gas station. My gas tank is rated 70 liter - which is a lot less than your 45 gallons - but it still can cost €100 or more - which is much more than your $100  |
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Post by c64 on Jan 2, 2018 22:15:04 GMT
Fun fact:
In the past, the owner of a car knew that you never, ever top off the tank in summer and then park the car in the sun.
Nowadays it is different. Due to serious gas spills, VW had redesigned the gas tank of my car in 1992 so there is a reserve space you can't fill up. The tank is bulkier and the refueling pipe enters the tank in the middle to make sure there is always plenty of air trapped inside.
While my car still has the classic pre-1992 body, it has the new gas tank design. The Poles love the new design. When you shake the car, you can continue to refuel. Poles I had met at a construction site claim that the gas tank can hold 130 liters instead of the rated 70 liters. Enough to reach any construction site in Germany and return home with their cheap Polish gas.
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in all probability, and, in UK, there is a historic fleet of older cars that grace our streets to remind us of the days when they used to build cars to last more than the warranty period, the days when you could tell cars apart 500yds away, and the days when you could tell some just by the smell of the exhaust smoke. 
