Car That Can Park Itself Put on Sale by Toyota

It's a toy. It derives its figures not from actual measurements, but from gas mileage and the emission standards complied with.

Reply to
Matthew Russotto
Loading thread data ...

A bike would have kept you through the 'shortage' without causing any pollution.

Mike

Reply to
Mike

Approximately 9/7/03 20:29, C. E. White uttered for posterity:

Yeah, and you could probably tow the Prius around behind it on a trailer [just in case] with no observable affect on the hummer's mileage.

Reply to
Lon Stowell

The quantity of oil, the quality of oil, our need for oil that can be bought and refined before shipping makes the business alliance necessary for the foreseeable future. There is not a shortage of crude oil. There is a refining capacity shortage in the US which is what drives the pump price fluctuations. The "greenies" interference in new refining capacity in the US makes us all the more dependent on finished petroleum product from outside the US.

Reply to
Philip®

I took a look at the Tailpipe Tally website:

formatting link
While the data is "fun", it is limited because it does not reach back far enough. Far enough for my purposes would be 1965 for useful pre-smog comparisons. Also, the 1978 Nova example does not detail the particular car's engine options which spanned from a 250 cu/in inline 6 cylinder thru the venerable 350 cu/in V8. While I am not going to question further the data provided, the obvious advice bias is there for all to see.

Reply to
Philip®

You must be very young and stoopid.

Reply to
Roger Blake

Actually the cabin humidity will probably increase if you habitually use recirculate (compared to using the fresh air setting). When outside air is brought in and cooled it is drier than the average air in the car when it exits the A/C unit. This dry air displaces an equal volume of the more humid air in the cabin. On recirculate you are working across a smaller temperature drop and less moisture is removed per cycle through the evaporator. On recirculate the air exiting the evaporator will be no drier than the outside air that is cooled down when you are in the fresh air setting. Since you are on recirculate, this air does not displace any of the more humid cabin air. Therefore the average humidity goes up, not down when you are on recirculate. Don't forget, you and your passengers are constantly adding water vapor to the air in the cabin. Or another way to think of this - On recirculate the only way moisture is removed is through the evaporator drain pan. When in the fresh air position, you are removing air via the evaporator drain pan and by forcing more humid air out of the cabin by displacing it with dry fresh air.

If you air conditioner is in good condition and you are not in some extraordinarily hot environment, there is rarely any measurable performance advantage to using the recircualte position. In theory you should save a little fuel, but I doubt it is measurable. If you are trying to avoid outside air, then recircualte is useful, otherwise it is just for show.

Ed

Reply to
C. E. White

Not true. I did that experiment. Have the car idling with A/C on RECIRC results in very little ... then ... no condensation dripping on the pavement. But repeat with A/C on FRESH and the puddle of water on the pavement becomes a lake! I hasten to mention I live in southern California about 12 miles inland from the beach.

Disagree, when outside humidity is high. Also, when you first get into a car that has been parked in the sun with the widows rolled up, the interior temperature may be 115 degrees while the outside ambient may only be 85. Greenhouse effect from all the glass surrounding the passenger compartment.

False. On RECIRC, humidity goes DOWN. Evidence is the pool of condensation water dripping on the ground under the vehicle. However, there is a downside limit on the dehumidifying effect. NOTE.... anytime you use the defroster, the A/C is engaged for the express purpose of DEHUMIDIFYING the cabin air.

In FRESH you removing "air?" Ooops! How about water? The notions you have about dehumidification suggest you live in a desert. Is so?

There is evidence that systems operated in RECIRC often experience mold growth on the evaporator. Not good.

RECIRC is suggested in the Owners Manual to prevent dirt from entering the A/C-heater system when on dirt roads. Another time to use RECIRC is when following an obnoxious source of exhaust stench. Otherwise, use FRESH.

Reply to
Philip®

I'm not talking about the recent and inconsequential price fluctuations, but of the current impossibility of meeting our needs from domestic sources. It will be a good thing to stop funnelling money into the hands of fundamentalist fanatics through the hands of Saudi oil ministers. Wider application of existing technology would make that possible.

And give credit where it is due: without the "greenies" we all would have been inhaling lead for the last 30 years.

Reply to
Richard Schumacher

One really has to know the rates to calculate the right answer: the heatload from Sunlight and conduction, the rates at which the occupants expel heat and water, the rates at which they enter through the incoming airstream (if any), and the rate at which the evaporator can remove them.

Agreed that the economy differences are small either way, even though it does get awfully hot and humid in Dallas. And in cool wet weather one has to bring in outside air to keep ahead of the condensation. I prefer recirc when possible just to breathe less of the crap in the air around me on the highway.

Reply to
Richard Schumacher

I was referring to ALL gasoline "crisis" in the past 30 yrs. BTW, the greenies have just as much detriment to their credit when you look at array of activities they are involved in. They look respectable when you ignore a lot of other things.

Reply to
Philip®

You missed the point entirely. Of course when you cool down humid outside air, you remove more water from the air stream than when you cool down lower humidity cool air from the car. However, if your A/C is in good condition, and the outside conditions are not extreme, the air coming out of the evaporator will be basically the same whether you started with outside air or recirculated air from the cabin. The air exiting the evaporator will be 35 to 40 degrees Fahrenheit and around

95% relative humidity no matter which source you started with. When this cool moist air mixes with warmer air from the cabin the humidity drops to a lower level. The water dripping from the car is the water removed from the air feeding the evaporator. When you are in recirculate mode, the air you are running through the A/C does not displace air out of the car (at least not significant amounts). This means that the only way moisture is removed from the car is via condensation in the evaporator. When you bring in outside air, cool it, dehumidify it, and then blow it into the cabin, you are introducing the same temperature and humidity air as when you are in recirculate mode. However, when in the fresh air mode, the air you are introducing displaces an equal volume of cabin air. The air displaced from the car is warmer and moister than the air you are introducing. When it leaves the car, the air takes moisture with it. If the driver and passengers were not continually introducing moisture to the cabin, the recirculate mode would eventually reach equilibrium and the water would stop dripping. However, since people do breath and add moisture to the car, the fresh air mode will result in a lower humidity in most cases. Think about it.

I was mostly talking steady state. However, when you first get in the car, the best way to cool the car down fast is to lower the window and leave the A/C in the fresh air mode. This way you only have to cool down air that started out at the outside temperature, not the hot air from the car. With the windows down, the cooled fresh air will displace the hotter air out the windows.

You are forgetting all the moisture you are adding to the air by breathing and sweating. For the defroster, most cars bring in fresh air to be dehumidified and don't use the recirculate mode when defrosting. I have never disputed that the A/C dehumidifies the air. I am just trying to make sure people understand that the recirculate mode is not as effective at dehumidifying the air as the fresh air mode in most circumstances.

I meant to say "removing water." Sorry for the typo. When in the fresh air mode, you remove water via the drain pan and via displacement of moist air from the cabin. In recirculate mode, you only remove water via the drain pan.

There is evidence that mold grows on the evaporator no matter what mode you operate the A/C in. It is cool, dark, moist area. This is a perfect mold growing environment. Running the climate control system with the compressor off in the fresh air mode for a few minutes before shutting the car down can dry out the evaporator and reduce the chances of mold growth. Some higher end cars now include logic in the climate control system that will run the climate control system fan for a few minutes after the vehicle is shut down to reduce mold growth.

Well, at least I agree with this part.

Regards,

Ed White

Reply to
C. E. White

I disagree. The only thing that stands between the US and independence from Saudi oil is the low price of Saudi Oil. Technologies have exited for years to produce gasoline from oil shale or coal - we have these resources in super abundance. Most US oil fields still contain more than

50% of their original contents. Unfortunately gasoline created from coal and oil shale or from oil recovered from old fields is considerably more expensive than gasoline produced from cheap Saudi Oil. The Saudis know this and manipulate the price to keep alternate sources of gasoline from being developed. If we would elect intelligent representatives that were not addicted to oil company money, then we could institute a reasonable, slowly escalating taxes on imported oil and slowly wean ourselves from imported oil. These taxes would have the side benefit of making vehicles that use lots of fuel less attractive.

Well I am not sure who you ar including as "greenies." There are many reasonable people who have worked to improve the environment and done great things. Then there are the two bit hypocrites like Arianna Huffington who make me want to puke. Maybe we need both to make improvement......I wish this was not true.

Regards,

Ed White

Reply to
C. E. White

IIRC Cleveland is where it is assembled. Don't quote me on that (it somewhere in USA, just haven't been to the dealership recently enough to remember what that tag in the window says word for word).

And no, i do not consider a Canadian engine import. CA and US have a lot of sharing there. The windsor plant has been making engines for a LONG time for Ford (For all ya people out there that don't know, Windsor, Canada is across the way from Detroit. )

Reply to
Bear Trucker Lvr

That would be stupid. Better to use the imported stuff FIRST.

Reply to
Matthew Russotto

I would agree with that, except that the money we pay for the imported stuff is financing a bunch of crazy people and forcing us to spend billion on protecting the imported stuff. Honestly, if Saddam Hussein hadn't had billions of dollars in oil money to spend, would we have cared what he did to his citizens? If Iran didn't have billions to spend, would we be worried about them developing nuclear arms? If North Korea had oil, don't you think George W might have decided they were the most important member of the axis of evil?

Ed

Reply to
C. E. White

Windsor is actually South of Detroit!

Old "auto pact" between Canada and the US said that for every car sold in Canada, one had to be made here. There was a time when this hurt the auto makers a little, because Canadian dollar was higher than US dollar

-- REALLY!, then we were actually more efficient at making cars, even with our higher level of social program costs -- so more vehicles were made in Canada than were sold here. Alas, that is no longer the case and with our dollar climbing higher again, we are less efficient.

Dan

Reply to
Dan Gates

There is no way 95% relative humidity air is exiting the dash registers when ambient outside air is say ... 20%, as is the case in much of my desert driving. It is true that in RECIRC and -starting- with 95% relative humidity inside the car that the passenger compartment humdity will steadily drop. Just look at the puddle under the car, even with nobody inside it.

Are you sure about that wording? Air exiting the evaporator left some of its suspended moisture on the surfaces of the evaporator so ... it is now drier. If one added "cool moist air" to warmer air in the cabin, then the humidity has to .... rise.

In FRESH mode, this is true.

Agreed. In RECIRC, the water dripping is humidity removed from recirculated cabin air

Depends on the humidity level and temperature of ambient air vs. cabin air. If the A/C is fed 110 degree fresh air, the A/C output air will be warmer than when the A/C is fed 75 degree recirculated air (assumes constant fan speed).

We agree on this point.

I have. Unless a person gets into his car wearing very wet clothing, the ambient air (in my case living in a moderately humid place) contributes MUCH more humidity to the passenger compartment than breathing does. MUCH more. The evidence is the greatly increased evaporator sweating using FRESH mode than RECIRC.

The assumption is fresh outside cold air is less humid than recirculating cabin air surrounding a relatively warm, breathing, and sometimes wet occupant. Certainly not always. You have made the case for FRESH being more effective in colder/drier climates but you have not made the case for FRESH being more effective than RECIRC for dehumidification in climates known for very high humidity. As anyone in the deep southern states knows, there is no amount of heavy breathing inside a car than can match the ambient summer humidity. In places where evaporator icing results from too much condensation on a properly operating A/C, the immediate solution (after thawing) is to run the A/C in RECIRC in an effort to reduce evaporator sweating (which turns to ice in extreme cases).

I have found mold complaints more prevalent in cars where people use RECIRC only, their thinking being RECIRC meant colder output.

Reply to
Philip®

Nor would I. Canada is pretty much U.S. Lite(tm).

I never had a problem with NAFTA opening up Canada. Mexico, though, was the problem. No environmental controls, poor wages and standard of living, and hopelessly corrupt government. Canada is well run, educated, and pays its people decent wages. It's a great place to manufacture things as the taxes and red tape are just so much less than across the border in Detroit or New York.

But guess where most GMs and VWs and... Yep. Mexico. And the quality shows.

Reply to
Joseph Oberlander

Looking at my psychometric chart, 110F air at 20% RH, when cooled to 70F will be at about 75% RH. If the exit air is at 60F, the RH is around

95%. As you state later in this pogo, this assumes no dehumidification, which is not the case (hence the pool of water and the comments "Hey lady, your car is leaking something. You should call a towtruck!"

Let us define terms here, relative humidity, which is quoted by the weather people, is a measure of how much moisture IS in air of a certain temperature, RELATIVE to how much it CAN hold. When air with a constant moisture level gets warmer, the RH goes down! Total moisture stays the same, but that is not what most people refer to when they talk about humidity. When air cools, the RH goes up, hence dew on the grass in the morning. So, when you talk humidity (as the world refers to it) when the "cool moist air" warms, the humidity has to . . . lower

Reply to
Dan Gates

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.