Natural Gas for cars. Why isn't it more readily available

[Hawkstrong16]

Like the title says. Any thoughts as to why it is not more common, it is considerably cheaper then Gasoline and you can go farther on less. And the only thing you have to do to your car is change your fuel tank and lines.

 

So I'm just wondering what everybody's thoughts on this matter are?

 

Is it a good idea to be making Natural gas more readily available for everybody?

Or do you think its a bad idea. Feel free to express yourselves freely. But......BE NICE!

 

And I think that it would be a great idea to have Natural Gas. It would be great to be able to use my Yukon XL. My family could then afford to go camping more with our big camper(Family of 7 so don't yell because we have a big car. we need it) But mostly they sit and rot in our driveway.

 

So give me your thoughts

 

EDIT: Could a mod please change the name of the thread to Alternative fuels

[e-varmint]

Hmmmm. I wonder if you could just run a line from your house and "gas up" in the driveway. It wouldn't help you on a long trip, but it would be great for commuting to work or shorter trips.

[Hawkstrong16]

Actually that would work. I've talked about it with Dad and my Grandfather.

 

But my main line of thought was not everybody has Natural Gas at their house.

[Bimmerman]

There's a whole lot more to converting a car to run on natural gas than you let on. First and foremost is engine tuning; different fuels burn differently, camshaft timing may need altering, injection duration and timing, firing angle, etc all need to be considered. The engine must also be changed to run a significantly higher compression ratio, i.e. new pistons at a minimum ($1k), rods also to be smart, not to mention the need for a new fuel tank. This isn't cheap nor easy to do, and requires much custom work to be done.

 

Secondly, converting the car will play havoc on the emissions system. Catalytic converters, urea injection, particulate filters, etc are not all used on the same car for good reason- the chemical byproducts of the combustion reaction are not identical for gasoline, E85, hydrogen (not fuel cell shenanigans), diesel, natural gas, etc.

 

Thirdly, the cost of filling up the tank is lower, true. However, natural gas has significantly less energy by mass and volume, so you will end up burning more fuel to cover the same distance and achieve the same performance. Depending on the fuel cost, it will be difficult to achieve a break even point (look at E85!). Not to mention, the process of refining and processing it is very very complicated.

 

Why is it not widely available? There is no demand for it. Gasoline works, is cheap, is clean, and has the necessary support structure to make it work. Diesel does too. Fuel cells will not pick up until there is a hybrid type gas/hydrogen combustion car to increase the demand for a hydrogen filling station infrastructure. Same goes for electric cars, same goes for E85, same goes for natural gas.

 

It is NOT possible to simply run a fuel line from your house meter to your garage to fill your tank. Your engine needs it to be liquified and enriched (i.e. significantly unprocessed) to be able to run without SIGNIFICANT modifications to your engine, fuel system, cooling system, etc. People who say otherwise are selling you snake oil.

 

A 15 gallon tank of natural gas at atmospheric pressure (what it would be if you run a fuel line to your gas tank, though yours is 45gallon) will make you move, oh, 3 feet or so. A suburban/yukon, probably 3 inches. You would need a modified fuel tank to hold highly compressed natural gas to make it effective and give the car a usable range. The problem with that is threefold- weight, durability/reliability, accident proofing. Think about what happens if a compressed can of hairspray is punctured or heated.....do you want that to happen in your car?

 

Everyone clamoring for new alternative fuels really doesn't see anything other than lower cost to fill the tank; nobody actually looks at the whole picture. Are people really that averse to paying for something that is already stupid cheap? The modifications to make your car run on NG will easily cost thousands of dollars, and the payback period for that, despite the low cost per tank, will mean you will never break even compared to just sucking it up and paying the $2 a gallon. Run the numbers, it doesnt make sense at all to change to an inferior fuel, despite the cheaper per tank cost.

[Q]

Man, Bimmerman, your posts are always so informative.

[Hawkstrong16]

Umm. After talking to my mechanic(who did this to an old car he had) and researching this.

You wont have to make big changes to your engine, you wont have to make any. You need a pressure tank on your car. and pressure lines. I believe it was a 93 Blazer he did it to. I forget how much it cost for the tank and lines. I'll ask next time I'm there, But he still runs it. The body is almost gone but the engine runs like new on NG

 

Also, Car company's need to start making it an option on new cars. You can get Gasoline, or Natural gas, for the new car you buy. Then people have a choice as to what they want. If it doesn't work, oh well it was worth a try.

[narfblat]

We should also keep supply and demand in mind, as that could greatly increase the price of natural gas if it becomes popular.

 

Umm. After talking to my mechanic(who did this to an old car he had) and researching this.

You wont have to make big changes to your engine, you wont have to make any. You need a pressure tank on your car. and pressure lines. I believe it was a 93 Blazer he did it to. I forget how much it cost for the tank and lines. I'll ask next time I'm there, But he still runs it. The body is almost gone but the engine runs like new on NG.

 

Does that car pass inspection? What will happen if that car is in an accident?

[Hawkstrong16]

It passed inspection until 2008 when the rust got so bad. The engine is fine though. And it did pass.

I think he said something about taking it to his fathers farm, until it gets to the point where he just swaps out the Engine and fuel tank with something else

[Bimmerman]

Is it doable to retrofit it? Yes. Is it smart? No. I can absolutely guarantee that despite your mechanic's car passing inspection and/or emissions (not sure on PA inspections or emissions laws), the engine is running absolutely terribly. It may seem fine, but it is not making anywhere near peak power, has what I would imagine to be extremely poor mileage, etc etc.

 

There are many reasons the main car companies do NOT do natural gas. You can buy cars in Europe that can run on LPG- liquified petroleum gas. This is not the same as true natural gas, and the cars run slower, poorer, and not a lot cheaper, so it is rare to see them and fuel stations with the stuff.

 

Why don't we use NG as a fuel?

 

Accidents and high pressure tanks. Bad combination.

 

Emissions results higher than gasoline

 

Engine needs to be designed around the fuel. Any fool with tools can retrofit something to work, but to do it right costs time, money, and designing it from inception to use that fuel. This is why diesels and gasoline engines are different, why hydrogen internal combustion (not fuel cells) is different than gasoline, etc.

 

NG is not prevalent enough to justify the cost of using it as a fuel. There is no refueling infrastructure in the US, and the cost associated with filling a tank on legit vehicle NG is more expensive than you think, and much more complicated than simply running a line from your house gas pipes to your garage.

 

Storage: compressed NG tank is explosive under the right circumstances, heavy, bulky, and requires sophisticated filling mechanism. You want a filling device that is leakproof, durable, and fireproof. Good luck installing one of those in your garage.

 

Mileage: Less energy per mass than gasoline means you burn more to make the same power and go the same distance. Snakeoil does not trump simple thermodynamics.

 

Don't you think that if this was a feasible concept it would have taken off in the past century?

[Hawkstrong16]

Don't you think that if this was a feasible concept it would have taken off in the past century?

 

This is true. As much as I wish it were not.

 

Hopefully we can come up with a feasible plan for alternative fuels sometime in the near future.

 

What types of fuels are there that you know of that could work? Any ideas? (Other then Hydrogen)

And seriously.. We need to be making more cars with a 4 cylinder Diesel. 50+ MPG on some of them. How come only the Germans make them? (idk who all makes them now anymore)

[Bimmerman]

This is true. As much as I wish it were not.

 

Hopefully we can come up with a feasible plan for alternative fuels sometime in the near future.

 

What types of fuels are there that you know of that could work? Any ideas? (Other then Hydrogen)

And seriously.. We need to be making more cars with a 4 cylinder Diesel. 50+ MPG on some of them. How come only the Germans make them? (idk who all makes them now anymore)

 

What I envision, aside from more and more diesels and diesel hybrids (far better and more fuel efficient than gas hybrids) are hybrid gas and hydrogen internal combustion cars. This provides the necessary step between full gas/hybrids and the fuel cell future everyone is talking about. The fact is that no matter how cheap the technology becomes, there needs to be a vehicle that bridges the gap and can run on both hydrogen and gasoline as an internal combustion fuel. As far as I am aware, only BMW makes such a hybridized car, and it's quite expensive. If these take off, I think the infrastructure would then be implemented, and 20-30 years afterward the fuel cell idea will take off.

 

Aside from that admittedly rather long shot, I see more and more diesels, diesel hybrids, and HCCI engines. What will be the biggest block to the implementation of smaller four cylinder diesels, despite their high MPG, is the fact that they are, well.....slow. Modern diesels are quite fuel efficient, low emissions, and do not stink like the big diesel trucks (whole other animal). However....they are slow. Very few manufacturers (BMW, M-B) make performance diesels, which are sadly the only ones with a prayer of not being a sales flop here in the US. Gas is cheap, diesel not so much, and until prices are similar to where they are in Europe ($1.50 or so per liter, so $6 per gallon), small efficient diesels will not catch on.

[Q]

Again I agree with you, because I think that the diesel has the best chance of offering a viable alternative to cars that burn petroleum because they're able to use biodiesel. Naturally, those small diesels will all have to be turbocharged to be worth a damn.

[Hawkstrong16]

Yeah I also have to agree. To bad more people can't be like me and not care about how fast it is. I just need something I can afford to even start. I know too many people who say

"Oh I need a big truck... Wait you want me to take it out in the snow? Sorry I can't do that, I only have $600 snow tires that I use all year."

 

Who all still makes Diesel anymore? I mean for cars and small pickups

[Bimmerman]

I'm of the opposite opinion; I don't care how much fuel I burn or emissions I create, I want to go fast NOW. My budget and my cars don't exactly live up to my wishes as of yet.

 

In any case, manufacturers who build good diesels in the US:

VW (Golf/Jetta TDI)

Audi

BMW (335d, 535d, X5 3.5d....same biturbo 3L I6 diesel motor, 36 mpg, stupid fast and does burnouts. WIN)

Mercedes (Blutec)

 

Pickups....I dont follow or care about. I won't ever buy one except to trailer race cars, so it's not like they feature prominently in my consciousness. That....and most people who drive big trucks don't need them i.e. poseurs.

 

As far as trucks driving year round on snow tires go, or thinking you need a truck or AWD (mpg killer, that) for snow....no thanks. Snow exists to justify RWD cars; if you're not sliding around turns steering with your foot, then what are we on this planet for?

 

If I could afford one, a 335d would be on top of my list for a daily driver. It won't ever make back the sticker premium (unless you're like me and keep cars till the wheels fall off), but the engine is far better suited to daily use than comparable non diesel motors. 286 hp, 420 lb-ft torque, 36 mpg, what's to lose?

[Hawkstrong16]

I'm of the opposite opinion; I don't care how much fuel I burn or emissions I create, I want to go fast NOW. My budget and my cars don't exactly live up to my wishes as of yet.

 

I'd only really do that as a weekend type thing, for fun. The rest of the time I want high MPG

 

In any case, manufacturers who build good diesels in the US:

VW (Golf/Jetta TDI)

Audi

BMW (335d, 535d, X5 3.5d....same biturbo 3L I6 diesel motor, 36 mpg, stupid fast and does burnouts. WIN)

Mercedes (Blutec)

I miss the VW Rabbit pickup, those are pretty sweet.

 

Pickups....I dont follow or care about. I won't ever buy one except to trailer race cars, so it's not like they feature prominently in my consciousness. That....and most people who drive big trucks don't need them i.e. poseurs.

 

The only reason I care about the pickups is I need one to haul a lawnmower around in the summer and I would like something with 4X4 in the winter(I live in central PA, sometimes the snow gets pretty bad other times it not bad at all). And it would be a small pickup. Like a Toyota Tacoma, Mozda B Series. GMC S15/Sonoma, etc. Something with a 4 cylinder. or a small V6 at most.

Other then that I'll drive a regular car

 

And I hate people who drive big trucks for no reason. Yes big trucks are cool. But only get them if you have a really good reason to. And the snow tires in the summer is pointless because they just grind away on hot asphalt and are gone by winter

 

As far as trucks driving year round on snow tires go, or thinking you need a truck or AWD (mpg killer, that) for snow....no thanks. Snow exists to justify RWD cars; if you're not sliding around turns steering with your foot, then what are we on this planet for?

 

I'm of two minds on this one. Its one thing to have fun with it sometimes(Don't get me wrong I love doing it) But I would rather feel safe knowing I have 4WD just in case something goes wrong or I get stuck.

I do know that 4WD with kill MPG Its also a good thing to have its great if your pulling crap around. That and it only takes it down by 1-3 MPG so its not a huge deal.

 

If I could afford one, a 335d would be on top of my list for a daily driver. It won't ever make back the sticker premium (unless you're like me and keep cars till the wheels fall off), but the engine is far better suited to daily use than comparable non diesel motors. 286 hp, 420 lb-ft torque, 36 mpg, what's to lose?

 

I have to agree with this

[Bimmerman]

My weekend car is a race prepped car, my DD is an AWD subaru. The AWD does come in handy during winter, as I can do wicked rally drifts around turns and other cars in deep snow (CO winters can be nuts). Both cars are entertaining in their own way.

 

Ironically, both my racecar and my DD get better MPG than most people do, and I am very forceful with the loud pedal. My racecar's not slow either, it's just very lightweight for its power level, and geared appropriately.

 

A pickup is very useful for that kind of thing, but have you considered getting an AWD car that can tow a small utility trailer? We have one of those for the Scoobaru and have never been let down. Traded our Suburban for the combo in point of fact.

 

That said, the Toyota Tacomas with the V6 are very nice trucks, a good friend of mine has one. It's damn near unstoppable off road and quite comfy on road to go skiing in. 15 mpg is a downer though. If you only use the truck when needed, and not as a DD, it is definitely useful to have as a utility vehicle. My grandfather does exactly this; DD's a Miata or Camry depending on the day, uses the truck to do the heavy stuff. To date, he bought the Ford Ranger new in 1998 and it has all of 12k miles on it. Worth thinking about if your budget can afford a used truck and the insurance to lay it up when it's not needed.

 

As far as AWD/4WD/RWD for snow is concerned, the most important thing is driver training. I'm not a fool behind the wheel, and have taken winter performance driving classes and am working towards my wheel to wheel racing license. For most people, the added safety margin of A/4WD is a huge plus, and is for me too. RWD's just more fun to me. That said, see above comments of driving the piss out of the Subaru. Studded winter tires, AWD, ABS, and that car is literally unstoppable, even where and when some trucks are. Best winter car I've ever had.

[Tommycat]

I like Bimmerman, aside from the cars we choose for our loud pedal play we have similar thoughts. If I could get an electric car that performs near as well as a fueled car on a track, I'd probably look into it(gotta be able to do the number of laps and meet the lap times).

 

As for RWD in the snow, Well As long as you don't have an automatic you can go just about anywhere an AWD can(assuming similar ground clearance). Just a matter of, as you said, driver training. My grandfather's old 47 Chevy truck handled life on a farm and in the snow in Parker, CO for years. It didn't have 4WD. 4WD means you can get REALLLY stuck.

[Hawkstrong16]

My weekend car is a race prepped car, my DD is an AWD subaru. The AWD does come in handy during winter, as I can do wicked rally drifts around turns and other cars in deep snow (CO winters can be nuts). Both cars are entertaining in their own way.

 

I would like to get a Subaru, just can't afford one. My mom used to have an Outback but my older brother totaled it...

 

Ironically, both my racecar and my DD get better MPG than most people do, and I am very forceful with the loud pedal. My racecar's not slow either, it's just very lightweight for its power level, and geared appropriately.

 

Yeah most of the MPG problems are how the transmission is geared. We need to be seeing more 6 and 7 speed transmissions in everything. Not just the little cars. What kind of racecar do you have?

 

A pickup is very useful for that kind of thing, but have you considered getting an AWD car that can tow a small utility trailer? We have one of those for the Scoobaru and have never been let down. Traded our Suburban for the combo in point of fact.

 

I have considered a small car with a hitch, but I can't afford anything good enough, because whatever I get, I'm driving until it drives no more, then I'll piece it out and make more then what I paid. lol

I am waiting to hear back about a 86 Chevy S10 long bed 4WD, with the 2.8 V6 it will get about 19-21 MPG. And its only $300. Its a really good deal because the engine was replaced with one that only has about 60,000 miles on it.

Also the less passengers I can take the less my insurance is going to be. And this truck has bucket seats.

 

That said, the Toyota Tacomas with the V6 are very nice trucks, a good friend of mine has one. It's damn near unstoppable off road and quite comfy on road to go skiing in. 15 mpg is a downer though. If you only use the truck when needed, and not as a DD, it is definitely useful to have as a utility vehicle. My grandfather does exactly this; DD's a Miata or Camry depending on the day, uses the truck to do the heavy stuff. To date, he bought the Ford Ranger new in 1998 and it has all of 12k miles on it. Worth thinking about if your budget can afford a used truck and the insurance to lay it up when it's not needed.

 

Yeah I really wish I could find an affordable Toyota that isn't rusted to death. The 4 cylinder Tacomas are also great trucks. My dad used to have one and he got 28-30 MPG with it. And it was a 4WD and he used it as a DD. But on ebay I saw a 87 Toyota Tacoma go for $3700 and it was a 5 speed 4WD and it had the bed from a 1990 on it.

 

As far as AWD/4WD/RWD for snow is concerned, the most important thing is driver training. I'm not a fool behind the wheel, and have taken winter performance driving classes and am working towards my wheel to wheel racing license. For most people, the added safety margin of A/4WD is a huge plus, and is for me too. RWD's just more fun to me. That said, see above comments of driving the piss out of the Subaru. Studded winter tires, AWD, ABS, and that car is literally unstoppable, even where and when some trucks are. Best winter car I've ever had.

I agree with what you said here.

Thank you with all the useful info you have given me

 

This is something I just found when I was goofing around on youtube. Any thoughts? http://www.youtube.com/watch?v=WlHCOm4tLDU and also

 

I may try this sometime. After talking to someone I know about it. I mean I have nothing to lose right?

[JesusIsGonnaOwnSatan]

Why isn't it more readily available

 

because anyone who dares invent such things are taken out by oil company hired assassins wielding electromagnetic beam guns

[Bimmerman]

I like Bimmerman, aside from the cars we choose for our loud pedal play we have similar thoughts. If I could get an electric car that performs near as well as a fueled car on a track, I'd probably look into it(gotta be able to do the number of laps and meet the lap times).

 

Haha thanks! We enjoy different kinds of racing but we're all car guys, that's all that matters. Have you looked at the Tesla Roadster? It's....well...too expensive, but handles like an Elise, gets 250 miles per charge, and does 0-60 in 4ish. And ~.9g skidpad.

 

As for RWD in the snow, Well As long as you don't have an automatic you can go just about anywhere an AWD can(assuming similar ground clearance). Just a matter of, as you said, driver training. My grandfather's old 47 Chevy truck handled life on a farm and in the snow in Parker, CO for years. It didn't have 4WD. 4WD means you can get REALLLY stuck.

 

Yup. One of my fondest memories is going skiing in the mountains above Boulder, driving my dad's RWD 86 535i. Fishtailing that thing with studded snows and sandbags up a two lane mountain road with massive drop offs.....my god that was fun. Car handled it with aplomb.

 

because anyone who dares invent such things are taken out by oil company hired assassins wielding electromagnetic beam guns

 

Umm.....Clearly.

 

Yeah most of the MPG problems are how the transmission is geared. We need to be seeing more 6 and 7 speed transmissions in everything. Not just the little cars. What kind of racecar do you have?

 

Agreed. It's not just 6 and 7 speed transmissions though. The number of gears is secondary to both the final drive ration (differential) and the engine's powerband characteristics.

 

For example: my racecar, a not so stock 89 325i, has a 5 spd manual gearbox with a 4.10 LSD rear differential. I get 25 mpg on average when I'm split between highway and city. LSD, before the drug jokes start, means limited slip differential, and is a mechanical way of limiting wheelspin. Stock, my car had a 3.73 LSD.

 

Now, why this matters. My transmission is untouched. I have a 1:1 4th gear and a 0.82:1 5th. The 5th gear is otherwise called the overdrive. With the 3.73, this puts me at about 2500rpm at 75 mph. With the 4.10, I'm at 3500rpm at 75mph.

 

Now, considering how much faster I'm turning the motor, you would expect my highway mpgs to decrease, yes? WRONG. I average 27 mpg on the highway. Stock is basically identical. Why does this not change?

 

Answer: my engine's power characteristics. 3500rpm at 75 mph is right where my motor comes on cam and begins making power. This means I do not have to put my foot down to accelerate, I merely need to touch the throttle. At lower rpms, you are burning less in steady state, but are burning far more when you have to floor it to get the car to do anything. American V8s make power far lower down the rpm band than my engine does and are most economical at low rpms; this is a very engine specific thing.

 

Similarly, the claim that all cars are more efficient at 55mph and below is a bunch of bull. As anyone who has actually studied this, or driven more than one car on the highway has discovered, engines have different power delivery characteristics. It is absolutely true that above 60mph, aerodynamic drag becomes important. I am not disputing that. A car is only most efficient at 55mph when the engine is geared to be in its powerband in top gear at that speed. American muscle car? Yes, probably. Friend's 1994 BMW 325i? Hell no. I tested this very theory coming back from the middle of Utah. Constant 55-60 mph, 27-28 mpg. Constant 80-100 mph (Utah is boring as all hell), 30-33 mpg. I averaged 30 mpg at 90mph for three hours straight. It is all about where power is delivered in the rev range, and how efficient the car is both aerodynamically and mechanically.

 

I have considered a small car with a hitch, but I can't afford anything good enough, because whatever I get, I'm driving until it drives no more, then I'll piece it out and make more then what I paid. lol

I am waiting to hear back about a 86 Chevy S10 long bed 4WD, with the 2.8 V6 it will get about 19-21 MPG. And its only $300. Its a really good deal because the engine was replaced with one that only has about 60,000 miles on it.

Also the less passengers I can take the less my insurance is going to be. And this truck has bucket seats.

 

That sounds like a good deal, and will be especially good if you can do the work it will need yourself. Working on cars builds character!

 

Granted, it's a truck, but if you REALLY want to dissuade passengers from riding with you, and honestly, who wants to have trash, mess, food, and empty drinks from passengers, put harnesses in your car. NOBODY will want to ride with you.

 

Yeah I really wish I could find an affordable Toyota that isn't rusted to death. The 4 cylinder Tacomas are also great trucks. My dad used to have one and he got 28-30 MPG with it. And it was a 4WD and he used it as a DD. But on ebay I saw a 87 Toyota Tacoma go for $3700 and it was a 5 speed 4WD and it had the bed from a 1990 on it.

 

It seems to me that you are looking for a cheaper truck with good mpg's. If I were you, I would buy the best possible truck or car (subaru + trailer is easily cheaper than a $3700 truck) that you can for your budget. There's cheap, fast, and reliable. Pick two. Cheap and Fast isn't Reliable; Reliable and Cheap isn't Fast; Reliable and Fast isn't Cheap.

 

I agree with what you said here.

Thank you with all the useful info you have given me

 

This is something I just found when I was goofing around on youtube. Any thoughts? http://www.youtube.com/watch?v=WlHCOm4tLDU and also

 

I may try this sometime. After talking to someone I know about it. I mean I have nothing to lose right?

 

Don't waste your money or time. Seriously.

 

The amount of energy it takes to break the molecular bonds between the hydrogen and oxygen atoms is more than you will get by combusting the fuel. You will end up burning slightly more fuel, if any difference, and making zero impact on your emissions or fuel consumption.

 

Back to the NG issue from your OP-

 

I had a chance to talk with a colleague who has done research into using NG as a vehicle fuel. He did research on converting a diesel engine to use on CNG- compressed natural gas. Aside from the necessary conversions, such as adding spark plugs, changing intake manifold injection, lowering compression, and some other details, he was able to convert a diesel and run quite a few tests on the CNG powered engine.

 

He found that NG is quite suitable for a vehicle, with these key findings:

 

-Engine compression of 12:1 and higher (normal gasoline is 8-10:1)

-Gasoline engine blocks aren't suited to use as CNG, as the fuel burns much, much hotter and is injected at much, much higher pressures. Normal gasoline blocks will crack, fatigue, and break.

-Significantly cleaner emissions

-Significantly reduced usable range. On the order of 1/12th that of gasoline for comparable fuel amounts.

 

Unless the fuel cost is significantly cheaper, and it isn't likely to be if there is a nationwide infrastructure, CNG makes no sense from an economic viewpoint.

 

However, as is the case with Hybrid cars, there are many people who would pay more money for a car with lower emissions. Just like with a Prius, where the additional MPGs will never pay back the higher cost delta over a conventional car unless you drive it for 200k or so, so it would be with a CNG car. The fuel may cost less, but the car will cost more, resulting in a zero-sum game at best. However, you would have the cleanest emissions this side of a hydrogen internal combustion engine.

[Darth Avlectus]

Bimmerman...you are full of win. That's all I have to say about you.

 

So far as ethanol: if we continue this way...I can only see that we will be making corn (or whatever it is made from) shorter in supply and more expensive in the near to mid term future. And for what? I have my doubts as to how much effect it will *actually* have on the market.

 

So far as natural fuel...isn't mining it also a major concern for all the same reasons that mining pretty much anything else is?

[Hawkstrong16]

Agreed. It's not just 6 and 7 speed transmissions though. The number of gears is secondary to both the final drive ration (differential) and the engine's powerband characteristics.

 

For example: my racecar, a not so stock 89 325i, has a 5 spd manual gearbox with a 4.10 LSD rear differential. I get 25 mpg on average when I'm split between highway and city. LSD, before the drug jokes start, means limited slip differential, and is a mechanical way of limiting wheelspin. Stock, my car had a 3.73 LSD.

 

Now, why this matters. My transmission is untouched. I have a 1:1 4th gear and a 0.82:1 5th. The 5th gear is otherwise called the overdrive. With the 3.73, this puts me at about 2500rpm at 75 mph. With the 4.10, I'm at 3500rpm at 75mph.

 

Now, considering how much faster I'm turning the motor, you would expect my highway mpgs to decrease, yes? WRONG. I average 27 mpg on the highway. Stock is basically identical. Why does this not change?

 

Answer: my engine's power characteristics. 3500rpm at 75 mph is right where my motor comes on cam and begins making power. This means I do not have to put my foot down to accelerate, I merely need to touch the throttle. At lower rpms, you are burning less in steady state, but are burning far more when you have to floor it to get the car to do anything. American V8s make power far lower down the rpm band than my engine does and are most economical at low rpms; this is a very engine specific thing.

 

Similarly, the claim that all cars are more efficient at 55mph and below is a bunch of bull. As anyone who has actually studied this, or driven more than one car on the highway has discovered, engines have different power delivery characteristics. It is absolutely true that above 60mph, aerodynamic drag becomes important. I am not disputing that. A car is only most efficient at 55mph when the engine is geared to be in its powerband in top gear at that speed. American muscle car? Yes, probably. Friend's 1994 BMW 325i? Hell no. I tested this very theory coming back from the middle of Utah. Constant 55-60 mph, 27-28 mpg. Constant 80-100 mph (Utah is boring as all hell), 30-33 mpg. I averaged 30 mpg at 90mph for three hours straight. It is all about where power is delivered in the rev range, and how efficient the car is both aerodynamically and mechanically.

 

Thats pretty sweet. And very useful information.

 

That sounds like a good deal, and will be especially good if you can do the work it will need yourself. Working on cars builds character!

 

Granted, it's a truck, but if you REALLY want to dissuade passengers from riding with you, and honestly, who wants to have trash, mess, food, and empty drinks from passengers, put harnesses in your car. NOBODY will want to ride with you.

 

Yeah I can do all the work myself. And if I can't my neighbor is a mechanic and has offered to help with anything I need. And he can get me cheap parts.

 

Yeah the only passenger I want is my girlfriend.. And even then.... ya know

 

 

It seems to me that you are looking for a cheaper truck with good mpg's. If I were you, I would buy the best possible truck or car (subaru + trailer is easily cheaper than a $3700 truck) that you can for your budget. There's cheap, fast, and reliable. Pick two. Cheap and Fast isn't Reliable; Reliable and Cheap isn't Fast; Reliable and Fast isn't Cheap.

 

I don't care about fast. I want reliable and cheap. That by far is the hardest combo.

 

 

 

Don't waste your money or time. Seriously.

 

The amount of energy it takes to break the molecular bonds between the hydrogen and oxygen atoms is more than you will get by combusting the fuel. You will end up burning slightly more fuel, if any difference, and making zero impact on your emissions or fuel consumption.

 

I still may try it. I don't really have anything to lose by testing it. And then I can tell people from first hand experience that it dose or doesn't work.

 

Back to the NG issue from your OP-

 

I had a chance to talk with a colleague who has done research into using NG as a vehicle fuel. He did research on converting a diesel engine to use on CNG- compressed natural gas. Aside from the necessary conversions, such as adding spark plugs, changing intake manifold injection, lowering compression, and some other details, he was able to convert a diesel and run quite a few tests on the CNG powered engine.

 

He found that NG is quite suitable for a vehicle, with these key findings:

 

-Engine compression of 12:1 and higher (normal gasoline is 8-10:1)

-Gasoline engine blocks aren't suited to use as CNG, as the fuel burns much, much hotter and is injected at much, much higher pressures. Normal gasoline blocks will crack, fatigue, and break.

-Significantly cleaner emissions

-Significantly reduced usable range. On the order of 1/12th that of gasoline for comparable fuel amounts.

 

Unless the fuel cost is significantly cheaper, and it isn't likely to be if there is a nationwide infrastructure, CNG makes no sense from an economic viewpoint.

 

However, as is the case with Hybrid cars, there are many people who would pay more money for a car with lower emissions. Just like with a Prius, where the additional MPGs will never pay back the higher cost delta over a conventional car unless you drive it for 200k or so, so it would be with a CNG car. The fuel may cost less, but the car will cost more, resulting in a zero-sum game at best. However, you would have the cleanest emissions this side of a hydrogen internal combustion engine.

 

Alright. Well thank you for all the information you have given me. It would be cool to have CNG cars but I guess it just wont happen. Yet at least.

 

because anyone who dares invent such things are taken out by oil company hired assassins wielding electromagnetic beam guns

 

Interesting...... And kinda true..

[Bimmerman]

Bimmerman...you are full of win. That's all I have to say about you.

 

Thanks for the compliment! I'm one of the resident car nuts, and more than happy to answer questions.

 

So far as ethanol: if we continue this way...I can only see that we will be making corn (or whatever it is made from) shorter in supply and more expensive in the near to mid term future. And for what? I have my doubts as to how much effect it will *actually* have on the market.

 

Ethanol.....yea. Ethanol fuels, regardless of E10, E24, E85, all have cleaner NOx, CO2, CO, and etc main emissions than pure gasoline, though not by much. Ethanol fuels, however, have the peculiarity of emitting.....formaldehyde, acetane, methane, and other not really pleasant bits. Ethanol fuel also gets reduced fuel mileage, depending on which grade.

 

E10= normal 'gasoline' in the states. 10% Ethanol. The number is the percentage.

E85 = 'Ethanol' and is 85% ethanol.

 

I have the most experience with E85 and E24, so I'll respond for those. E24 is only available in Brazil, so it's not even that important for Americans.

 

E85 loves to eat through fuel lines. The fueling system on a 'Flex-Fuel' car needs higher grade materials to survive the larger demands placed on it. E85 also has FAR less energy content than gasoline, just about 33% less in fact. While your emissions are lower than they would be for gasoline, your mpgs suffer by almost exactly 33%.

 

Interesting side bit- fuel economy is a function of emissions. the lower your emissions on any type of fuel, the lower your consumption/higher your fuel economy.

 

What the lower energy by mass means for you, the consumer and average car buyer, is that it makes absolutely no sense to use Ethanol fuels unless they are priced at or below the equivalent mileage percentage hit of gasoline. What I mean is say gas sells for $1 per gallon. For E85 to be profitable for you, the consumer, it has to sell for $0.66 a gallon or less. Otherwise, why would you pay more money to drive less distance?

 

Now, as for supply and demand. The majority of current ethanol is not corn based, but rather derived from Brazilian sugar cane. There are a few peculiarities to using that as a fuel source that I am not too fluent on(only aware of), but the whole farmers growing corn for fuel only hasn't happened yet. Ethanol costs a lot to produce and refine in enough quantity for the demand, so without the government subsidies it would sell for around the price of gas if not more. Not exactly great, is it?

 

The sheer irony of using corn as a fuel is that the amount we currently do liquify and burn is enough to feed Africa. True story.

 

So far as natural fuel...isn't mining it also a major concern for all the same reasons that mining pretty much anything else is?

 

Now, the beauty of natural gas is that it does occur naturally. In its purest form, it is nothing more than methane; CH4. It exists in the atmosphere naturally (not all that much tho), and is found in the ground, as well as near oil wells. If you go out to the midwest (east Colorado, Kansas, Nebraska, etc) many of the oil wells you will see are actually natural gas wells. It is a gas above 91 K or -297 degF, and is "mined" the same as oil, with a few differences. I'm not too knowledgeable on that part though.

 

Additionally, it is a byproduct of oil refining, which is where much of the industrial and household natural gas comes from. To get pure enough fuel for cars though, as the cleaner and more pure the gas the better the emissions results, and the refined byproduct needs more refining and processing.

 

It is also what you emit after eating tacos y burritos. Cows produce it too. The UK car show Top Gear did an episode where they converted a car to run on CNG....from cows and from people. Hilarity ensued.

 

Yeah I can do all the work myself. And if I can't my neighbor is a mechanic and has offered to help with anything I need. And he can get me cheap parts.

 

Yeah the only passenger I want is my girlfriend.. And even then.... ya know

 

Kudos! There are too many people now who are inept at even changing the oil on a car. Rebuilding an engine, changing brakes, I can understand, but pointing out a dipstick and changing the oil? Not that hard.

 

I don't care about fast. I want reliable and cheap. That by far is the hardest combo.

I know-- it's just a common saying for racing. You can replace fast with economical, low emissions, sex appeal, comfort, etc. It is a really hard bargain to strike, even if you don't care about speed. Reliable and cheap is hard to come by. Good luck in your quest!

 

Alright. Well thank you for all the information you have given me. It would be cool to have CNG cars but I guess it just wont happen. Yet at least.

 

No problem! I learned a bit too, so I'm glad you asked the question. The buses in my hometown used to run on CNG, and some still do; it's just not too practical for normal drivers currently. That, and the reserves of CNG are much less than that of oil. It's only cheap because it's a byproduct of refining oil and there's much less demand for it.