Alcohol as a fuel

Ulf > wrote in
:

> Daniel J. Stern wrote:
>> On Fri, 13 May 2005, Nate Nagel wrote:
>>
>>
>>>>>if you add back the proper amount of fuel then no power loss is
>>>>>realized
>>
>>
>>>>...which, of course, explains why FFVs are so much doggier when
>>>>driven on M85 than on gasoline.
>>
>>
>>>They really shouldn't be
>>
>>
>> And yet...!
>
> "On the road, the 180 bhp/ 280 Nm Saab 9-5 BioPower running on E85
> delivers sportier performance due to a significant 30 bhp lift in
> maximum power and 40 Nm more torque, compared to its gasoline-powered
> equivalent. Whilst fuel economy in SEK/km in city and mixed driving
> conditions is unlikely to show an improvement, testing indicates that
> a useful 15 per cent gain in fuel cost in SEK/km can be expected at
> cruising speeds because of a better combustion with higher
> efficiency."
>
> http://saab.com/main/GLOBAL/en/press...nt/2/index.xml
>

thats what can happen when the eng is built for high ethanol content. the
comp. automaticly raises the boost if ethanol is used instead of gas.
probly uses a higher comp ratio to start also. KB

--
ThunderSnake #9 Warn once, shoot twice
460 in the pkup, 460 on the stand for another pkup
and one in the shed for a fun project to yet be decided on

In article >, Steve wrote:
> Maybe its not what you intended, but from my chair that's exactly what
> you did.

Other people got it just fine.

> I pointed out that high(er) compression combustion is a more
> thermally efficient process by a great enough degree to offset the
> difference in energy content in the fuel required. Then you brought up
> HiPo 60s v8s, which have nothing to do with the basic question.

Look, I brought 87 vs 92 octane as an example of theme. If you want to
play usenet hair splitting fine. go for it, I don't give a ****, I'm too
old for it.

Brent P wrote:


>
>>I pointed out that high(er) compression combustion is a more
>>thermally efficient process by a great enough degree to offset the
>>difference in energy content in the fuel required. Then you brought up
>>HiPo 60s v8s, which have nothing to do with the basic question.
>
>
> Look, I brought 87 vs 92 octane as an example of theme.

A "theme?" What "theme?" Floral or earth-tones?


If you want to
> play usenet hair splitting fine. go for it, I don't give a ****, I'm too
> old for it.

So am I, and that's not what I'm doing. I was pointing out what I
perceived as an utterly incorrect generalization, not bring up totally
irrelevant pseudo-comparisons of engines separated by 40 years in time
and 200 horsepower in output.

I'll admit that its possible that I'm old and senile enough to have
completely missed the point. But I don't think so....

Steve wrote:
> Nate Nagel wrote:
>
> >
> > I would suggest that the poor fuel economy might have been caused
by a)
> > cam timing that makes the idle sound like the drum intro of "Hot
For
> > Teacher" b) running the engine waaaay outside the sweet spot on the
BSFC
> > curve (due to a) that's going to be at a fairly high RPM)
>
>
> No, they're not efficient, but DAMN they sure are a lot of fun!!!

No argument there! Nothing says "fun" like sitting at a stoplight and
watching your whole front end sheetmetal dance around
(anticipation...)

nate

N8N wrote:

> Steve wrote:
>
>>Nate Nagel wrote:
>>
>>
>>>I would suggest that the poor fuel economy might have been caused
>
> by a)
>
>>>cam timing that makes the idle sound like the drum intro of "Hot
>
> For
>
>>>Teacher" b) running the engine waaaay outside the sweet spot on the
>
> BSFC
>
>>>curve (due to a) that's going to be at a fairly high RPM)
>>
>>
>>No, they're not efficient, but DAMN they sure are a lot of fun!!!
>
>
> No argument there! Nothing says "fun" like sitting at a stoplight and
> watching your whole front end sheetmetal dance around

Or driving through a parking garage setting off all the car alarms as
you idle past by with the top down and the A/C blowing... :-)

In article >,
Nate Nagel > wrote:
>Daniel J. Stern wrote:
>
>> On Fri, 13 May 2005, Kevin Bottorff wrote:
>>
>>
>>>if you add back the proper amount of fuel then no power loss is realized
>>
>>
>> ...which, of course, explains why FFVs are so much doggier when driven on
>> M85 than on gasoline.
>
>They really shouldn't be, ASSuming they have big enough injectors. MPG
>would be in the toilet of course.

Well, if you've optimized everything -- fuel pressure, injector pulse
width, injector size -- for gasoline, you can't also optimize the same
for E85. All you can easily change is the pulse width.
--
There's no such thing as a free lunch, but certain accounting practices can
result in a fully-depreciated one.

Don Stauffer wrote:
>
> Jasper Janssen wrote:
> > On Sat, 07 May 2005 09:09:29 -0500, Don Stauffer >
> > wrote:
> >
> >
> >>However, I agree that the loss of hp in the 30 - 50% range is fiction.
> >
> >
> > He didn't say loss of HP, he said loss of mileage. If I read the tables
> > correctly, a gallon of alcohol contains less stored energy than gasoline,
> > so that's the right way to bet.
> >
> >
> >> Without raising the CR of the engine, one does loose a little hp. How
> >>much depends on whether engine has a knock sensor that will advance
> >>spark a bit on higher octane fuels.
> >
> >
> > Knock sensors never advance spark timing for higher octane fuels; all they
> > do is retard the timing if the octane is too low to support the CR. Since
> > that's never more efficient with a given fuel than just having the right
> > CR and the right timing, you don't *want* the knock sensor to be used in
> > that way.
> >
> > Jasper
>
> You're right- he did say milage, the hp in my statement was a goof.
> However, the amount of energy loss in a 15% mixture would create a 7.5%
> loss of milage, not 30-50%.
>
> And if the spark is retarded LESS on one fuel than another, then it is
> relatively ADVANCED compared to the second. Less retard is a relative
> advance.

It comes down to derivability with the alcohol mixes. My engine has no
computer controls and no knock sensor and has a carb. The timing
advance is ported.

When I run 91 octane gasoline, I only need the gas pedal to the floor on
big hills, it will hold a nice 70-75 mph on the flats with about a half
pedal.

When the alcohol is added, it will only go over 65-70 mph on a down hill
and to hold that 65 it needs to be right to the floor on the flats and
geared down to 3rd on the hills. It sputters at idle too.

I wasn't making the mileage numbers up, I drive by miles per tank
because the gauge only sort of works.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Mike Romain > wrote in
:

> Don Stauffer wrote:
>>
>> Jasper Janssen wrote:
>> > On Sat, 07 May 2005 09:09:29 -0500, Don Stauffer
>> > > wrote:
>> >
>> >
>> >>However, I agree that the loss of hp in the 30 - 50% range is
>> >>fiction.
>> >
>> >
>> > He didn't say loss of HP, he said loss of mileage. If I read the
>> > tables correctly, a gallon of alcohol contains less stored energy
>> > than gasoline, so that's the right way to bet.
>> >
>> >
>> >> Without raising the CR of the engine, one does loose a little hp.
>> >> How
>> >>much depends on whether engine has a knock sensor that will advance
>> >>spark a bit on higher octane fuels.
>> >
>> >
>> > Knock sensors never advance spark timing for higher octane fuels;
>> > all they do is retard the timing if the octane is too low to
>> > support the CR. Since that's never more efficient with a given fuel
>> > than just having the right CR and the right timing, you don't
>> > *want* the knock sensor to be used in that way.
>> >
>> > Jasper
>>
>> You're right- he did say milage, the hp in my statement was a goof.
>> However, the amount of energy loss in a 15% mixture would create a
>> 7.5% loss of milage, not 30-50%.
>>
>> And if the spark is retarded LESS on one fuel than another, then it
>> is relatively ADVANCED compared to the second. Less retard is a
>> relative advance.
>
> It comes down to derivability with the alcohol mixes. My engine has
> no computer controls and no knock sensor and has a carb. The timing
> advance is ported.
>
> When I run 91 octane gasoline, I only need the gas pedal to the floor
> on big hills, it will hold a nice 70-75 mph on the flats with about a
> half pedal.
>
> When the alcohol is added, it will only go over 65-70 mph on a down
> hill and to hold that 65 it needs to be right to the floor on the
> flats and geared down to 3rd on the hills. It sputters at idle too.
>
> I wasn't making the mileage numbers up, I drive by miles per tank
> because the gauge only sort of works.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
>

sounds like you are running quite lean or slightly retarted advance. that
is about the only explaniation as to why your milage and power drop off
that badly with only a 10% mix. KB

--
ThunderSnake #9 Warn once, shoot twice
460 in the pkup, 460 on the stand for another pkup
and one in the shed for a fun project to yet be decided on

Kevin Bottorff wrote:
>
> Mike Romain > wrote in
> :
>
> > Don Stauffer wrote:
> >>
> >> Jasper Janssen wrote:
> >> > On Sat, 07 May 2005 09:09:29 -0500, Don Stauffer
> >> > > wrote:
> >> >
> >> >
> >> >>However, I agree that the loss of hp in the 30 - 50% range is
> >> >>fiction.
> >> >
> >> >
> >> > He didn't say loss of HP, he said loss of mileage. If I read the
> >> > tables correctly, a gallon of alcohol contains less stored energy
> >> > than gasoline, so that's the right way to bet.
> >> >
> >> >
> >> >> Without raising the CR of the engine, one does loose a little hp.
> >> >> How
> >> >>much depends on whether engine has a knock sensor that will advance
> >> >>spark a bit on higher octane fuels.
> >> >
> >> >
> >> > Knock sensors never advance spark timing for higher octane fuels;
> >> > all they do is retard the timing if the octane is too low to
> >> > support the CR. Since that's never more efficient with a given fuel
> >> > than just having the right CR and the right timing, you don't
> >> > *want* the knock sensor to be used in that way.
> >> >
> >> > Jasper
> >>
> >> You're right- he did say milage, the hp in my statement was a goof.
> >> However, the amount of energy loss in a 15% mixture would create a
> >> 7.5% loss of milage, not 30-50%.
> >>
> >> And if the spark is retarded LESS on one fuel than another, then it
> >> is relatively ADVANCED compared to the second. Less retard is a
> >> relative advance.
> >
> > It comes down to derivability with the alcohol mixes. My engine has
> > no computer controls and no knock sensor and has a carb. The timing
> > advance is ported.
> >
> > When I run 91 octane gasoline, I only need the gas pedal to the floor
> > on big hills, it will hold a nice 70-75 mph on the flats with about a
> > half pedal.
> >
> > When the alcohol is added, it will only go over 65-70 mph on a down
> > hill and to hold that 65 it needs to be right to the floor on the
> > flats and geared down to 3rd on the hills. It sputters at idle too.
> >
> > I wasn't making the mileage numbers up, I drive by miles per tank
> > because the gauge only sort of works.
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
>
> sounds like you are running quite lean or slightly retarted advance. that
> is about the only explaniation as to why your milage and power drop off
> that badly with only a 10% mix. KB
>
> --

It is set basically like the book calls for. It's a stock Carter BBD
carb manually set up for 'best lean' idle mix and it does pass emissions
with great numbers. No catalytic converter and on the ASM 2525 test I
got 589 NOx, 16 ppm HC, 11% CO. The timing is the book settings around
8 deg with a ported advance. Plugs show normal burn and last well.

I have no idea of the mix quantities of the alcohol, they don't
advertise them on the pumps.

With good gas in it it will bury the speedo in 4th at 85 mph if there
isn't a bad headwind.

I just had a mix in and it was idling so bad I am doing a carb kit as we
speak, it is soaking. I filled up yesterday with good gas and only 1/4
tank of the mix left and it immediately started idling smooth again.
Already had the kit and it is due so I am cleaning it anyway....

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's