OT - Fuel consumption

[Geoff May]

Can anyone tell me why my fuel consumption in summer is lower than in
winter?

In summer, I get 37mpg to 39mpg but in winter, I struggle to get above
35mpg and it is usually around 33mpg. I'm basing these figures on my
drive to work and back everyday and the conditions (traffic or driving
style) do not change as the time taken to do the trip remains about 65
minutes each way.

Cheers

Geoff

[Alan LeHun]

In article <kkhirh$mbj$1...@speranza.aioe.org>,
GeoffMay_do...@nospam.com says...

> In summer, I get 37mpg to 39mpg but in winter, I struggle to get above
> 35mpg and it is usually around 33mpg. I'm basing these figures on my
> drive to work and back everyday and the conditions (traffic or driving
> style) do not change as the time taken to do the trip remains about 65
> minutes each way.
>

More energy required to power vehicle electrics would be my guess.

--
Alan LeHun
Reply-to is valid. Add "BPSF" to subject: to bypass spam filters.

[AC]

Are you drinking it to keep warm?

Doesn't the fuel system put more fuel through or run richer when its
cold? Also, olde days you pulled the choke out and used more fuel as the
engine warmed up, doesn't the ECU do similar?

I might be very wrong, but that's what I sort of assumed.

Heating or air con? Driving style?

Also, are you 10000000000% sure the traffic is exactly the same? Round
here there is slightly less traffic, there for less stop start in the
summer because kids are either off school or more likely to walk or
cycle. Not just kids, but less cars in the railway car-park as workers
are more likely to walk to the station.

Oh yeah, fuckers who think they are Olympians, loads of those here.
(remember I live on the London Olympic cycle route and there has been a
massive increase in middle aged men on damn push bikes heaving their fat
arses around the place)

Combine all that lot,a nd you probably have your answer.

Personally, I cant say I've noticed much difference. Although, out fuel
prices are such a mare I don't really know what Im using. I try to
ignore it. I have what I think is the most acceptable and efficient car
I can reasonably live with, and just pay the sodding fuel bill. In fact
I just put the same money value in and make it do. Whole thing pisses me
off TBH. If I could, I not bother with a car at all. Its almost like
being a criminal or whipping boy. Worse still, a whore ewe.

--
AC

[John Briggs]

Engines run much more efficiently when running hot. For that reason, my
father used to hang a piece of hardboard to block off part of the
radiator. (Come the day when my parents went on an early holiday,
leaving me to drive the car pool to work, and the weather turned
warmer...) Even so, it will take quite a time for the engine to warm up
fully. Thing are exacerbated these day by catalytic convertors, which
take a *long* time to get up to a working temperature, and affect the
fuel efficiency when not at working temperature. Fuel efficiency is also
worse when road are wet - apparently this is mostly due to increased
friction. I would hazard a guess that you trip would need to increase by
20% (probably a lot more) to get comparable fuel efficiency. I would
suggest the main fact is ambient temperature. (Using the car heater
reduces fuel efficiency - except in summer - as the heat is not totally
"free".)
--
John Briggs

[mick]

Cold air is heavier than warm air so it takes more fuel to power
through it.
Winter = lights on, heater on, heavier clothing all equal more fuel
used
Summer = shorts on, sunglasses on, lost your winter fat all equal less
fuel.
:-)

--
mick

[Steve Thompson]

On Mon, 15 Apr 2013, Geoff May wrote:

> In summer, I get 37mpg to 39mpg but in winter, I struggle to get above 35mpg
> and it is usually around 33mpg.

The fuel formulation changes with the season.

-steve

[Grant]

"John Briggs" <john.b...@ntlworld.com> wrote in message
news:mAYat.496$U97...@fx31.fr7...

> On 15/04/2013 20:02, Geoff May wrote:
>> Can anyone tell me why my fuel consumption in summer is lower than in
>> winter?
>>
>> In summer, I get 37mpg to 39mpg but in winter, I struggle to get above
>> 35mpg and it is usually around 33mpg. I'm basing these figures on my
>> drive to work and back everyday and the conditions (traffic or driving
>> style) do not change as the time taken to do the trip remains about 65
>> minutes each way.
>
> Engines run much more efficiently when running hot.

Only if the engine is old and worn and the heat is needed for expansion of
the moving part to seal valves and piston rings etc.
>
Hot engines generally produce less power as the friction levels are higher.
>
Engines have an optimum temperature, that's why they have thermostats to
regulate cooling.

[Bobster]

On Apr 15, 11:29 pm, mick <no.s...@junk.mail> wrote:
> > Can anyone tell me why my fuel consumption in summer is lower than in winter?
>
> > In summer, I get 37mpg to 39mpg but in winter, I struggle to get above 35mpg
> > and it is usually around 33mpg. I'm basing these figures on my drive to work
> > and back everyday and the conditions (traffic or driving style) do not change
> > as the time taken to do the trip remains about 65 minutes each way.
>
> > Cheers
>
> > Geoff
>
> Cold air is heavier than warm air so it takes more fuel to power
> through it.

But you get more power, no? We've heard from time to time how F1 cars
have more power when it's cool because they are taking more air in.
OK... maybe more power means more fuel, but it should also mean you
don't have to push the pedal as much.

> Winter = lights on, heater on, heavier clothing all equal more fuel
> used

Depending on conditions where you live. I should watch to see what
happens to my consumption as we go into winter here. I try not to use
aircon, but in the summer there are times when you can't get away from
it.

But in the winter it's darker in the mornings so I use my headlights
more.

Aarrrgh! Brain exploding.

[~misfit~]

Somewhere on teh intarwebs mick wrote:
>> Can anyone tell me why my fuel consumption in summer is lower than
>> in winter? In summer, I get 37mpg to 39mpg but in winter, I struggle to
>> get
>> above 35mpg and it is usually around 33mpg. I'm basing these figures
>> on my drive to work and back everyday and the conditions (traffic or
>> driving style) do not change as the time taken to do the trip
>> remains about 65 minutes each way. Cheers
>>
>> Geoff
>
> Cold air is heavier than warm air so it takes more fuel to power
> through it.

Not just cold air - Humid air is considerably denser. I don't know if the
humidity is higher in winter - mick didn't say where he is.

However here in NZ we've just had the hottest, driest summer for at least 70
years. In the last few days however, for the first time since last winter,
we've had some rain and the temperature has dropped around 10 C in a week.
Also, here just south of Auckland the humidity is about 95%.

I've just got back from a trip up the motorway and it feels like my (little
old boxy) car is about 5 - 10% down on power. After quite a bit of thought I
put most of that down to the density of the air that my car was pushing out
of its way.

> Winter = lights on, heater on, heavier clothing all equal more fuel
> used
> Summer = shorts on, sunglasses on, lost your winter fat all equal less
> fuel.
> :-)

Heh, there's that too. A couple of years ago I retro-fitted 6 x 1 watt [7.5K
colour-temp] LEDs to serve as 'DRLs'. They make my car much more visible in
gloomy weather than other cars that have their headlights on for a lot less
fuel consumption. :)
--
/Shaun.

"Humans will have advanced a long, long, way when religious belief has a
cozy little classification in the DSM."
David Melville (in r.a.s.f1)

[Alan Baker]

In article <kkijqd$n0l$1...@dont-email.me>,

"~misfit~" <shaun.at...@gmail.com> wrote:

> Somewhere on teh intarwebs mick wrote:
> >> Can anyone tell me why my fuel consumption in summer is lower than
> >> in winter? In summer, I get 37mpg to 39mpg but in winter, I struggle to
> >> get
> >> above 35mpg and it is usually around 33mpg. I'm basing these figures
> >> on my drive to work and back everyday and the conditions (traffic or
> >> driving style) do not change as the time taken to do the trip
> >> remains about 65 minutes each way. Cheers
> >>
> >> Geoff
> >
> > Cold air is heavier than warm air so it takes more fuel to power
> > through it.
>
> Not just cold air - Humid air is considerably denser. I don't know if the
> humidity is higher in winter - mick didn't say where he is.

Actually, you're incorrect about humid air being denser. Humid air is
LESS dense because the H20 molecule is less massive than either the O2
or the N2 molecules that make up the bulk of our atmosphere.

<http://www.theweatherprediction.com/habyhints/260/>

>
> However here in NZ we've just had the hottest, driest summer for at least 70
> years. In the last few days however, for the first time since last winter,
> we've had some rain and the temperature has dropped around 10 C in a week.
> Also, here just south of Auckland the humidity is about 95%.
>
> I've just got back from a trip up the motorway and it feels like my (little
> old boxy) car is about 5 - 10% down on power. After quite a bit of thought I
> put most of that down to the density of the air that my car was pushing out
> of its way.
>
> > Winter = lights on, heater on, heavier clothing all equal more fuel
> > used
> > Summer = shorts on, sunglasses on, lost your winter fat all equal less
> > fuel.
> > :-)
>
> Heh, there's that too. A couple of years ago I retro-fitted 6 x 1 watt [7.5K
> colour-temp] LEDs to serve as 'DRLs'. They make my car much more visible in
> gloomy weather than other cars that have their headlights on for a lot less
> fuel consumption. :)

--

Alan Baker
Vancouver, British Columbia
"If you raise the ceiling four feet, move the fireplace from that wall
to that wall, you'll still only get the full stereophonic effect if you
sit in the bottom of that cupboard."

[AC]

Alan Baker wrote:
> In article <kkijqd$n0l$1...@dont-email.me>,
> "~misfit~" <shaun.at...@gmail.com> wrote:
>
>> Somewhere on teh intarwebs mick wrote:
>>>> Can anyone tell me why my fuel consumption in summer is lower than
>>>> in winter? In summer, I get 37mpg to 39mpg but in winter, I struggle to
>>>> get
>>>> above 35mpg and it is usually around 33mpg. I'm basing these figures
>>>> on my drive to work and back everyday and the conditions (traffic or
>>>> driving style) do not change as the time taken to do the trip
>>>> remains about 65 minutes each way. Cheers
>>>>
>>>> Geoff
>>>
>>> Cold air is heavier than warm air so it takes more fuel to power
>>> through it.
>>
>> Not just cold air - Humid air is considerably denser. I don't know if the
>> humidity is higher in winter - mick didn't say where he is.
>
> Actually, you're incorrect about humid air being denser. Humid air is
> LESS dense because the H20 molecule is less massive than either the O2
> or the N2 molecules that make up the bulk of our atmosphere.
>
> <http://www.theweatherprediction.com/habyhints/260/>
>

I, in my ignorance, I think I can see a hair split there.

It could be said that the air is more dense, since air is not, er, an
actual defined thing. So when its humid, the air is still air, but it
has more water in it. So, less oxygen. The air is denser, but it is
denser because, for a given volume, it has more water and less oxygen.
So, it is less oxygen dense, but over all more dense because of the
water. (yeah, too much dense going on to avoid a joke!!)

So, what defines "air". If it is what is sucked in by the induction
system, then it is including any water that is in that air, right?

Or very wrong????!!!!

But, what about the thing where it is or used to be said with olde cars,
you got more power when its raining?

Anyway, any of that right?

--
AC

[Bobster]

On Apr 16, 9:53 am, AC <x...@xxx.xxx> wrote:
<snip>

> But, what about the thing where it is or used to be said with olde cars,
> you got more power when its raining?

I think that was more a case of not noticing the power deficiency in
wet conditions because the guys with the more potent cars are giving
it less welly.

[Bigbird]

Fuel facts

To help drivers understand better the impact of winter driving on their
fuel bills, the AA Fuel for Thought campaign offers the following facts:

The heated rear window uses around two per cent extra fuel. If both
the front and rear heated screens are used the increase in fuel
consumption equates to six per cent as heated front screens consume
more power than the rear screen.
Even at a relatively mild outside temperature of +10C, a car's fuel
consumption for the first mile will be around 40 per cent higher than
with a warmed-up engine. This falls to around 16 per cent over the next
three miles and, even up to 6.5 miles from start-up, fuel consumption
can be 8 per cent higher.
The increase in fuel consumption due to cold weather is similar for
both diesel and petrol cars. AA tests show extra fuel use after 1 mile
and 3 miles respectively are:
typical small petrol car � 34% and 17%
medium petrol car � 38% and 16%
small diesel car � 32% and 12%
medium diesel car � 43% and 18%
For demisting windows and getting the cabin comfortable, basic air
conditioning on a small car can increase fuel consumption by up to 10
per cent. A more powerful petrol engine will suffer less, as will a
larger diesel.
Getting stuck in a traffic jam is another daily problem with winter
driving. Even with a warmed-up engine, a petrol car can lose at least
two-thirds to three-quarters of a litre of fuel every hour, or 1.2 to
1.4p a minute. A diesel car can lose a third to half a litre of fuel an
hour, or 0.6 to 1.0p a minute.

NB Wearing sunglasses has little effect on fuel consumption. Relative
to a kerb weight of say 1500kg wearing a thermal vest will have
negligible effect on fuel consumption.

[Alan Baker]

Not really, no.

[Alan LeHun]

In article <Nr7bt.2485$z82...@fx07.fr7>, x...@xxx.xxx says...

> The air is denser, but it is
> denser because, for a given volume, it has more water and less oxygen.
> So, it is less oxygen dense, but over all more dense because of the
> water. (yeah, too much dense going on to avoid a joke!!)
>
>

And completely arse about tit. Water is light, almost half the weight of
oxygen, so increased humidity would make the air less dense.

[Bigbird]

Alan LeHun wrote:

> In article <Nr7bt.2485$z82...@fx07.fr7>, x...@xxx.xxx says...
> > The air is denser, but it is
> > denser because, for a given volume, it has more water and less
> > oxygen. So, it is less oxygen dense, but over all more dense
> > because of the water. (yeah, too much dense going on to avoid a
> > joke!!)
> >
> >
>
> And completely arse about tit. Water is light, almost half the weight
> of oxygen, so increased humidity would make the air less dense.

32 > 18

All that oxygen lying around on the bottom of the pool going to waste?.?

[Joaquín Topiso]

On Monday, April 15, 2013 8:02:10 PM UTC+1, Geoff May wrote:
> Can anyone tell me why my fuel consumption in summer is lower than in
>
> winter?
>
>

Two main reasons:

-Different fuel spec summer/winter
-Different air density.

In winter more O2 gets into the engine, so you can put in more fuel with the same lambda value. You have more power in winter, thus higher consumption.
You might think you don´t use that extra power, but you might be getting away slightly quicker from every single traffic light.

Regards,

JT

[Alan LeHun]

In article <kkk0vo$pc1$1...@dont-email.me>, Bigbird.us...@Gmail.com
says...

> > And completely arse about tit. Water is light, almost half the weight
> > of oxygen, so increased humidity would make the air less dense.
>
> 32 > 18
>
> All that oxygen lying around on the bottom of the pool going to waste?.?
>

:)
The trick is to get them both into the same state at the same time.


Have we not discussed all this before? Courtesy of DC I believe. Maybe
it was somewhere else.

[Bigbird]

Alan LeHun wrote:

> In article <kkk0vo$pc1$1...@dont-email.me>,
> Bigbird.us...@Gmail.com says...
> > > And completely arse about tit. Water is light, almost half the
> > > weight of oxygen, so increased humidity would make the air less
> > > dense.
> >
> > 32 > 18
> >
> > All that oxygen lying around on the bottom of the pool going to
> > waste?.?
> >
>
> :)
> The trick is to get them both into the same state at the same time.
>
>
> Have we not discussed all this before? Courtesy of DC I believe.
> Maybe it was somewhere else.

I can't remember my schoolboy chemistry but my maths says you still
have to explain how you reckon 32 is less than 18.

[Mark Jackson]

On 4/16/2013 5:15 PM, Bigbird wrote:
> Alan LeHun wrote:
>
>> In article <kkk0vo$pc1$1...@dont-email.me>,
>> Bigbird.us...@Gmail.com says...
>>>> And completely arse about tit. Water is light, almost half the
>>>> weight of oxygen, so increased humidity would make the air less
>>>> dense.
>>>
>>> 32 > 18
>>>
>>> All that oxygen lying around on the bottom of the pool going to
>>> waste?.?
>>>
>>
>> :)
>> The trick is to get them both into the same state at the same time.
>>
>>
>> Have we not discussed all this before? Courtesy of DC I believe.
>> Maybe it was somewhere else.
>
> I can't remember my schoolboy chemistry

Really? Then where did "32" and "18" come from?

> but my maths says you still
> have to explain how you reckon 32 is less than 18.

Air is not pure oxygen. From
http://wahiduddin.net/calc/density_altitude.htm:

> Md = molecular weight of dry air = 28.964 gm/mol
> Mv = molecular weight of water vapor = 18.016 gm/mol

--
Mark Jackson - http://www.alumni.caltech.edu/~mjackson
Some day, historians are going to look back on the 2012
Republican presidential campaign and think that we made it all up.
- Charles P. Pierce

[Mower Man]

Quicker warm up. Simples.

--
Chris

'Fashion is a form of ugliness so intolerable that we have to alter it
every six months.'

(Oscar Wilde.)

[Mower Man]

Remove all the lights/heater stuff and:

Cold air more dense = more power.
But... cold air = slower warm up.
So, long run in cold air = lower fuel consumption given the same speed.
Short run in cold air = higher fuel consumption as engine never reaches
optimum temperature.

All of these are of course gross over simplifications!

[Alan Baker]

In article <kkkj63$pdf$1...@speranza.aioe.org>,

Mower Man <chris...@nospamf2s.com> wrote:

> On 15/04/2013 10:29 PM, mick wrote:
> >> Can anyone tell me why my fuel consumption in summer is lower than in
> >> winter?
> >>
> >> In summer, I get 37mpg to 39mpg but in winter, I struggle to get above
> >> 35mpg and it is usually around 33mpg. I'm basing these figures on my
> >> drive to work and back everyday and the conditions (traffic or driving
> >> style) do not change as the time taken to do the trip remains about 65
> >> minutes each way.
> >>
> >> Cheers
> >>
> >> Geoff
> >
> > Cold air is heavier than warm air so it takes more fuel to power through
> > it.
> > Winter = lights on, heater on, heavier clothing all equal more fuel used
> > Summer = shorts on, sunglasses on, lost your winter fat all equal less
> > fuel.
> > :-)
> >
>
> Remove all the lights/heater stuff and:
>
> Cold air more dense = more power.
> But... cold air = slower warm up.
> So, long run in cold air = lower fuel consumption given the same speed.
> Short run in cold air = higher fuel consumption as engine never reaches
> optimum temperature.
>
> All of these are of course gross over simplifications!

They certainly are.

Cold air is denser than warm air, yes. That means that at the same
speed, drag and the power needed to overcome that drag both increase. It
also means that power at any given engine speed and throttle opening is
greater because the quantity (mass) of air in the cylinder on each
stroke will be greater, but to yield that greater power means burning
more fuel.

So the answer to fuel economy being greater in winter is not nearly so
simple... ...assuming it's even true.

[Bigbird]

Mark Jackson wrote:

> On 4/16/2013 5:15 PM, Bigbird wrote:
> > Alan LeHun wrote:
> >
> > > In article <kkk0vo$pc1$1...@dont-email.me>,
> > > Bigbird.us...@Gmail.com says...
> > > > > And completely arse about tit. Water is light, almost half the
> > > > > weight of oxygen, so increased humidity would make the air
> > > > > less dense.
> > > >
> >>>32 > 18
> > > >
> > > > All that oxygen lying around on the bottom of the pool going to
> > > > waste?.?
> > > >
> > >
> > > :)
> > > The trick is to get them both into the same state at the same
> > > time.
> > >
> > >
> > > Have we not discussed all this before? Courtesy of DC I believe.
> > > Maybe it was somewhere else.
> >
> > I can't remember my schoolboy chemistry
>
> Really? Then where did "32" and "18" come from?
>

Kindergarden.

> > but my maths says you still
> > have to explain how you reckon 32 is less than 18.
>
> Air is not pure oxygen.

Not even close,

http://www.engineeringtoolbox.com/molecular-mass-air-d_679.html

> but

"Water is light, almost half the weight of oxygen"

Hence 18 and 32.

[Alan LeHun]

In article <kkkf1i$69o$1...@dont-email.me>, Bigbird.us...@Gmail.com
says...

>
> Alan LeHun wrote:
>
> > In article <kkk0vo$pc1$1...@dont-email.me>,
> > Bigbird.us...@Gmail.com says...
> > > > And completely arse about tit. Water is light, almost half the
> > > > weight of oxygen, so increased humidity would make the air less
> > > > dense.
> > >
> > > 32 > 18

Yep. That is correct. 32 is indeed more than 18.

> > >
> > > All that oxygen lying around on the bottom of the pool going to
> > > waste?.?
> > >
> >
> > :)
> > The trick is to get them both into the same state at the same time.
> >
> >
> > Have we not discussed all this before? Courtesy of DC I believe.
> > Maybe it was somewhere else.
>
> I can't remember my schoolboy chemistry but my maths says you still
> have to explain how you reckon 32 is less than 18.

H2O (that's water) = 1 + 1 + 16 =18
O2 (that's Oxygen) = 16 + 16 = 32

So water has a mw of 18 and Oxygen has a mw of 32

I'm not sure why I have to explain why 32 is less than 18 as my position
as implied by my statement is that 18 is almost half of 32. I stand by
that assertion.

[larkim]

http://wiki.answers.com/Q/Is_oxygen_heavier_than_water

Matt

[WrongWayWade]

> Or very wrong????!!!!

Yes, very wrong. The 'experience' of being in hot, humid air makes it feel
like it is denser, but it is just the opposite. All 'air' molecules take up
the same space effectively at any particular temperature, no matter if they
are O2, N2, H2O or Ar. O2 has an molecule weight of ~32, N2 is ~28, Ar is
~40, H20 is only ~18. Humid air is much less dense than dry air. Golf
balls, baseballs go farther in humid air, all other things being the same,
because of the reduced air resistance (less weight to push out of the way.)

Whether engines run more efficiently with dry vs. humid air, I have no idea.

[Geoff May]

On 16/04/2013 15:33, Bigbird wrote:
> [snipped]

To everyone who responded, thank you :-) Makes for interesting reading.

Cheers

Geoff

[Mike P]

On Mon, 15 Apr 2013 20:02:10 +0100, Geoff May wrote:

> Can anyone tell me why my fuel consumption in summer is lower than in
> winter?

Because your car takes longer to warm up, and isn't as efficient when the
engine is cold. There's also the extra load things like the electric
windows/heated seats/heater/lights will use - though I believe that's
negligble if your battery is in good condition anyway. Simply because it
takes longer to warm the engine up.



--
Mike P

[WrongWayWade]

Mike P wrote:
> On Mon, 15 Apr 2013 20:02:10 +0100, Geoff May wrote:
>
>> Can anyone tell me why my fuel consumption in summer is lower than in
>> winter?

My experience is the opposite. I live in the South of the US and it's so
hot and humid in the summer you must run the air conditioning all the time.
This costs much more than any window heating or driving through rain or
extra headlight use in the winter, and I probably get 2mpg less in the
summer than the winter. But with modern engines there really is no need to
'warm them up', at least to the extent of idling for 5-10 minutes before
driving. Just start it, wait 5 seconds and drive. Whether it's inefficient
in those first few minutes, could be.

[Mike P]

On Wed, 17 Apr 2013 15:32:48 -0400, WrongWayWade wrote:

> Mike P wrote:
>> On Mon, 15 Apr 2013 20:02:10 +0100, Geoff May wrote:
>>
>>> Can anyone tell me why my fuel consumption in summer is lower than in
>>> winter?
>
> My experience is the opposite. I live in the South of the US and it's
> so hot and humid in the summer you must run the air conditioning all the
> time. This costs much more than any window heating or driving through
> rain or extra headlight use in the winter, and I probably get 2mpg less
> in the summer than the winter.

My sister-in-law lives in Phenix, AL. That's South. My cousins live in
Mississippi.

You guys don't get winter. It gets a bit chilly, that's about all. I know
they had snow for the first time in years and years last year for about a
day..




--
Mike P

[Noj]

WrongWayWade wrote ...

>
> Mike P wrote:
> > On Mon, 15 Apr 2013 20:02:10 +0100, Geoff May wrote:
> >
> >> Can anyone tell me why my fuel consumption in summer is lower than in
> >> winter?
>
> My experience is the opposite. I live in the South of the US and it's so
> hot and humid in the summer you must run the air conditioning all the time.
> This costs much more than any window heating or driving through rain or
> extra headlight use in the winter, and I probably get 2mpg less in the
> summer than the winter. But with modern engines there really is no need to
> 'warm them up', at least to the extent of idling for 5-10 minutes before
> driving. Just start it, wait 5 seconds and drive. Whether it's inefficient
> in those first few minutes, could be.

With petrol at 10 bob a gallon, I doubt if you care about MPG.

[Mower Man]

On a LONG run , ok? You are demonstrating that as an engineer you have
all the predicyive skills of an economist. Guess what that is?

[Alan Baker]

In article <kkn477$fmu$1...@speranza.aioe.org>,

I don't know what you might be getting at.

But the facts I gave you are just that: facts.

If you do 30mph through denser air, that will require more power. Even
if you don't have to open the throttle as wide because the air is denser
and thus you're getting more air into the cylinder to provide that
power, you'll be mixing that air with more fuel or else you won't GET
more power.

[~misfit~]

Handy to know, thanks.

> Whether engines run more efficiently with dry vs. humid air, I have
> no idea.

I have always been told that humid 'air' is better for power. <shrug> I've
already been wrong once in this thread though. ;)
--
/Shaun.

"Humans will have advanced a long, long, way when religious belief has a
cozy little classification in the DSM."
David Melville (in r.a.s.f1)

[~misfit~]

Somewhere on teh intarwebs Alan Baker wrote:
> In article <kkijqd$n0l$1...@dont-email.me>,
> "~misfit~" <shaun.at...@gmail.com> wrote:

[snips]

>> Not just cold air - Humid air is considerably denser. I don't know
>> if the humidity is higher in winter - mick didn't say where he is.
>
> Actually, you're incorrect about humid air being denser. Humid air is
> LESS dense because the H20 molecule is less massive than either the O2
> or the N2 molecules that make up the bulk of our atmosphere.
>
> <http://www.theweatherprediction.com/habyhints/260/>

Cheers. It must have been the ~10 degree C cooler air since I made my last
motorway trip that made (some of) the difference then...

[Grant]

"Alan Baker" <alang...@telus.net> wrote in message
news:alangbaker-8C4EC...@news.shawcable.net...

Drag at low to normal road speeds is almost insignificant.
>
What no one seems to have mentioned is rolling resistance, warmer weather
undoubtedly results in higher tyre pressures thus reducing rolling
risistance which is a major fuel draw.
>
Oh and dense air has more oxygen molecules which does equal more power and a
cleaner burn for a given amount of fuel. Fuel injected engines, once the
engine is up to temperature will not inject more fuel because the air temp
is low. Carburettors may allow more fuel if the air is denser.
>
Another factor is the pump at the filling station, may be effected by
temperature.

[Alan Baker]

In article <I8ednTseEK9tUvLM...@giganews.com>,

" Grant" <Gr...@Mcleod40.fsnet.co.ku.com> wrote:

> >> On a LONG run , ok? You are demonstrating that as an engineer you have
> >> all the predicyive skills of an economist. Guess what that is?
> >
> > I don't know what you might be getting at.
> >
> > But the facts I gave you are just that: facts.
> >
> > If you do 30mph through denser air, that will require more power. Even
> > if you don't have to open the throttle as wide because the air is denser
> > and thus you're getting more air into the cylinder to provide that
> > power, you'll be mixing that air with more fuel or else you won't GET
> > more power.
> >
> >
> Drag at low to normal road speeds is almost insignificant.

If highway speeds are normal, air drag is most definitely NOT

insignificant.

> >
> What no one seems to have mentioned is rolling resistance, warmer weather
> undoubtedly results in higher tyre pressures thus reducing rolling
> risistance which is a major fuel draw.

Unless you check your tire pressures periodically...

> >
> Oh and dense air has more oxygen molecules which does equal more power and a
> cleaner burn for a given amount of fuel. Fuel injected engines, once the
> engine is up to temperature will not inject more fuel because the air temp
> is low. Carburettors may allow more fuel if the air is denser.

No. It does not. Because the fuel is inject to MATCH to mass of air.

> >
> Another factor is the pump at the filling station, may be effected by
> temperature.

[Bigbird]

Mike P wrote:

> On Mon, 15 Apr 2013 20:02:10 +0100, Geoff May wrote:
>
> > Can anyone tell me why my fuel consumption in summer is lower than
> > in winter?
>
> Because your car takes longer to warm up, and isn't as efficient when
> the engine is cold. There's also the extra load things like the
> electric windows/heated seats/heater/lights will use - though I
> believe that's negligble if your battery is in good condition anyway.

Free energy?

[Bigbird]

What's going to be more significant; the change in aire density or the
change in rolling resistance due to lower temps? Are either the
significant factors in relation to the OP?

[Alan Baker]

In article <kkqm9j$o5c$1...@dont-email.me>,

I don't know (words that for some reason lots of people on Usenet seem
to have trouble saying), but what I do know is that there is no free
lunch. People have been arguing that denser air means more power as if
you get that power without burning more fuel...

...and it just doesn't work that way.

[Noj]

Alan Baker wrote ...

<Snippery do da>

.
> >
> > What's going to be more significant; the change in aire density or the
> > change in rolling resistance due to lower temps? Are either the
> > significant factors in relation to the OP?
>
> I don't know (words that for some reason lots of people on Usenet seem
> to have trouble saying), but what I do know is that there is no free
> lunch. People have been arguing that denser air means more power as if
> you get that power without burning more fuel...
>
> ...and it just doesn't work that way.

Sure?

Really sure ?

https://en.wikipedia.org/wiki/Cold_air_intake

[Alan Baker]

In article <MPG.2bdb016d1...@news.shared-secrets.com>,

Noj <b...@arse.com> wrote:

> Alan Baker wrote ...
>
> <Snippery do da>
> .
> > >
> > > What's going to be more significant; the change in aire density or the
> > > change in rolling resistance due to lower temps? Are either the
> > > significant factors in relation to the OP?
> >
> > I don't know (words that for some reason lots of people on Usenet seem
> > to have trouble saying), but what I do know is that there is no free
> > lunch. People have been arguing that denser air means more power as if
> > you get that power without burning more fuel...
> >
> > ...and it just doesn't work that way.
>
>
> Sure?

Yup.

>
> Really sure ?

Really.

>
> https://en.wikipedia.org/wiki/Cold_air_intake

Tell you what: you quote the part of that page that contradicts what
I've said.

I'll wait.

[Bigbird]

Alan Baker wrote:

> In article <MPG.2bdb016d1...@news.shared-secrets.com>,
> Noj <b...@arse.com> wrote:
>
> > Alan Baker wrote ...
> >
> > <Snippery do da>
> > .
> > > >
> > > > What's going to be more significant; the change in aire density
> > > > or the change in rolling resistance due to lower temps? Are
> > > > either the significant factors in relation to the OP?
> > >
> > > I don't know (words that for some reason lots of people on Usenet
> > > seem to have trouble saying), but what I do know is that there is
> > > no free lunch. People have been arguing that denser air means
> > > more power as if you get that power without burning more fuel...
> > >
> > > ...and it just doesn't work that way.
> >
> >
> > Sure?
>
> Yup.
>
> >
> > Really sure ?
>
> Really.
>
> >
> > https://en.wikipedia.org/wiki/Cold_air_intake
>
> Tell you what: you quote the part of that page that contradicts what
> I've said.
>
> I'll wait.

I'll give it a shot.

"Aftermarket cold air intake systems are marketed with claims of
increased engine efficiency..."

Your criticism certainly implies you do not think this the case.

[Alan Baker]

In article <kkr0mb$iah$1...@dont-email.me>,

And stating that people make claims about things is hardly proof that
those claims are true.

Next.

[Noj]

Bigbird wrote ...

Been here before with this nob - looks like a replacement for the drunk.

[Bigbird]

Don't be so quick, you're in reverse.

[Alan Baker]

In article <MPG.2bdb2973...@news.shared-secrets.com>,

LOL

[Alan Baker]

In article <kkr69c$kkt$1...@dont-email.me>,

It doesn't contradict what I've said, though.

I've never said that people don't claim it.

[Bigbird]

<sigh>

Fuckwit!

[Alan Baker]

In article <kkrt8k$sps$1...@dont-email.me>,

Look: you've failed to show how the article contradicts anything I've
said. Be a man and simply admit failure.

:-)

[News]

Give up, 'Bird. Next he'll bring up max tensile loading on con-rods!

[Alan Baker]

I'll ask you the same question:

What in that Wikipedia article contradicts what I've said?

So far, we've been given:

""Aftermarket cold air intake systems are marketed with CLAIMS of
increased engine efficiency..."

And that doesn't contradict anything I've said.

What I've said, BTW, is that there is no free lunch. In colder air, does
an engine make more power at a given throttle opening and RPM? Yes. Does
that make it more efficient in fuel consumption? No.

[News]

Keep flapping.

[Alan Baker]

So, no substantive answer to my question, then?

[News]

Not my debate, skippy. Suit yourself.

[Mower Man]

Might BMEP have any effect? It's the baseline.

[Alan Baker]

You inserted yourself, and then suddenly got coy.

[News]

My comment was to 'Bird. You decided to hijack the comment and
interject a reply.

[alan]

On Apr 19, 2:26 pm, News <N...@Group.Post> wrote:
> On 4/19/2013 5:20 PM, Alan Baker wrote:
>
>
>
>
>
>
>
>
>
> > In article <kks44a$gp...@dont-email.me>, News <N...@Group.Post> wrote:
>
> >> On 4/19/2013 2:54 PM, Alan Baker wrote:

> >>> In article <kks3bn$br...@dont-email.me>, News <N...@Group.Post> wrote:
>
> >>>> On 4/19/2013 2:15 PM, Alan Baker wrote:

> >>>>> In article <kks08k$jf...@dont-email.me>, News <N...@Group.Post> wrote:
>
> >>>>>> On 4/19/2013 1:45 PM, Alan Baker wrote:

> >>>>>>> In article <kkrt8k$sp...@dont-email.me>,

You replied to my post. And even if you hadn't, you walked up to two
people talking and inserted yourself in the conversation.

Deal with it.

[News]

GFYA

[Alan Baker]

Wow! Such erudition!

[Alan Baker]

In article <kks8g5$m77$1...@speranza.aioe.org>,

Nope.

[Bigbird]

Wow! Such a fragile ego!

[Bigbird]

<Alan Baker mode>

He didn't walk up to anyone. The "conversation" was over before his
addition. You were given the bird for being a fuckwit.

All your claims are worthless. You haven't proved anything. Your
contradictions of others posts are nonsense.

</Alan Baker mode>

You're wrong. You know it and you're no good at this. Consider panto.

[Alan Baker]

In article <kktbhv$mtq$1...@dont-email.me>,

Really? How so?

I've told you the facts and asked for what information you (or others)
believe contradicts me.

So far... ...I've been given back nothing of substance.

[Alan Baker]

In article <kktbsn$ofl$1...@dont-email.me>,

LOL

[News]

Fit for intended purpose.

[Alan Baker]

I'm sure you believe that...

LOL

[News]

It got the intended rise out of you, fuckwit. LOLz back at ya.

[Alan Baker]

In article <kkunm5$caq$1...@dont-email.me>, News <Ne...@Group.Post> wrote:

> >>>>>> My comment was to 'Bird. You decided to hijack the comment and
> >>>>>> interject a reply.
> >>>>>
> >>>>> You replied to my post. And even if you hadn't, you walked up to two
> >>>>> people talking and inserted yourself in the conversation.
> >>>>>
> >>>>> Deal with it.
> >>>>>
> >>>>
> >>>>
> >>>> GFYA
> >>>
> >>> Wow! Such erudition!
> >>>
> >>
> >>
> >> Fit for intended purpose.
> >
> > I'm sure you believe that...
> >
> > LOL
> >
>
>
> It got the intended rise out of you, fuckwit. LOLz back at ya.

It did?

Another legend in his own mind...

[News]

On 4/20/2013 4:53 PM, Alan Baker wrote:
> In article <kkunm5$caq$1...@dont-email.me>, News <Ne...@Group.Post> wrote:
>
>>>>>>>> My comment was to 'Bird. You decided to hijack the comment and
>>>>>>>> interject a reply.
>>>>>>>
>>>>>>> You replied to my post. And even if you hadn't, you walked up to two
>>>>>>> people talking and inserted yourself in the conversation.
>>>>>>>
>>>>>>> Deal with it.
>>>>>>>
>>>>>>
>>>>>>
>>>>>> GFYA
>>>>>
>>>>> Wow! Such erudition!
>>>>>
>>>>
>>>>
>>>> Fit for intended purpose.
>>>
>>> I'm sure you believe that...
>>>
>>> LOL
>>>
>>
>>
>> It got the intended rise out of you, fuckwit. LOLz back at ya.
>
> It did?
>
> Another legend in his own mind...
>

Fuckwit elicited on cue: "Wow! Such erudition!"

[Alan Baker]

LOL

And this shows... ...what?

[News]

On 4/20/2013 10:14 PM, Alan Baker wrote:
> In article <kkv0b4$9av$1...@dont-email.me>, News <Ne...@Group.Post> wrote:
>
>> On 4/20/2013 4:53 PM, Alan Baker wrote:
>>> In article <kkunm5$caq$1...@dont-email.me>, News <Ne...@Group.Post> wrote:
>>>
>>>>>>>>>> My comment was to 'Bird. You decided to hijack the comment and
>>>>>>>>>> interject a reply.
>>>>>>>>>
>>>>>>>>> You replied to my post. And even if you hadn't, you walked up to two
>>>>>>>>> people talking and inserted yourself in the conversation.
>>>>>>>>>
>>>>>>>>> Deal with it.
>>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> GFYA
>>>>>>>
>>>>>>> Wow! Such erudition!
>>>>>>>
>>>>>>
>>>>>>
>>>>>> Fit for intended purpose.
>>>>>
>>>>> I'm sure you believe that...
>>>>>
>>>>> LOL
>>>>>
>>>>
>>>>
>>>> It got the intended rise out of you, fuckwit. LOLz back at ya.
>>>
>>> It did?
>>>
>>> Another legend in his own mind...
>>>
>>
>> Fuckwit elicited on cue: "Wow! Such erudition!"
>
> LOL
>
> And this shows... ...what?
>

That you're even dumber than appears.

[Alan Baker]

LOL

Again, I'll ask you:

What statements in this Wikipedia article:

<https://en.wikipedia.org/wiki/Cold_air_intake>

...contradict anything I've said?

[News]

Why not ask someone who gives a shyte?

[Alan Baker]

You "gave a shyte" enough to butt in to the conversation...

...now you're punking out?

[News]

Hardly; you are being played like a drum.

[Noj]

Alan Baker wrote ...

> >
> > Why not ask someone who gives a shyte?
>
> You "gave a shyte" enough to butt in to the conversation...
>

This is Usenet - not email or a phone call. Anyone can make a comment
as and when they see fit.

[Alan Baker]

Riiiiiiight.

I'M being played!

LOL

[Alan Baker]

In article <MPG.2bdf6c7f2...@news.shared-secrets.com>,

Yup. That's all true.

And it changes nothing in what I said.

:-)

[News]

Thanks for playing. Again.

[Alan Baker]

LOL

He thinks I'M being played!

[News]

This would be hilarious, if it were not so sad.

<You> cannot possibly be the issue, it must be <anyone else>.

A reaction not unlike Nathan Thurm, SNL character played by Martin Short.

A shady lawyer, Thurm was a chain-smoker, quite paranoid, and constantly
in denial about his paranoia. "I'm not being defensive. You're the one
who's being defensive."

When questioned, his catch phrase often included, "It's so funny to me
that you would think..." He would also look into the camera and express
his puzzlement at the questioner by asking, "Is it me, or is it him? ...
It's him, right?"

Other times, he would deny an accusation, then immediately reverse his
position when the accuser reaffirmed the statement. "No, it isn't!"
("Yes it is.") "I know that! Why wouldn't I know that? I'm well aware of
that!"

Imagine: http://www.youtube.com/watch?v=FOLBQxk72NY

<rimshot>

[~misfit~]

Somewhere on teh intarwebs Alan Baker wrote:
> In article <kl1qqg$m30$1...@dont-email.me>, News <Ne...@Group.Post> wrote:

[snips]

>> Why not ask someone who gives a shyte?
>
> You "gave a shyte" enough to butt in to the conversation...

This ceased to be a 'conversation' as such quite a few days ago.

> ...now you're punking out?

Oh, you like arguing on usenet, got it. May I suggest
alt.fan.karl.maldens.nose?
--
/Shaun.

"Humans will have advanced a long, long, way when religious belief has a
cozy little classification in the DSM."
David Melville (in r.a.s.f1)

[Alan Baker]

In article <kl4qcs$4af$1...@dont-email.me>,

"~misfit~" <shaun.at...@gmail.com> wrote:

> Somewhere on teh intarwebs Alan Baker wrote:
> > In article <kl1qqg$m30$1...@dont-email.me>, News <Ne...@Group.Post> wrote:
> [snips]
> >> Why not ask someone who gives a shyte?
> >
> > You "gave a shyte" enough to butt in to the conversation...
>
> This ceased to be a 'conversation' as such quite a few days ago.
>
> > ...now you're punking out?
>
> Oh, you like arguing on usenet, got it. May I suggest
> alt.fan.karl.maldens.nose?

I'd rather have intelligent conversation on the topic...

...but when I tried that I got nothing intelligent in return.

Literally nothing.

[Sir Tim]

On 23/04/2013 08:20, Alan Baker wrote:
> In article <kl4qcs$4af$1...@dont-email.me>,
> "~misfit~" <shaun.at...@gmail.com> wrote:
>
>> Somewhere on teh intarwebs Alan Baker wrote:
>>> In article <kl1qqg$m30$1...@dont-email.me>, News <Ne...@Group.Post> wrote:
>> [snips]
>>>> Why not ask someone who gives a shyte?
>>>
>>> You "gave a shyte" enough to butt in to the conversation...
>>
>> This ceased to be a 'conversation' as such quite a few days ago.
>>
>>> ...now you're punking out?
>>
>> Oh, you like arguing on usenet, got it. May I suggest
>> alt.fan.karl.maldens.nose?
>
> I'd rather have intelligent conversation on the topic...
>
> ...but when I tried that I got nothing intelligent in return.
>
> Literally nothing.
>

So why not be adult about it and abandon the thread? You don't *have* to
have the last word you know

[Noj]

Sir Tim wrote ...

Oh yes he does...

[Alan Baker]

In article <kKqdnWp5xolZ_uvM...@brightview.co.uk>,

How do you know I haven't?

Have you seen another reply from me to News's last post?

:-)

[Mower Man]

On 18/04/2013 1:06 AM, Alan Baker wrote:
> In article <kkn477$fmu$1...@speranza.aioe.org>,
> Mower Man <chris...@nospamf2s.com> wrote:
>
>> On 17/04/2013 1:49 AM, Alan Baker wrote:
>>> In article <kkkj63$pdf$1...@speranza.aioe.org>,
>>> Mower Man <chris...@nospamf2s.com> wrote:
>>>
>>>> On 15/04/2013 10:29 PM, mick wrote:
>>>>>> Can anyone tell me why my fuel consumption in summer is lower than in
>>>>>> winter?
>>>>>>
>>>>>> In summer, I get 37mpg to 39mpg but in winter, I struggle to get above
>>>>>> 35mpg and it is usually around 33mpg. I'm basing these figures on my
>>>>>> drive to work and back everyday and the conditions (traffic or driving
>>>>>> style) do not change as the time taken to do the trip remains about 65
>>>>>> minutes each way.
>>>>>>
>>>>>> Cheers
>>>>>>
>>>>>> Geoff
>>>>>
>>>>> Cold air is heavier than warm air so it takes more fuel to power through
>>>
>>
>> On a LONG run , ok? You are demonstrating that as an engineer you have
>> all the predictive skills of an economist. Guess what that is?
>
> I don't know what you might be getting at.

Economists - like marketing "experts/professionals" are simply a waste
of space. Agreed? Look at what Japan is now proposing? A very different
idea. It might well work. I do hope so.

Whereas in Harry Ricardo's terms the laws of BMEP will always be real.



> But the facts I gave you are just that: facts.
>
> If you do 30mph through denser air, that will require more power. Even
> if you don't have to open the throttle as wide because the air is denser
> and thus you're getting more air into the cylinder to provide that
> power, you'll be mixing that air with more fuel or else you won't GET
> more power.

Yes to all of the above - but is it not PROPORTIONATE? I.e., how much
more power vs. how much more drag?

Do tell us - for a given temperature drop and a given air density (and
yes, water content has an effect) - what might a graph showing the
resultant power output look like?



--
Chris

'Fashion is a form of ugliness so intolerable that we have to alter it
every six months.'

(Oscar Wilde.)

[Alan Baker]

In article <kl9kc4$4f0$1...@speranza.aioe.org>,

And please describe how those "laws" are in conflict with anything I've
said...

>
>
>
> > But the facts I gave you are just that: facts.
> >
> > If you do 30mph through denser air, that will require more power. Even
> > if you don't have to open the throttle as wide because the air is denser
> > and thus you're getting more air into the cylinder to provide that
> > power, you'll be mixing that air with more fuel or else you won't GET
> > more power.
>
> Yes to all of the above - but is it not PROPORTIONATE? I.e., how much
> more power vs. how much more drag?
>
> Do tell us - for a given temperature drop and a given air density (and
> yes, water content has an effect) - what might a graph showing the
> resultant power output look like?

It doesn't matter.

Does driving through denser air take more power? Yes.

In order to get more power, is simply getting more air into each
cylinder at a given rpm and throttle opening enough? No.

You do get more air into the cylinders when the air is denser and that
does mean you can make more power...

...but you only get that power by mixing more gasoline with that
increase in air.

[Noj]

Alan Baker wrote ...

Denser means more ?
That's a new law of physics is it ?

Here's another link that you can ignore
http://usatoday30.usatoday.com/weather/wdensity.htm

[Mower Man]

C'mon, you can do better than that. (Or maybe not)

So colder denser air will produce more power.

And it will produce more drag.

But how much more power? How much more drag? Do they cancel each other
out, is that what you're saying?

I find that utterly improbable. Prove it, if that's what you mean.

[Alan Baker]

In article <MPG.2be3c4d3c...@news.shared-secrets.com>,

In the context of how much drag is generated by moving through it,
denser air creates more drag (everything else being equal).

I the context of getting air into the cylinders, denser air means
more... ...everything else being equal.

> That's a new law of physics is it ?
>
> Here's another link that you can ignore
> http://usatoday30.usatoday.com/weather/wdensity.htm

Tell you what: you go ahead and quote the part that you claim
contradicts anything I've said...

You'll pardon me if I don't hold my breath.

[Alan Baker]

In article <klccr5$hor$1...@speranza.aioe.org>,

By allowing you to burn more fuel, yes.

>
> And it will produce more drag.
>
> But how much more power? How much more drag? Do they cancel each other
> out, is that what you're saying?

Nope. The more drag is the important bit.

More drag requires more power.

More power requires more fuel to be burnt.

>
> I find that utterly improbable. Prove it, if that's what you mean.

Since it's not what I mean...

[Noj]

That statement wins you the 2013 Thick As Shit Award.

[Alan Baker]

In article <MPG.2be3cd389...@news.shared-secrets.com>,

And you an explain why you think that is, can you?

>
>
> >
> > > That's a new law of physics is it ?
> > >
> > > Here's another link that you can ignore
> > > http://usatoday30.usatoday.com/weather/wdensity.htm
> >
> > Tell you what: you go ahead and quote the part that you claim
> > contradicts anything I've said...
> >
> > You'll pardon me if I don't hold my breath.

That's what I thought.

[Alan LeHun]

In article <MPG.2be3c4d3c...@news.shared-secrets.com>,
b...@arse.com says...

> Here's another link that you can ignore
> http://usatoday30.usatoday.com/weather/wdensity.htm
>

Thank you for that informative link. Having spent the past 15 seconds or
so thoroughly digesting the wealth of information therein I now know,
that all other things being equal, denser means more.


--
Alan LeHun
Reply-to is valid. Add "BPSF" to subject: to bypass spam filters.

[Alan Baker]

In article <MPG.2be3d8065...@news-europe.giganews.com>,

Alan LeHun <t...@reply.to> wrote:

> In article <MPG.2be3c4d3c...@news.shared-secrets.com>,
> b...@arse.com says...
>
> > Here's another link that you can ignore
> > http://usatoday30.usatoday.com/weather/wdensity.htm
> >
>
> Thank you for that informative link. Having spent the past 15 seconds or
> so thoroughly digesting the wealth of information therein I now know,
> that all other things being equal, denser means more.

I know!

I mean, who'd have thought!

;-)

[Mower Man]

Total fail, sorry.

What exactly DO you mean then?

My point is that colder conditions will NOT affect ALL aspects of power,
drag etc. equally.

Any thoughts?