musing about fuel savings
09-25-2005, 05:37 PM
#41
Guest
Posts: n/a
Re: musing about fuel savings
Good analysis, Earle. Simplest way to test the theory would be to
pull one plug wire and see how you like it <g>.
As I am sure you can attest, the I6 is marginal above 10,000 ft.
anyway. Heck, 5th gear is useless without a 2% or better downhil
grade and/or a stiff tailwind.
Something everyone tends to ignore is that all the fancy systems
entail an auxilary cost that will quickly over-ride any savings in
fuel: maintainence. The more complex the system, the more frequent
(and expensive) the maintainence to keep it performing as designed.
On Sun, 25 Sep 2005 15:59:25 UTC "Earle Horton" <nursebusters@msn.com>
wrote:
> You would have to do the airflow analysis to convince me. Even though it
> looks as if each injector squirts its entire load of fuel into one and only
> one cylinder, I doubt that this is the case. What you would wind up with,
> is either a super-lean mixture every seventh cylinder, and that can't be
> good, or unburned fuel shot out the tail pipe. You have to have a means of
> bleeding off compression, and blocking the intake, maybe the exhaust, when
> you don't want a cylinder to fire. This makes it a lot more complicated,
> than simply reprogramming the ECM. In other words, a multi-displacement
> engine has to be designed from the ground up, in order to fulfill its
> intended purpose.
>
> What you could do, is get a four cylinder Jeep like I have, install a less
> restrictive intake and exhaust, and learn to drive wide open throttle like I
> do. This would get you up to 25 mpg, which will be a lot better than what
> you get now. I didn't say you shouldn't have a Jeep for the mileage, but I
> got pretty close. You need to get rid of that six cylinder thinking.
>
> Turbo City was working on a Jeep 4 cylinder turbo kit, but they abandoned it
> because of lack of anticipated demand. There are available supercharger
> kits for the 4 cylinder. Those are two ways of getting the same effect as
> multiple displacement. Another trick is to get the engine race-balanced and
> install forged pistons, so it can handle a couple thousand more RPM without
> getting hot oil and shrapnel all over your windshield.
>
> Earle
>
> "DougW" <post.replies@invalid.address> wrote in message
> news:UmzZe.7231$P34.655@okepread07...
> > Ok.. I know how the muli-displacement engines work, shutting down
> > fuel to half the bank. Which is easier for a V8.
> >
> > That got me thinking about the I6 4.0. It can run like a I3 but
> > that's only for balance testing, not for long runs. What tickled
> > the brain pan was the idea of dropping out one cyl on every rev.
> > Say the seventh cyl.. (yea, I know it has six)
> >
> > Normal firing order
> > 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> etc
> > Modified
> > 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> > X X X X X X
> >
> > 5/6 of the fuel would be used, but the question is what strain would
> > be put on the crank. I'm thinking it would be fairly nominal torsion.
> >
> > The only problem is dropping out a cyl could freak out the O2 sensor and
> > the next fuel load might be unnecessarily rich. A smoothing circuit
> > could fix that.
> >
> > Dropping out a fuel injector is easy. They are all fed by the ECM and
> > dropping out the ground connection is fairly easy.
> >
> > Thoughts.
> >
> > (other than if I wanted good gas mileage I shouldn't have got a Jeep) :)
> >
> >
> > This is what happens when I drink too much coffee before not going to
> > sleep. Yay coffee!
> >
> > --
> > DougW
> >
> >
> >
> >
> >
>
>
--
Will Honea
pull one plug wire and see how you like it <g>.
As I am sure you can attest, the I6 is marginal above 10,000 ft.
anyway. Heck, 5th gear is useless without a 2% or better downhil
grade and/or a stiff tailwind.
Something everyone tends to ignore is that all the fancy systems
entail an auxilary cost that will quickly over-ride any savings in
fuel: maintainence. The more complex the system, the more frequent
(and expensive) the maintainence to keep it performing as designed.
On Sun, 25 Sep 2005 15:59:25 UTC "Earle Horton" <nursebusters@msn.com>
wrote:
> You would have to do the airflow analysis to convince me. Even though it
> looks as if each injector squirts its entire load of fuel into one and only
> one cylinder, I doubt that this is the case. What you would wind up with,
> is either a super-lean mixture every seventh cylinder, and that can't be
> good, or unburned fuel shot out the tail pipe. You have to have a means of
> bleeding off compression, and blocking the intake, maybe the exhaust, when
> you don't want a cylinder to fire. This makes it a lot more complicated,
> than simply reprogramming the ECM. In other words, a multi-displacement
> engine has to be designed from the ground up, in order to fulfill its
> intended purpose.
>
> What you could do, is get a four cylinder Jeep like I have, install a less
> restrictive intake and exhaust, and learn to drive wide open throttle like I
> do. This would get you up to 25 mpg, which will be a lot better than what
> you get now. I didn't say you shouldn't have a Jeep for the mileage, but I
> got pretty close. You need to get rid of that six cylinder thinking.
>
> Turbo City was working on a Jeep 4 cylinder turbo kit, but they abandoned it
> because of lack of anticipated demand. There are available supercharger
> kits for the 4 cylinder. Those are two ways of getting the same effect as
> multiple displacement. Another trick is to get the engine race-balanced and
> install forged pistons, so it can handle a couple thousand more RPM without
> getting hot oil and shrapnel all over your windshield.
>
> Earle
>
> "DougW" <post.replies@invalid.address> wrote in message
> news:UmzZe.7231$P34.655@okepread07...
> > Ok.. I know how the muli-displacement engines work, shutting down
> > fuel to half the bank. Which is easier for a V8.
> >
> > That got me thinking about the I6 4.0. It can run like a I3 but
> > that's only for balance testing, not for long runs. What tickled
> > the brain pan was the idea of dropping out one cyl on every rev.
> > Say the seventh cyl.. (yea, I know it has six)
> >
> > Normal firing order
> > 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> etc
> > Modified
> > 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> > X X X X X X
> >
> > 5/6 of the fuel would be used, but the question is what strain would
> > be put on the crank. I'm thinking it would be fairly nominal torsion.
> >
> > The only problem is dropping out a cyl could freak out the O2 sensor and
> > the next fuel load might be unnecessarily rich. A smoothing circuit
> > could fix that.
> >
> > Dropping out a fuel injector is easy. They are all fed by the ECM and
> > dropping out the ground connection is fairly easy.
> >
> > Thoughts.
> >
> > (other than if I wanted good gas mileage I shouldn't have got a Jeep) :)
> >
> >
> > This is what happens when I drink too much coffee before not going to
> > sleep. Yay coffee!
> >
> > --
> > DougW
> >
> >
> >
> >
> >
>
>
--
Will Honea
09-25-2005, 05:37 PM
#42
Guest
Posts: n/a
Re: musing about fuel savings
Good analysis, Earle. Simplest way to test the theory would be to
pull one plug wire and see how you like it <g>.
As I am sure you can attest, the I6 is marginal above 10,000 ft.
anyway. Heck, 5th gear is useless without a 2% or better downhil
grade and/or a stiff tailwind.
Something everyone tends to ignore is that all the fancy systems
entail an auxilary cost that will quickly over-ride any savings in
fuel: maintainence. The more complex the system, the more frequent
(and expensive) the maintainence to keep it performing as designed.
On Sun, 25 Sep 2005 15:59:25 UTC "Earle Horton" <nursebusters@msn.com>
wrote:
> You would have to do the airflow analysis to convince me. Even though it
> looks as if each injector squirts its entire load of fuel into one and only
> one cylinder, I doubt that this is the case. What you would wind up with,
> is either a super-lean mixture every seventh cylinder, and that can't be
> good, or unburned fuel shot out the tail pipe. You have to have a means of
> bleeding off compression, and blocking the intake, maybe the exhaust, when
> you don't want a cylinder to fire. This makes it a lot more complicated,
> than simply reprogramming the ECM. In other words, a multi-displacement
> engine has to be designed from the ground up, in order to fulfill its
> intended purpose.
>
> What you could do, is get a four cylinder Jeep like I have, install a less
> restrictive intake and exhaust, and learn to drive wide open throttle like I
> do. This would get you up to 25 mpg, which will be a lot better than what
> you get now. I didn't say you shouldn't have a Jeep for the mileage, but I
> got pretty close. You need to get rid of that six cylinder thinking.
>
> Turbo City was working on a Jeep 4 cylinder turbo kit, but they abandoned it
> because of lack of anticipated demand. There are available supercharger
> kits for the 4 cylinder. Those are two ways of getting the same effect as
> multiple displacement. Another trick is to get the engine race-balanced and
> install forged pistons, so it can handle a couple thousand more RPM without
> getting hot oil and shrapnel all over your windshield.
>
> Earle
>
> "DougW" <post.replies@invalid.address> wrote in message
> news:UmzZe.7231$P34.655@okepread07...
> > Ok.. I know how the muli-displacement engines work, shutting down
> > fuel to half the bank. Which is easier for a V8.
> >
> > That got me thinking about the I6 4.0. It can run like a I3 but
> > that's only for balance testing, not for long runs. What tickled
> > the brain pan was the idea of dropping out one cyl on every rev.
> > Say the seventh cyl.. (yea, I know it has six)
> >
> > Normal firing order
> > 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> etc
> > Modified
> > 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> > X X X X X X
> >
> > 5/6 of the fuel would be used, but the question is what strain would
> > be put on the crank. I'm thinking it would be fairly nominal torsion.
> >
> > The only problem is dropping out a cyl could freak out the O2 sensor and
> > the next fuel load might be unnecessarily rich. A smoothing circuit
> > could fix that.
> >
> > Dropping out a fuel injector is easy. They are all fed by the ECM and
> > dropping out the ground connection is fairly easy.
> >
> > Thoughts.
> >
> > (other than if I wanted good gas mileage I shouldn't have got a Jeep) :)
> >
> >
> > This is what happens when I drink too much coffee before not going to
> > sleep. Yay coffee!
> >
> > --
> > DougW
> >
> >
> >
> >
> >
>
>
--
Will Honea
pull one plug wire and see how you like it <g>.
As I am sure you can attest, the I6 is marginal above 10,000 ft.
anyway. Heck, 5th gear is useless without a 2% or better downhil
grade and/or a stiff tailwind.
Something everyone tends to ignore is that all the fancy systems
entail an auxilary cost that will quickly over-ride any savings in
fuel: maintainence. The more complex the system, the more frequent
(and expensive) the maintainence to keep it performing as designed.
On Sun, 25 Sep 2005 15:59:25 UTC "Earle Horton" <nursebusters@msn.com>
wrote:
> You would have to do the airflow analysis to convince me. Even though it
> looks as if each injector squirts its entire load of fuel into one and only
> one cylinder, I doubt that this is the case. What you would wind up with,
> is either a super-lean mixture every seventh cylinder, and that can't be
> good, or unburned fuel shot out the tail pipe. You have to have a means of
> bleeding off compression, and blocking the intake, maybe the exhaust, when
> you don't want a cylinder to fire. This makes it a lot more complicated,
> than simply reprogramming the ECM. In other words, a multi-displacement
> engine has to be designed from the ground up, in order to fulfill its
> intended purpose.
>
> What you could do, is get a four cylinder Jeep like I have, install a less
> restrictive intake and exhaust, and learn to drive wide open throttle like I
> do. This would get you up to 25 mpg, which will be a lot better than what
> you get now. I didn't say you shouldn't have a Jeep for the mileage, but I
> got pretty close. You need to get rid of that six cylinder thinking.
>
> Turbo City was working on a Jeep 4 cylinder turbo kit, but they abandoned it
> because of lack of anticipated demand. There are available supercharger
> kits for the 4 cylinder. Those are two ways of getting the same effect as
> multiple displacement. Another trick is to get the engine race-balanced and
> install forged pistons, so it can handle a couple thousand more RPM without
> getting hot oil and shrapnel all over your windshield.
>
> Earle
>
> "DougW" <post.replies@invalid.address> wrote in message
> news:UmzZe.7231$P34.655@okepread07...
> > Ok.. I know how the muli-displacement engines work, shutting down
> > fuel to half the bank. Which is easier for a V8.
> >
> > That got me thinking about the I6 4.0. It can run like a I3 but
> > that's only for balance testing, not for long runs. What tickled
> > the brain pan was the idea of dropping out one cyl on every rev.
> > Say the seventh cyl.. (yea, I know it has six)
> >
> > Normal firing order
> > 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> etc
> > Modified
> > 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> > X X X X X X
> >
> > 5/6 of the fuel would be used, but the question is what strain would
> > be put on the crank. I'm thinking it would be fairly nominal torsion.
> >
> > The only problem is dropping out a cyl could freak out the O2 sensor and
> > the next fuel load might be unnecessarily rich. A smoothing circuit
> > could fix that.
> >
> > Dropping out a fuel injector is easy. They are all fed by the ECM and
> > dropping out the ground connection is fairly easy.
> >
> > Thoughts.
> >
> > (other than if I wanted good gas mileage I shouldn't have got a Jeep) :)
> >
> >
> > This is what happens when I drink too much coffee before not going to
> > sleep. Yay coffee!
> >
> > --
> > DougW
> >
> >
> >
> >
> >
>
>
--
Will Honea
09-25-2005, 05:37 PM
#43
Guest
Posts: n/a
Re: musing about fuel savings
Good analysis, Earle. Simplest way to test the theory would be to
pull one plug wire and see how you like it <g>.
As I am sure you can attest, the I6 is marginal above 10,000 ft.
anyway. Heck, 5th gear is useless without a 2% or better downhil
grade and/or a stiff tailwind.
Something everyone tends to ignore is that all the fancy systems
entail an auxilary cost that will quickly over-ride any savings in
fuel: maintainence. The more complex the system, the more frequent
(and expensive) the maintainence to keep it performing as designed.
On Sun, 25 Sep 2005 15:59:25 UTC "Earle Horton" <nursebusters@msn.com>
wrote:
> You would have to do the airflow analysis to convince me. Even though it
> looks as if each injector squirts its entire load of fuel into one and only
> one cylinder, I doubt that this is the case. What you would wind up with,
> is either a super-lean mixture every seventh cylinder, and that can't be
> good, or unburned fuel shot out the tail pipe. You have to have a means of
> bleeding off compression, and blocking the intake, maybe the exhaust, when
> you don't want a cylinder to fire. This makes it a lot more complicated,
> than simply reprogramming the ECM. In other words, a multi-displacement
> engine has to be designed from the ground up, in order to fulfill its
> intended purpose.
>
> What you could do, is get a four cylinder Jeep like I have, install a less
> restrictive intake and exhaust, and learn to drive wide open throttle like I
> do. This would get you up to 25 mpg, which will be a lot better than what
> you get now. I didn't say you shouldn't have a Jeep for the mileage, but I
> got pretty close. You need to get rid of that six cylinder thinking.
>
> Turbo City was working on a Jeep 4 cylinder turbo kit, but they abandoned it
> because of lack of anticipated demand. There are available supercharger
> kits for the 4 cylinder. Those are two ways of getting the same effect as
> multiple displacement. Another trick is to get the engine race-balanced and
> install forged pistons, so it can handle a couple thousand more RPM without
> getting hot oil and shrapnel all over your windshield.
>
> Earle
>
> "DougW" <post.replies@invalid.address> wrote in message
> news:UmzZe.7231$P34.655@okepread07...
> > Ok.. I know how the muli-displacement engines work, shutting down
> > fuel to half the bank. Which is easier for a V8.
> >
> > That got me thinking about the I6 4.0. It can run like a I3 but
> > that's only for balance testing, not for long runs. What tickled
> > the brain pan was the idea of dropping out one cyl on every rev.
> > Say the seventh cyl.. (yea, I know it has six)
> >
> > Normal firing order
> > 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> etc
> > Modified
> > 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> > X X X X X X
> >
> > 5/6 of the fuel would be used, but the question is what strain would
> > be put on the crank. I'm thinking it would be fairly nominal torsion.
> >
> > The only problem is dropping out a cyl could freak out the O2 sensor and
> > the next fuel load might be unnecessarily rich. A smoothing circuit
> > could fix that.
> >
> > Dropping out a fuel injector is easy. They are all fed by the ECM and
> > dropping out the ground connection is fairly easy.
> >
> > Thoughts.
> >
> > (other than if I wanted good gas mileage I shouldn't have got a Jeep) :)
> >
> >
> > This is what happens when I drink too much coffee before not going to
> > sleep. Yay coffee!
> >
> > --
> > DougW
> >
> >
> >
> >
> >
>
>
--
Will Honea
pull one plug wire and see how you like it <g>.
As I am sure you can attest, the I6 is marginal above 10,000 ft.
anyway. Heck, 5th gear is useless without a 2% or better downhil
grade and/or a stiff tailwind.
Something everyone tends to ignore is that all the fancy systems
entail an auxilary cost that will quickly over-ride any savings in
fuel: maintainence. The more complex the system, the more frequent
(and expensive) the maintainence to keep it performing as designed.
On Sun, 25 Sep 2005 15:59:25 UTC "Earle Horton" <nursebusters@msn.com>
wrote:
> You would have to do the airflow analysis to convince me. Even though it
> looks as if each injector squirts its entire load of fuel into one and only
> one cylinder, I doubt that this is the case. What you would wind up with,
> is either a super-lean mixture every seventh cylinder, and that can't be
> good, or unburned fuel shot out the tail pipe. You have to have a means of
> bleeding off compression, and blocking the intake, maybe the exhaust, when
> you don't want a cylinder to fire. This makes it a lot more complicated,
> than simply reprogramming the ECM. In other words, a multi-displacement
> engine has to be designed from the ground up, in order to fulfill its
> intended purpose.
>
> What you could do, is get a four cylinder Jeep like I have, install a less
> restrictive intake and exhaust, and learn to drive wide open throttle like I
> do. This would get you up to 25 mpg, which will be a lot better than what
> you get now. I didn't say you shouldn't have a Jeep for the mileage, but I
> got pretty close. You need to get rid of that six cylinder thinking.
>
> Turbo City was working on a Jeep 4 cylinder turbo kit, but they abandoned it
> because of lack of anticipated demand. There are available supercharger
> kits for the 4 cylinder. Those are two ways of getting the same effect as
> multiple displacement. Another trick is to get the engine race-balanced and
> install forged pistons, so it can handle a couple thousand more RPM without
> getting hot oil and shrapnel all over your windshield.
>
> Earle
>
> "DougW" <post.replies@invalid.address> wrote in message
> news:UmzZe.7231$P34.655@okepread07...
> > Ok.. I know how the muli-displacement engines work, shutting down
> > fuel to half the bank. Which is easier for a V8.
> >
> > That got me thinking about the I6 4.0. It can run like a I3 but
> > that's only for balance testing, not for long runs. What tickled
> > the brain pan was the idea of dropping out one cyl on every rev.
> > Say the seventh cyl.. (yea, I know it has six)
> >
> > Normal firing order
> > 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> etc
> > Modified
> > 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> > X X X X X X
> >
> > 5/6 of the fuel would be used, but the question is what strain would
> > be put on the crank. I'm thinking it would be fairly nominal torsion.
> >
> > The only problem is dropping out a cyl could freak out the O2 sensor and
> > the next fuel load might be unnecessarily rich. A smoothing circuit
> > could fix that.
> >
> > Dropping out a fuel injector is easy. They are all fed by the ECM and
> > dropping out the ground connection is fairly easy.
> >
> > Thoughts.
> >
> > (other than if I wanted good gas mileage I shouldn't have got a Jeep) :)
> >
> >
> > This is what happens when I drink too much coffee before not going to
> > sleep. Yay coffee!
> >
> > --
> > DougW
> >
> >
> >
> >
> >
>
>
--
Will Honea
09-25-2005, 05:37 PM
#44
Guest
Posts: n/a
Re: musing about fuel savings
Dave, how much of that fuel saving was attained by the impatient SOB
on your bumper so close he was actually pushing you along (or the air
pressure from his horn as he tried to speed you along)?
I got bored one day and ran a quick anaylsis of the drag effect of a
6x6 flat surface (fair aeordynamic representation of a Jeep). Just
figuring the total pressure was interesting. Air pressure varies with
the square of the velocity, at least for the speed range we are
talking about, so your results come pretty close to the energy
difference between pushing that 6x6 sheet of plywood at 65 vs. 75 mph.
I got similar results on a long trip - 600 miles with an average 30
mph tail wind vs the return trip with calm winds.
On Sun, 25 Sep 2005 18:53:09 UTC "Dave Milne"
<jeep@_nospam_milne.info> wrote:
> Been experimenting with exactly that. I used to get 19 mpg/US gallon at a
> carefree 75 mph and over the last 640 motorway miles, I have averaged a
> little over 24 mpg/US gallon at an "eggshell on the throttle peddle" 60-65
> mph. I was almost impressed with the TJs fuel consumption actually.
>
> Dave Milne, Scotland
> '91 Grand Wagoneer, '99 TJ
>
> "L.W. (ßill) ------ III" <----------@***.net> wrote in message
> news:4336DF20.48E4BB2E@***.net...
> > If you want to
> > save of fuel, drive slower and/or take the weight off the car.
>
>
--
Will Honea
on your bumper so close he was actually pushing you along (or the air
pressure from his horn as he tried to speed you along)?
I got bored one day and ran a quick anaylsis of the drag effect of a
6x6 flat surface (fair aeordynamic representation of a Jeep). Just
figuring the total pressure was interesting. Air pressure varies with
the square of the velocity, at least for the speed range we are
talking about, so your results come pretty close to the energy
difference between pushing that 6x6 sheet of plywood at 65 vs. 75 mph.
I got similar results on a long trip - 600 miles with an average 30
mph tail wind vs the return trip with calm winds.
On Sun, 25 Sep 2005 18:53:09 UTC "Dave Milne"
<jeep@_nospam_milne.info> wrote:
> Been experimenting with exactly that. I used to get 19 mpg/US gallon at a
> carefree 75 mph and over the last 640 motorway miles, I have averaged a
> little over 24 mpg/US gallon at an "eggshell on the throttle peddle" 60-65
> mph. I was almost impressed with the TJs fuel consumption actually.
>
> Dave Milne, Scotland
> '91 Grand Wagoneer, '99 TJ
>
> "L.W. (ßill) ------ III" <----------@***.net> wrote in message
> news:4336DF20.48E4BB2E@***.net...
> > If you want to
> > save of fuel, drive slower and/or take the weight off the car.
>
>
--
Will Honea
09-25-2005, 05:37 PM
#45
Guest
Posts: n/a
Re: musing about fuel savings
Dave, how much of that fuel saving was attained by the impatient SOB
on your bumper so close he was actually pushing you along (or the air
pressure from his horn as he tried to speed you along)?
I got bored one day and ran a quick anaylsis of the drag effect of a
6x6 flat surface (fair aeordynamic representation of a Jeep). Just
figuring the total pressure was interesting. Air pressure varies with
the square of the velocity, at least for the speed range we are
talking about, so your results come pretty close to the energy
difference between pushing that 6x6 sheet of plywood at 65 vs. 75 mph.
I got similar results on a long trip - 600 miles with an average 30
mph tail wind vs the return trip with calm winds.
On Sun, 25 Sep 2005 18:53:09 UTC "Dave Milne"
<jeep@_nospam_milne.info> wrote:
> Been experimenting with exactly that. I used to get 19 mpg/US gallon at a
> carefree 75 mph and over the last 640 motorway miles, I have averaged a
> little over 24 mpg/US gallon at an "eggshell on the throttle peddle" 60-65
> mph. I was almost impressed with the TJs fuel consumption actually.
>
> Dave Milne, Scotland
> '91 Grand Wagoneer, '99 TJ
>
> "L.W. (ßill) ------ III" <----------@***.net> wrote in message
> news:4336DF20.48E4BB2E@***.net...
> > If you want to
> > save of fuel, drive slower and/or take the weight off the car.
>
>
--
Will Honea
on your bumper so close he was actually pushing you along (or the air
pressure from his horn as he tried to speed you along)?
I got bored one day and ran a quick anaylsis of the drag effect of a
6x6 flat surface (fair aeordynamic representation of a Jeep). Just
figuring the total pressure was interesting. Air pressure varies with
the square of the velocity, at least for the speed range we are
talking about, so your results come pretty close to the energy
difference between pushing that 6x6 sheet of plywood at 65 vs. 75 mph.
I got similar results on a long trip - 600 miles with an average 30
mph tail wind vs the return trip with calm winds.
On Sun, 25 Sep 2005 18:53:09 UTC "Dave Milne"
<jeep@_nospam_milne.info> wrote:
> Been experimenting with exactly that. I used to get 19 mpg/US gallon at a
> carefree 75 mph and over the last 640 motorway miles, I have averaged a
> little over 24 mpg/US gallon at an "eggshell on the throttle peddle" 60-65
> mph. I was almost impressed with the TJs fuel consumption actually.
>
> Dave Milne, Scotland
> '91 Grand Wagoneer, '99 TJ
>
> "L.W. (ßill) ------ III" <----------@***.net> wrote in message
> news:4336DF20.48E4BB2E@***.net...
> > If you want to
> > save of fuel, drive slower and/or take the weight off the car.
>
>
--
Will Honea
09-25-2005, 05:37 PM
#46
Guest
Posts: n/a
Re: musing about fuel savings
Dave, how much of that fuel saving was attained by the impatient SOB
on your bumper so close he was actually pushing you along (or the air
pressure from his horn as he tried to speed you along)?
I got bored one day and ran a quick anaylsis of the drag effect of a
6x6 flat surface (fair aeordynamic representation of a Jeep). Just
figuring the total pressure was interesting. Air pressure varies with
the square of the velocity, at least for the speed range we are
talking about, so your results come pretty close to the energy
difference between pushing that 6x6 sheet of plywood at 65 vs. 75 mph.
I got similar results on a long trip - 600 miles with an average 30
mph tail wind vs the return trip with calm winds.
On Sun, 25 Sep 2005 18:53:09 UTC "Dave Milne"
<jeep@_nospam_milne.info> wrote:
> Been experimenting with exactly that. I used to get 19 mpg/US gallon at a
> carefree 75 mph and over the last 640 motorway miles, I have averaged a
> little over 24 mpg/US gallon at an "eggshell on the throttle peddle" 60-65
> mph. I was almost impressed with the TJs fuel consumption actually.
>
> Dave Milne, Scotland
> '91 Grand Wagoneer, '99 TJ
>
> "L.W. (ßill) ------ III" <----------@***.net> wrote in message
> news:4336DF20.48E4BB2E@***.net...
> > If you want to
> > save of fuel, drive slower and/or take the weight off the car.
>
>
--
Will Honea
on your bumper so close he was actually pushing you along (or the air
pressure from his horn as he tried to speed you along)?
I got bored one day and ran a quick anaylsis of the drag effect of a
6x6 flat surface (fair aeordynamic representation of a Jeep). Just
figuring the total pressure was interesting. Air pressure varies with
the square of the velocity, at least for the speed range we are
talking about, so your results come pretty close to the energy
difference between pushing that 6x6 sheet of plywood at 65 vs. 75 mph.
I got similar results on a long trip - 600 miles with an average 30
mph tail wind vs the return trip with calm winds.
On Sun, 25 Sep 2005 18:53:09 UTC "Dave Milne"
<jeep@_nospam_milne.info> wrote:
> Been experimenting with exactly that. I used to get 19 mpg/US gallon at a
> carefree 75 mph and over the last 640 motorway miles, I have averaged a
> little over 24 mpg/US gallon at an "eggshell on the throttle peddle" 60-65
> mph. I was almost impressed with the TJs fuel consumption actually.
>
> Dave Milne, Scotland
> '91 Grand Wagoneer, '99 TJ
>
> "L.W. (ßill) ------ III" <----------@***.net> wrote in message
> news:4336DF20.48E4BB2E@***.net...
> > If you want to
> > save of fuel, drive slower and/or take the weight off the car.
>
>
--
Will Honea
09-25-2005, 06:08 PM
#47
Guest
Posts: n/a
Re: musing about fuel savings
Well ya know, if that would work in the slightest degree, one of the
makers would have tried it eh.......
Figure what the engine runs like with one plug wire off and just figure
on that power hit once every 7 shots. Shutting one cylinder down on a
conventional engine just doesn't work and Caddy proved shutting down
cylinders works for ----.
I hear the new crippled Hemi, that has no right to that name has a
serious power lag while the computer thinks about what cylinder to fire
when it is new and it is 'fly by wire' with no cables, imagine when it
ages....
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
DougW wrote:
>
> Ok.. I know how the muli-displacement engines work, shutting down
> fuel to half the bank. Which is easier for a V8.
>
> That got me thinking about the I6 4.0. It can run like a I3 but
> that's only for balance testing, not for long runs. What tickled
> the brain pan was the idea of dropping out one cyl on every rev.
> Say the seventh cyl.. (yea, I know it has six)
>
> Normal firing order
> 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 etc
> Modified
> 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> X X X X X X
>
> 5/6 of the fuel would be used, but the question is what strain would
> be put on the crank. I'm thinking it would be fairly nominal torsion.
>
> The only problem is dropping out a cyl could freak out the O2 sensor and
> the next fuel load might be unnecessarily rich. A smoothing circuit
> could fix that.
>
> Dropping out a fuel injector is easy. They are all fed by the ECM and
> dropping out the ground connection is fairly easy.
>
> Thoughts.
>
> (other than if I wanted good gas mileage I shouldn't have got a Jeep) :)
>
> This is what happens when I drink too much coffee before not going to
> sleep. Yay coffee!
>
> --
> DougW
makers would have tried it eh.......
Figure what the engine runs like with one plug wire off and just figure
on that power hit once every 7 shots. Shutting one cylinder down on a
conventional engine just doesn't work and Caddy proved shutting down
cylinders works for ----.
I hear the new crippled Hemi, that has no right to that name has a
serious power lag while the computer thinks about what cylinder to fire
when it is new and it is 'fly by wire' with no cables, imagine when it
ages....
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
DougW wrote:
>
> Ok.. I know how the muli-displacement engines work, shutting down
> fuel to half the bank. Which is easier for a V8.
>
> That got me thinking about the I6 4.0. It can run like a I3 but
> that's only for balance testing, not for long runs. What tickled
> the brain pan was the idea of dropping out one cyl on every rev.
> Say the seventh cyl.. (yea, I know it has six)
>
> Normal firing order
> 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 etc
> Modified
> 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> X X X X X X
>
> 5/6 of the fuel would be used, but the question is what strain would
> be put on the crank. I'm thinking it would be fairly nominal torsion.
>
> The only problem is dropping out a cyl could freak out the O2 sensor and
> the next fuel load might be unnecessarily rich. A smoothing circuit
> could fix that.
>
> Dropping out a fuel injector is easy. They are all fed by the ECM and
> dropping out the ground connection is fairly easy.
>
> Thoughts.
>
> (other than if I wanted good gas mileage I shouldn't have got a Jeep) :)
>
> This is what happens when I drink too much coffee before not going to
> sleep. Yay coffee!
>
> --
> DougW
09-25-2005, 06:08 PM
#48
Guest
Posts: n/a
Re: musing about fuel savings
Well ya know, if that would work in the slightest degree, one of the
makers would have tried it eh.......
Figure what the engine runs like with one plug wire off and just figure
on that power hit once every 7 shots. Shutting one cylinder down on a
conventional engine just doesn't work and Caddy proved shutting down
cylinders works for ----.
I hear the new crippled Hemi, that has no right to that name has a
serious power lag while the computer thinks about what cylinder to fire
when it is new and it is 'fly by wire' with no cables, imagine when it
ages....
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
DougW wrote:
>
> Ok.. I know how the muli-displacement engines work, shutting down
> fuel to half the bank. Which is easier for a V8.
>
> That got me thinking about the I6 4.0. It can run like a I3 but
> that's only for balance testing, not for long runs. What tickled
> the brain pan was the idea of dropping out one cyl on every rev.
> Say the seventh cyl.. (yea, I know it has six)
>
> Normal firing order
> 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 etc
> Modified
> 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> X X X X X X
>
> 5/6 of the fuel would be used, but the question is what strain would
> be put on the crank. I'm thinking it would be fairly nominal torsion.
>
> The only problem is dropping out a cyl could freak out the O2 sensor and
> the next fuel load might be unnecessarily rich. A smoothing circuit
> could fix that.
>
> Dropping out a fuel injector is easy. They are all fed by the ECM and
> dropping out the ground connection is fairly easy.
>
> Thoughts.
>
> (other than if I wanted good gas mileage I shouldn't have got a Jeep) :)
>
> This is what happens when I drink too much coffee before not going to
> sleep. Yay coffee!
>
> --
> DougW
makers would have tried it eh.......
Figure what the engine runs like with one plug wire off and just figure
on that power hit once every 7 shots. Shutting one cylinder down on a
conventional engine just doesn't work and Caddy proved shutting down
cylinders works for ----.
I hear the new crippled Hemi, that has no right to that name has a
serious power lag while the computer thinks about what cylinder to fire
when it is new and it is 'fly by wire' with no cables, imagine when it
ages....
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
DougW wrote:
>
> Ok.. I know how the muli-displacement engines work, shutting down
> fuel to half the bank. Which is easier for a V8.
>
> That got me thinking about the I6 4.0. It can run like a I3 but
> that's only for balance testing, not for long runs. What tickled
> the brain pan was the idea of dropping out one cyl on every rev.
> Say the seventh cyl.. (yea, I know it has six)
>
> Normal firing order
> 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 etc
> Modified
> 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> X X X X X X
>
> 5/6 of the fuel would be used, but the question is what strain would
> be put on the crank. I'm thinking it would be fairly nominal torsion.
>
> The only problem is dropping out a cyl could freak out the O2 sensor and
> the next fuel load might be unnecessarily rich. A smoothing circuit
> could fix that.
>
> Dropping out a fuel injector is easy. They are all fed by the ECM and
> dropping out the ground connection is fairly easy.
>
> Thoughts.
>
> (other than if I wanted good gas mileage I shouldn't have got a Jeep) :)
>
> This is what happens when I drink too much coffee before not going to
> sleep. Yay coffee!
>
> --
> DougW
09-25-2005, 06:08 PM
#49
Guest
Posts: n/a
Re: musing about fuel savings
Well ya know, if that would work in the slightest degree, one of the
makers would have tried it eh.......
Figure what the engine runs like with one plug wire off and just figure
on that power hit once every 7 shots. Shutting one cylinder down on a
conventional engine just doesn't work and Caddy proved shutting down
cylinders works for ----.
I hear the new crippled Hemi, that has no right to that name has a
serious power lag while the computer thinks about what cylinder to fire
when it is new and it is 'fly by wire' with no cables, imagine when it
ages....
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
DougW wrote:
>
> Ok.. I know how the muli-displacement engines work, shutting down
> fuel to half the bank. Which is easier for a V8.
>
> That got me thinking about the I6 4.0. It can run like a I3 but
> that's only for balance testing, not for long runs. What tickled
> the brain pan was the idea of dropping out one cyl on every rev.
> Say the seventh cyl.. (yea, I know it has six)
>
> Normal firing order
> 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 etc
> Modified
> 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> X X X X X X
>
> 5/6 of the fuel would be used, but the question is what strain would
> be put on the crank. I'm thinking it would be fairly nominal torsion.
>
> The only problem is dropping out a cyl could freak out the O2 sensor and
> the next fuel load might be unnecessarily rich. A smoothing circuit
> could fix that.
>
> Dropping out a fuel injector is easy. They are all fed by the ECM and
> dropping out the ground connection is fairly easy.
>
> Thoughts.
>
> (other than if I wanted good gas mileage I shouldn't have got a Jeep) :)
>
> This is what happens when I drink too much coffee before not going to
> sleep. Yay coffee!
>
> --
> DougW
makers would have tried it eh.......
Figure what the engine runs like with one plug wire off and just figure
on that power hit once every 7 shots. Shutting one cylinder down on a
conventional engine just doesn't work and Caddy proved shutting down
cylinders works for ----.
I hear the new crippled Hemi, that has no right to that name has a
serious power lag while the computer thinks about what cylinder to fire
when it is new and it is 'fly by wire' with no cables, imagine when it
ages....
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
DougW wrote:
>
> Ok.. I know how the muli-displacement engines work, shutting down
> fuel to half the bank. Which is easier for a V8.
>
> That got me thinking about the I6 4.0. It can run like a I3 but
> that's only for balance testing, not for long runs. What tickled
> the brain pan was the idea of dropping out one cyl on every rev.
> Say the seventh cyl.. (yea, I know it has six)
>
> Normal firing order
> 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 etc
> Modified
> 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4 1-5-3-6-2-4
> X X X X X X
>
> 5/6 of the fuel would be used, but the question is what strain would
> be put on the crank. I'm thinking it would be fairly nominal torsion.
>
> The only problem is dropping out a cyl could freak out the O2 sensor and
> the next fuel load might be unnecessarily rich. A smoothing circuit
> could fix that.
>
> Dropping out a fuel injector is easy. They are all fed by the ECM and
> dropping out the ground connection is fairly easy.
>
> Thoughts.
>
> (other than if I wanted good gas mileage I shouldn't have got a Jeep) :)
>
> This is what happens when I drink too much coffee before not going to
> sleep. Yay coffee!
>
> --
> DougW
09-25-2005, 06:34 PM
#50
Guest
Posts: n/a
Re: musing about fuel savings
Well, no impatient SOBs actually. The truckers here are a lot slower than in
the US, doing 55-65 mph, so if you are polite and flash them to let them
know when they have over taken you enough, they give you a friendly wave or
left-right-left flash of the indicators.
Your truckers are downright scary when you are in a jeep doing 80 up a
hill... and can only see the letters "AC" of "Mack" in your rear view mirror
:-).
Dave Milne, Scotland
'91 Grand Wagoneer, '99 TJ
"Will Honea" <whonea@yahoo.com> wrote in message
news:JxX2tWiP5BNp-pn2-VbCwduROPchX@anon.none.net...
> Dave, how much of that fuel saving was attained by the impatient SOB
> on your bumper so close he was actually pushing you along (or the air
> pressure from his horn as he tried to speed you along)?
>
> I got bored one day and ran a quick anaylsis of the drag effect of a
> 6x6 flat surface (fair aeordynamic representation of a Jeep). Just
> figuring the total pressure was interesting. Air pressure varies with
> the square of the velocity, at least for the speed range we are
> talking about, so your results come pretty close to the energy
> difference between pushing that 6x6 sheet of plywood at 65 vs. 75 mph.
>
> I got similar results on a long trip - 600 miles with an average 30
> mph tail wind vs the return trip with calm winds.
>
> On Sun, 25 Sep 2005 18:53:09 UTC "Dave Milne"
> <jeep@_nospam_milne.info> wrote:
>
> > Been experimenting with exactly that. I used to get 19 mpg/US gallon at
a
> > carefree 75 mph and over the last 640 motorway miles, I have averaged a
> > little over 24 mpg/US gallon at an "eggshell on the throttle peddle"
60-65
> > mph. I was almost impressed with the TJs fuel consumption actually.
> >
> > Dave Milne, Scotland
> > '91 Grand Wagoneer, '99 TJ
> >
> > "L.W. (ßill) ------ III" <----------@***.net> wrote in message
> > news:4336DF20.48E4BB2E@***.net...
> > > If you want to
> > > save of fuel, drive slower and/or take the weight off the car.
> >
> >
>
>
> --
> Will Honea
the US, doing 55-65 mph, so if you are polite and flash them to let them
know when they have over taken you enough, they give you a friendly wave or
left-right-left flash of the indicators.
Your truckers are downright scary when you are in a jeep doing 80 up a
hill... and can only see the letters "AC" of "Mack" in your rear view mirror
:-).
Dave Milne, Scotland
'91 Grand Wagoneer, '99 TJ
"Will Honea" <whonea@yahoo.com> wrote in message
news:JxX2tWiP5BNp-pn2-VbCwduROPchX@anon.none.net...
> Dave, how much of that fuel saving was attained by the impatient SOB
> on your bumper so close he was actually pushing you along (or the air
> pressure from his horn as he tried to speed you along)?
>
> I got bored one day and ran a quick anaylsis of the drag effect of a
> 6x6 flat surface (fair aeordynamic representation of a Jeep). Just
> figuring the total pressure was interesting. Air pressure varies with
> the square of the velocity, at least for the speed range we are
> talking about, so your results come pretty close to the energy
> difference between pushing that 6x6 sheet of plywood at 65 vs. 75 mph.
>
> I got similar results on a long trip - 600 miles with an average 30
> mph tail wind vs the return trip with calm winds.
>
> On Sun, 25 Sep 2005 18:53:09 UTC "Dave Milne"
> <jeep@_nospam_milne.info> wrote:
>
> > Been experimenting with exactly that. I used to get 19 mpg/US gallon at
a
> > carefree 75 mph and over the last 640 motorway miles, I have averaged a
> > little over 24 mpg/US gallon at an "eggshell on the throttle peddle"
60-65
> > mph. I was almost impressed with the TJs fuel consumption actually.
> >
> > Dave Milne, Scotland
> > '91 Grand Wagoneer, '99 TJ
> >
> > "L.W. (ßill) ------ III" <----------@***.net> wrote in message
> > news:4336DF20.48E4BB2E@***.net...
> > > If you want to
> > > save of fuel, drive slower and/or take the weight off the car.
> >
> >
>
>
> --
> Will Honea