In general, manuals should have better mileage than automatics, from 1 to 4 mpg more, typically in both city and highway driving. More in city driving though. The more a car has to shift gears, the worse the mileage, because automatic transmissions use more gas in shifting gears.
If this is the case, then the manual would be worse, since they typically have more gears (5 or 6 vs. 4 or 5).
Quote:
The reason the Civic has the same mileage for automatics and manuals is that it has an excellent automatic transmission. The same can't be said for a lot of American vehicles, or even Honda's other vehicles. Manual transmission for mid-size and full sized American sedans and SUVs are a rarity.
I would agree. Also, an automatic transmission is inherently less efficient than a manual one (torque converter, etc. in there).
Quote:
Eventually, continuous variable transmission, or a variation of the theme, will enter the American car vernacular. This transmission is about as efficient as a manual. It's in several cars today. The Saturn Ion VUE and the Honda Civic HX are a couple.
Subaru introduced one in a production car (Justy?) back in 1991 or '92, which nobody bought. Typically they're limited to small cars because the CVT can't handle the torque. However, Audi has introduced it in their A6. That's a good sign.
But we're forgetting the true purpose of an automatic transmission— smoky burnouts at the local 7-11.
One thing I would like to see explored is the possible use of gas turbine engines. They are used in most helicopters because of their awesome power to weight ratio and are smaller than their internal combustion counterparts. They also have flexable fuel requirements. It can use kerosene, natural gas, rocket fuel, gasoline, etc.
Problem is that they are expensive to manufacture because of the high speed and friction they make you need some expensive materials to make them. But this can be overcome with exotic high temp ceramics and other heat resistant materials. Another disadvantage I can see is that gas turbines like a constant flow of fuel so the load is now constant and not fluctuating like in an IC engine that powers the drivetrain directly. But this is also a disadvantage for an IC engine because a fluctuating load is less fuel efficient. So turn that frown upside down, so to speak. make that disadvantage an ADVANTAGE. How? by using it as a generator and not a direct method of propulsion. So you would still need an electric motor for main power but the gas turbine would be a more efficient way to make electricity. We already do that. Some powerplants use gas turbines for electricity production and others use steam turbines (coal, natural gas, oil, etc.).
Imagine a 180hp electric car with 220lb/ft torque that gets 100mpg! And this may be a conservative estimate.
If this is the case, then the manual would be worse, since they typically have more gears (5 or 6 vs. 4 or 5).
I'm mostly talking about how automatic transmissions take such a long time changing gears here. My Sport Trac is pretty hitchy at around 50 to 60 mph. It doesn't seem to know what gear it wants to be in, and gets stuck waiting for me to stomp on the gas.
I also wonder how much gas is wasted while an engine is at idle for a manual (car at rest) compared to an automatic in 1st gear with foot on the brake (car at rest)...
Quote:
Subaru introduced one in a production car (Justy?) back in 1991 or '92, which nobody bought. Typically they're limited to small cars because the CVT can't handle the torque. However, Audi has introduced it in their A6. That's a good sign.
I remember that. [sarcasm]Audi and Subaru. Wow, more non-American automakers producing more efficient engines.[/sarcasm]
Yeah but those cars used the turbines to power the drive-train. I would like to see if it would be cost effective for it to be used as a generator.
I don't see why not. You already have electric cars that run off of batteries, put the turbine in as a generator and you have tons of power and torque as electric cars have that and then some. What they do not have is long battery life. I would buy one...If it came in minivan size. Family and all...
from everything i've ever read on the subject, flywheels are the ONLY realistic possibility at this point in time for having a car with great fuel effeciency and still has acceleration when needed. in this case we're talking something that would get close to 80-150 mpg. although it looks like they're making progress with hybrids.
i think the problem with flywheels was that you get something that dense spinning that fast and you're talking some serious damage if it flys off.
Thermodynamically speaking, the engine is more efficient in summer, because the difference between the intake air and exhaust gas is smaller. However, it should be more powerful in winter, when it can pack more cold, dense air in the cylinders.
Ford has an intercooler design using the air conditioner to add about 10% more horsepower in their engines with superchargers for about 2 minutes.
I think the loss of efficiency Scott is seeing, I'm assuming his driving habits, is the result of warming up the car (if it is 10 deg F), slippery driving conditions, and the "tightness" of the engine becoming worse when it becomes really cold. Ie, lubricants don't work as well, fuel mixing not as good, etc.
from everything i've ever read on the subject, flywheels are the ONLY realistic possibility at this point in time for having a car with great fuel effeciency and still has acceleration when needed. in this case we're talking something that would get close to 80-150 mpg. although it looks like they're making progress with hybrids.
Ultracapacitors can get both the fuel efficiency and the acceleration.
Re pods - yeah, something like that would be nice. A lot of people really don't like rubbing shoulders on buses and subways, but the current automobile model is just not sustainable in the long run. Your idea might also deal - partly - with the difficulty in providing public transit to sprawling suburbs.
Comments
Originally posted by THT
In general, manuals should have better mileage than automatics, from 1 to 4 mpg more, typically in both city and highway driving. More in city driving though. The more a car has to shift gears, the worse the mileage, because automatic transmissions use more gas in shifting gears.
If this is the case, then the manual would be worse, since they typically have more gears (5 or 6 vs. 4 or 5).
The reason the Civic has the same mileage for automatics and manuals is that it has an excellent automatic transmission. The same can't be said for a lot of American vehicles, or even Honda's other vehicles. Manual transmission for mid-size and full sized American sedans and SUVs are a rarity.
I would agree. Also, an automatic transmission is inherently less efficient than a manual one (torque converter, etc. in there).
Eventually, continuous variable transmission, or a variation of the theme, will enter the American car vernacular. This transmission is about as efficient as a manual. It's in several cars today. The Saturn Ion VUE and the Honda Civic HX are a couple.
Subaru introduced one in a production car (Justy?) back in 1991 or '92, which nobody bought. Typically they're limited to small cars because the CVT can't handle the torque. However, Audi has introduced it in their A6. That's a good sign.
But we're forgetting the true purpose of an automatic transmission— smoky burnouts at the local 7-11.
Originally posted by Outsider
One thing I would like to see explored is the possible use of gas turbine engines. They are used in most helicopters because of their awesome power to weight ratio and are smaller than their internal combustion counterparts. They also have flexable fuel requirements. It can use kerosene, natural gas, rocket fuel, gasoline, etc.
Problem is that they are expensive to manufacture because of the high speed and friction they make you need some expensive materials to make them. But this can be overcome with exotic high temp ceramics and other heat resistant materials. Another disadvantage I can see is that gas turbines like a constant flow of fuel so the load is now constant and not fluctuating like in an IC engine that powers the drivetrain directly. But this is also a disadvantage for an IC engine because a fluctuating load is less fuel efficient. So turn that frown upside down, so to speak. make that disadvantage an ADVANTAGE. How? by using it as a generator and not a direct method of propulsion. So you would still need an electric motor for main power but the gas turbine would be a more efficient way to make electricity. We already do that. Some powerplants use gas turbines for electricity production and others use steam turbines (coal, natural gas, oil, etc.).
Imagine a 180hp electric car with 220lb/ft torque that gets 100mpg! And this may be a conservative estimate.
Like this? http://www.turbinecar.com/turbine.htm
Back to the future, but will people bite?
Originally posted by NoahJ
Like this? http://www.turbinecar.com/turbine.htm
Back to the future, but will people bite?
Yeah but those cars used the turbines to power the drive-train. I would like to see if it would be cost effective for it to be used as a generator.
Originally posted by GardenOfEarthlyDelights
If this is the case, then the manual would be worse, since they typically have more gears (5 or 6 vs. 4 or 5).
I'm mostly talking about how automatic transmissions take such a long time changing gears here. My Sport Trac is pretty hitchy at around 50 to 60 mph. It doesn't seem to know what gear it wants to be in, and gets stuck waiting for me to stomp on the gas.
I also wonder how much gas is wasted while an engine is at idle for a manual (car at rest) compared to an automatic in 1st gear with foot on the brake (car at rest)...
Subaru introduced one in a production car (Justy?) back in 1991 or '92, which nobody bought. Typically they're limited to small cars because the CVT can't handle the torque. However, Audi has introduced it in their A6. That's a good sign.
I remember that. [sarcasm]Audi and Subaru. Wow, more non-American automakers producing more efficient engines.[/sarcasm]
Originally posted by Outsider
Yeah but those cars used the turbines to power the drive-train. I would like to see if it would be cost effective for it to be used as a generator.
I don't see why not. You already have electric cars that run off of batteries, put the turbine in as a generator and you have tons of power and torque as electric cars have that and then some. What they do not have is long battery life. I would buy one...If it came in minivan size. Family and all...
i think the problem with flywheels was that you get something that dense spinning that fast and you're talking some serious damage if it flys off.
now this on the other hand looks sweet.
http://www.springfieldnews-leader.co...key120402.html
Originally posted by GardenOfEarthlyDelights
Thermodynamically speaking, the engine is more efficient in summer, because the difference between the intake air and exhaust gas is smaller. However, it should be more powerful in winter, when it can pack more cold, dense air in the cylinders.
Ford has an intercooler design using the air conditioner to add about 10% more horsepower in their engines with superchargers for about 2 minutes.
I think the loss of efficiency Scott is seeing, I'm assuming his driving habits, is the result of warming up the car (if it is 10 deg F), slippery driving conditions, and the "tightness" of the engine becoming worse when it becomes really cold. Ie, lubricants don't work as well, fuel mixing not as good, etc.
Originally posted by alcimedes
from everything i've ever read on the subject, flywheels are the ONLY realistic possibility at this point in time for having a car with great fuel effeciency and still has acceleration when needed. in this case we're talking something that would get close to 80-150 mpg. although it looks like they're making progress with hybrids.
Ultracapacitors can get both the fuel efficiency and the acceleration.
Originally posted by Outsider
What do yall think of my utopian idea?
Re pods - yeah, something like that would be nice. A lot of people really don't like rubbing shoulders on buses and subways, but the current automobile model is just not sustainable in the long run. Your idea might also deal - partly - with the difficulty in providing public transit to sprawling suburbs.
Utopian though.