E85 vs Gasoline - credible numbers?

"Joe Fischer" wrote in message

On Sat, 09 Sep 2006 20:49:47 GMT, "Vaughn Simon" vaughnsimonHATESSPAM@att.FAKE.net> wrote: There should be no mystery, it may be that more power means less miles per gallon, but with more power, and an objective of miles per gallon instead of sprint and speed ability, a vehicle should be able to have a different gear ratio.

You are correct, there is no mystery. An ICE is a heat engine. It runs on BTU's. A fuel with fewer BTU's per gallon will yield fewer miles per gallon.
Vaughn

"Joe Fischer" wrote in message

On Sat, 09 Sep 2006 20:49:47 GMT, "Vaughn Simon" vaughnsimonHATESSPAM@att.FAKE.net> wrote:
"Joe Fischer" wrote in message On 6 Sep 2006 17:20:14 -0700, "Mad Scientist Jr" It isn't that simple, there can be more power from ethanol than from gasoline, only the engine needs to be timed different and other changes made.
You have said this before, and I am still not convinced.
I clearly stated before that the article on the switch talked about more power in ethanol, I may have assumed that ethanol and methanol are about the same and that both have more power than gasoline (not more energy per gallon).
If so, this is a bit of science that Detroit had not yet been able to make work. Please read this month's Consumer Reports for some real-world E-85 gas mileage numbers. (HINT: they are dismal)
It might make more sense to sell fuels by the pound or by the BTU, but liquid measure is easier.
I think it is great that at least some vehicles are built to use either ethanol or gasoline, and eventually all could easily be.
If gasoline is in short supply in the future (which could be tomorrow), being able to run any percentage of ethanol would be helpful.
Yes, you can certainly optomize an ICE for ethanol, but there are simply fewer BTU'u in ethanol than in gasoline and there is no engineering that is going to magically change that. Vaughn
Then I would like to know why the article talked of more power from ethanol over gasoline or ethanol over methanol. While I read the statements about the original switch to methanol being made for safety reasons, I have to wonder if the race committee would chose a fuel with substantially less power, so there may be something about the fuel as it gets into the cylinder and expands the gases and increases pressures that gives it more power, even though the average vehicle gets less miles per gallon.
Perhaps the fact that the jets have to be enlarged to run ethanol in a carburetor means that for the same amount of air, ethanol has more power, and since more is needed, it gets less mileage.
There should be no mystery, it may be that more power means less miles per gallon, but with more power, and an objective of miles per gallon instead of sprint and speed ability, a vehicle should be able to have a different gear ratio.
Maybe they should let the mechanics write the article and say what they mean.
Joe Fischer
If a smaller displacement engine with turbo, direct injection and

other features running ethanol were compared to a larger displacement engine without those features running gasoline, the miles per gallon would depend on the efficiency. (all else being equal..the same kind car and same weight, etc.) If they both produced the same power, the smaller engine would have to be more efficient to make up for the fewer BTUs per gallon in ethanol. Obviously, those efficiency improving features could be added to the larger displacement engine and on and on. The ICE is a heat engine that requires BTUs and no comparison of "apples and oranges" will change the physics of the situation. So, what the discussion seems to come down to is E100 has higher octane than 87 octane gasoline. You can provide turbo boost to get more power out of less displacement with higher octane. But unless the E100 engine is substantially more efficient than its gasoline counter part, the E100 car will get less miles per gallon than the same car using gasoline.

The Ghost In The Machine wrote:

In sci.environment, Steve no@spam.thanks wrote on Sat, 09 Sep 2006 10:19:46 -0500 XICdnTF5atMORp_YnZ2dnUVZ_t6dnZ2d@texas.net>:
Lloyd Parker wrote:
Just the heat generated by turning the knob can set it off and cause a fire/explosion.

But not O2 at 1 atm. Otherwise nobody could breathe it without combustion.
Nobody DOES breathe PURE 02 at 1 atmosphere. Even wearing an O2 mask, there is dilution with nitrogen (primarily) and all the other gasses that make up the soup we call "air."
Pedant point: there was or is the concept of an oxygen tent for seriously ill folks. (Such are presumably rather dangerous because of the problem of increased flammability of burnable materials therein. Apollo 1 was a very sad demonstration thereof.)

I've heard of "hyperbaric oxygen treatment" a number of times, but I'll confess I never really read up on it. I *presume* (dangerous, I know) that its done with either air or mildly oxygen-rich air in a pressure chamber. Before the little over-the-ears and up-the-nose O2 tubes were developed, patients needing oxygen were put under a plastic "oxygen tent" but flammability was definitely a concern with that large a volume of oxygen-rich air. IIRC, getting the O2 concentration too high actually damages lung tissue. Well, again partial knowledge is dangerous- is it oxygen concentration or oxygen partial-pressure that really matters? >

On Sat, 09 Sep 2006 22:09:58 GMT, "Vaughn Simon" wrote:

You are correct, there is no mystery. An ICE is a heat engine. It runs on BTU's. A fuel with fewer BTU's per gallon will yield fewer miles per gallon.

http://news.com.com/2100-11389_3-6075058.html
Good enough for me.
Joe Fischer

Ron Shepard wrote:

In article , Steve wrote:
You do know that Parker is a chemist, right? I've certainly had my disagreements with him, but he IS a chemist.
There is a Loyd Parker who is a chemist at Emory, http://www.oxford.emory.edu/Directories/index.cfm?FuseAction=View&Thi sUserID=130. His email address is parker@learnlink.emory.edu.

I've crossed keyboards with Lloyd for years. I hadn't seen a post from him in the last couple of years because he no longer seems to hang out (and tolerate the continual corrections he received) in rec.autos.tech or rec.autos.makers.chrysler

However, the person posting in these ethanol threads is lparker@emory.edu. It is unlikely that these are the same person.

Oh, I don't know, I think it may be the same Lloyd Parker. But I do know that L1oyd Parker is someone else (pick a different font if its not obvious...) :-)

Evidence for this is that the latter poster has made several simple conceptual mistakes in his arguments, confusing "energy" and "power" for example, and apparently not knowing what is "carnot cycle" efficiency in a heat engine.

Yeah, that's the same old Parker for sure. I never said he was a physicist. Or an engineer. :-)

"Joe Fischer" wrote in message

On Sat, 09 Sep 2006 22:09:58 GMT, "Vaughn Simon" vaughnsimonHATESSPAM@att.FAKE.net> wrote:
You are correct, there is no mystery. An ICE is a heat engine. It runs on BTU's. A fuel with fewer BTU's per gallon will yield fewer miles per gallon.
http://news.com.com/2100-11389_3-6075058.html
Good enough for me.

"While the car did not break last year's record of 9,023 mpg, it was significant in that it was an ethanol-powered vehicle. "
Good enough for me.
Vaughn

aarcuda69062 wrote:

In article , "daestrom" wrote:
In many cars, the oil-pressure sensor is used to enable the electric fuel pump, if it fails you get nowhere.
daestrom
Which? Not GM, Ford, Chrysler, Toyota, Nissan.

GM and Ford both use oil pressure to turn on the pump. The computer only turns on the pump for 30 seconds or so. The oil pressure switch takes over if you have pressure. That is why a vehicle with a failed pump relay takes a bunch of cranking to get it to start, Oil pressure has to come up to turn on the pump.
-- Steve W. Near Cooperstown, New York
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =----

"Steve W." wrote in message

aarcuda69062 wrote: In article , "daestrom" wrote:
In many cars, the oil-pressure sensor is used to enable the electric fuel pump, if it fails you get nowhere.
daestrom
Which? Not GM, Ford, Chrysler, Toyota, Nissan.
GM and Ford both use oil pressure to turn on the pump. The computer only turns on the pump for 30 seconds or so. The oil pressure switch takes over if you have pressure. That is why a vehicle with a failed pump relay takes a bunch of cranking to get it to start, Oil pressure has to come up to turn on the pump.
-- Steve W. Near Cooperstown, New York

You are wrong on both counts. For a long time GM has used a secondary circuit through the oil pressure switch, but Fords have never used the oil pressure switch for anything to do with the fuel pump. Bob

"Bob" wrote in news:UOLMg.779$no3.485@newsfe03.lga:

"Steve W." wrote in message aarcuda69062 wrote: In article , "daestrom" wrote:
In many cars, the oil-pressure sensor is used to enable the electric fuel pump, if it fails you get nowhere.
daestrom
Which? Not GM, Ford, Chrysler, Toyota, Nissan.
GM and Ford both use oil pressure to turn on the pump. The computer only turns on the pump for 30 seconds or so. The oil pressure switch takes over if you have pressure. That is why a vehicle with a failed pump relay takes a bunch of cranking to get it to start, Oil pressure has to come up to turn on the pump.
-- Steve W. Near Cooperstown, New York
You are wrong on both counts. For a long time GM has used a secondary circuit through the oil pressure switch, but Fords have never used the oil pressure switch for anything to do with the fuel pump. Bob

What difference does it make. They are both on the rocks and destined to have Toyota walk on their faces. Their both dead. Get it?

In article , "Steve W." wrote:

aarcuda69062 wrote: In article , "daestrom" wrote:
In many cars, the oil-pressure sensor is used to enable the electric fuel pump, if it fails you get nowhere.
daestrom
Which? Not GM, Ford, Chrysler, Toyota, Nissan.
GM and Ford both use oil pressure to turn on the pump.

GM uses a relay in parallel with an oil pressure switch, Ford relies on CKP signal to keep the fuel pump relay energized, Ford typically doesn't use an oil pressure switch in their fuel pump circuitry.

The computer only turns on the pump for 30 seconds or so.

Initial prime is more like 2-3 seconds, until the PCM sees a signal from the appropriate ignition sensor.

The oil pressure switch takes over if you have pressure.

Nope, on GMs it is in parallel with the fuel pump relay, but the PCM keeps the relay energized as long as there is a CKP signal. IOWs, they all rely on an ignition sensor signal, with the exception of GM who chose to use the oil switch for redundancy.
.. That is why a vehicle with a failed pump

relay takes a bunch of cranking to get it to start,

That's why a -GM product- with a failed fuel pump relay takes a bunch of cranking to get it to start.

Oil pressure has to come up to turn on the pump.

A Chrysler or a Ford with a failed fuel pump relay (*or related circuitry/relay) isn't going to start, no way, no how.
* includes ASD relay

In article , "Sponsored by OILY INC. Exxon-Koch" wrote:

"Bob" wrote in news:UOLMg.779$no3.485@newsfe03.lga:
"Steve W." wrote in message aarcuda69062 wrote: In article , "daestrom" wrote:
In many cars, the oil-pressure sensor is used to enable the electric fuel pump, if it fails you get nowhere.
daestrom
Which? Not GM, Ford, Chrysler, Toyota, Nissan.
GM and Ford both use oil pressure to turn on the pump. The computer only turns on the pump for 30 seconds or so. The oil pressure switch takes over if you have pressure. That is why a vehicle with a failed pump relay takes a bunch of cranking to get it to start, Oil pressure has to come up to turn on the pump.
-- Steve W. Near Cooperstown, New York
You are wrong on both counts. For a long time GM has used a secondary circuit through the oil pressure switch, but Fords have never used the oil pressure switch for anything to do with the fuel pump. Bob
What difference does it make.

The "difference" is, Steve W posted inaccurate information.

They are both on the rocks and destined to have Toyota walk on their faces.

What difference does -that- make?

Their both dead. Get it?

'they're' (contraction for they are)

aarcuda69062 wrote in news:nonelson-2AA923.22584209092006@newsclstr02.news.prodigy.com:

In article Xns9839D382CAB7Acladiusdenksbcglobal@207.115.17.102>, "Sponsored by OILY INC. Exxon-Koch" Exxon_Serial_Murderers@RacketeersR.US> wrote:
"Bob" wrote in news:UOLMg.779$no3.485@newsfe03.lga:
"Steve W." wrote in message aarcuda69062 wrote: In article , "daestrom" wrote:
In many cars, the oil-pressure sensor is used to enable the electric fuel pump, if it fails you get nowhere.
daestrom
Which? Not GM, Ford, Chrysler, Toyota, Nissan.
GM and Ford both use oil pressure to turn on the pump. The computer only turns on the pump for 30 seconds or so. The oil pressure switch takes over if you have pressure. That is why a vehicle with a failed pump relay takes a bunch of cranking to get it to start, Oil pressure has to come up to turn on the pump.
-- Steve W. Near Cooperstown, New York
You are wrong on both counts. For a long time GM has used a secondary circuit through the oil pressure switch, but Fords have never used the oil pressure switch for anything to do with the fuel pump. Bob
What difference does it make.
The "difference" is, Steve W posted inaccurate information.
They are both on the rocks and destined to have Toyota walk on their faces.
What difference does -that- make?
Their both dead. Get it?
'they're' (contraction for they are)

Rhat's why they are dead. They knew everything about 20th century autos that had fuel pumps and nothing about 21st century transportation. They knew the difference between Their and they're but not the difference between 281 ppmv CO2 and 381 ppmv CO2. They knew more about killing off auto unions then they did about putting people behind the wheels of cars you can live with and blue collar people can afford to buy.

In article , "Sponsored by OILY INC. Exxon-Koch" wrote:

Rhat's why they are dead. They knew everything about 20th century autos that had fuel pumps and nothing about 21st century transportation. They knew the difference between Their and they're but not the difference between 281 ppmv CO2 and 381 ppmv CO2. They knew more about killing off auto unions then they did about putting people behind the wheels of cars you can live with and blue collar people can afford to buy.

Toyotas have fuel pumps.

"Vaughn Simon" wrote in message

"Joe Fischer" wrote in message On Sat, 09 Sep 2006 20:49:47 GMT, "Vaughn Simon" vaughnsimonHATESSPAM@att.FAKE.net> wrote: There should be no mystery, it may be that more power means less miles per gallon, but with more power, and an objective of miles per gallon instead of sprint and speed ability, a vehicle should be able to have a different gear ratio.
You are correct, there is no mystery. An ICE is a heat engine. It runs on BTU's. A fuel with fewer BTU's per gallon will yield fewer miles per gallon.

Well, as my grandpa used to say to me, "'taint necessarily so."
Mileage is simply....
<energy per gallon> * <overall efficiency> -------------------------------------------- = miles per gallon <energy required per mile>
There are three terms in that, and you're concentrating on one of them. If the efficiency of the heat engine can be increased because of the type of fuel used, then mileage *could* be the same or better with a different fuel.
The fact that one needs 'bigger jets' for ethanol tells me something without resorting to chemistry textbooks. That the stoichometric ratio for air:ethanol is a lot lower than air:gasoline. Thermodynamically, that can have an interesting affect on flame temperature. As you probably know, the efficiency of a heat engine is affected by the temperatures reached by the working fluid. The temperature reached by an air-fuel mixture is limited by the reaction energy and the specific heat of the mixture. So even though ethanol has less energy per gallon, it may still have a higher flame temperature than gasoline. And that *could* result in higher engine efficiencies.
Of course, a conventional automobile is all 'tweaked out' and tuned based on gasoline. The various gear ratio's, the engine size versus automobile power needs, etc... So just changing out carburation (either jets, or computer module) is not going to use ethanol to its full advantage.
daestrom

"The Ghost In The Machine" wrote in message

In sci.environment, Steve no@spam.thanks wrote on Sat, 09 Sep 2006 10:19:46 -0500 XICdnTF5atMORp_YnZ2dnUVZ_t6dnZ2d@texas.net>: Lloyd Parker wrote:
Just the heat generated by turning the knob can set it off and cause a fire/explosion.

But not O2 at 1 atm. Otherwise nobody could breathe it without combustion.
Nobody DOES breathe PURE 02 at 1 atmosphere. Even wearing an O2 mask, there is dilution with nitrogen (primarily) and all the other gasses that make up the soup we call "air."
Pedant point: there was or is the concept of an oxygen tent for seriously ill folks. (Such are presumably rather dangerous because of the problem of increased flammability of burnable materials therein. Apollo 1 was a very sad demonstration thereof.)
Wiki gives Earth's oxygen percentage as 20.94%. I don't know if that's by weight or by molecular count, but that gives an approximate partial pressure of about 21220 Pascal.

That percentage is 'by volume'. Which works out to be the same as 'molecular count' for ideal gasses (and air's constiuents can be approximated by ideal gasses near STP).
Apollo tragedy happened while the capsule was pressurized *above* atmospheric pressure. Since the capsule was designed for about 4 psia in orbit, it was pressurized to about 4 psi *above* atmospheric pressure during the test. With pure O2, that works out to a partial pressure of about 128 kPa, six times the normal partial pressure of O2. A very dangerous situation.
An interesting side note: Navy divers have experimented with various 'rebreathers' and other devices. One feeds almost pure O2 to the diver and removes the CO2. While useful in some respects (no bubbles are emitted from the system), it has a serious drawback. Pure O2 can be toxic if the partial pressure rises too high, so the operating depth is limited. IIRC, these can't be used below about 20 ft, and are limited in time of use as well as depth. But pure O2 at normal atmospheric pressure is not deadly (except for the increased fire hazard).
http://en.wikipedia.org/wiki/Oxygen_toxicity
daestrom