Just had my engine dyno'd and air fuel ratio checked
#51
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
Well, let me just say this. At this time in my break in process, the my
BUTT Dyno sees little difference between the previous 4.2 and the current
setup.
After a couple of thousand miles I'll let you know how it feels then.
Bill
"serg" <none@none.com> wrote in message
news:rmUsc.57116$y%3.49430@newssvr29.news.prodigy. com...
> thanks for posting the results! i've been wondering about the power gains
> using a 4.0 head. i'm going to take mine in too when i'm finally done
with
> it.
>
> "William Oliveri" <wuji@bigvalley.net> wrote in message
> news:2hhg59Fd4rv0U1@uni-berlin.de...
> > 4.2 block / 4.0 Head.
> >
> > Results: 124.9 Horsepower. I should have about 160, yes?
> >
> > Air/Fuel ratio came back a tad lean if anything.
> >
> > Engine has about 60 miles on it.
> >
> > Mechanic told me there's nothing wrong with the injectors.
> >
> > Bill
> >
> >
>
>
BUTT Dyno sees little difference between the previous 4.2 and the current
setup.
After a couple of thousand miles I'll let you know how it feels then.
Bill
"serg" <none@none.com> wrote in message
news:rmUsc.57116$y%3.49430@newssvr29.news.prodigy. com...
> thanks for posting the results! i've been wondering about the power gains
> using a 4.0 head. i'm going to take mine in too when i'm finally done
with
> it.
>
> "William Oliveri" <wuji@bigvalley.net> wrote in message
> news:2hhg59Fd4rv0U1@uni-berlin.de...
> > 4.2 block / 4.0 Head.
> >
> > Results: 124.9 Horsepower. I should have about 160, yes?
> >
> > Air/Fuel ratio came back a tad lean if anything.
> >
> > Engine has about 60 miles on it.
> >
> > Mechanic told me there's nothing wrong with the injectors.
> >
> > Bill
> >
> >
>
>
#52
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
Well, let me just say this. At this time in my break in process, the my
BUTT Dyno sees little difference between the previous 4.2 and the current
setup.
After a couple of thousand miles I'll let you know how it feels then.
Bill
"serg" <none@none.com> wrote in message
news:rmUsc.57116$y%3.49430@newssvr29.news.prodigy. com...
> thanks for posting the results! i've been wondering about the power gains
> using a 4.0 head. i'm going to take mine in too when i'm finally done
with
> it.
>
> "William Oliveri" <wuji@bigvalley.net> wrote in message
> news:2hhg59Fd4rv0U1@uni-berlin.de...
> > 4.2 block / 4.0 Head.
> >
> > Results: 124.9 Horsepower. I should have about 160, yes?
> >
> > Air/Fuel ratio came back a tad lean if anything.
> >
> > Engine has about 60 miles on it.
> >
> > Mechanic told me there's nothing wrong with the injectors.
> >
> > Bill
> >
> >
>
>
BUTT Dyno sees little difference between the previous 4.2 and the current
setup.
After a couple of thousand miles I'll let you know how it feels then.
Bill
"serg" <none@none.com> wrote in message
news:rmUsc.57116$y%3.49430@newssvr29.news.prodigy. com...
> thanks for posting the results! i've been wondering about the power gains
> using a 4.0 head. i'm going to take mine in too when i'm finally done
with
> it.
>
> "William Oliveri" <wuji@bigvalley.net> wrote in message
> news:2hhg59Fd4rv0U1@uni-berlin.de...
> > 4.2 block / 4.0 Head.
> >
> > Results: 124.9 Horsepower. I should have about 160, yes?
> >
> > Air/Fuel ratio came back a tad lean if anything.
> >
> > Engine has about 60 miles on it.
> >
> > Mechanic told me there's nothing wrong with the injectors.
> >
> > Bill
> >
> >
>
>
#53
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
Well, let me just say this. At this time in my break in process, the my
BUTT Dyno sees little difference between the previous 4.2 and the current
setup.
After a couple of thousand miles I'll let you know how it feels then.
Bill
"serg" <none@none.com> wrote in message
news:rmUsc.57116$y%3.49430@newssvr29.news.prodigy. com...
> thanks for posting the results! i've been wondering about the power gains
> using a 4.0 head. i'm going to take mine in too when i'm finally done
with
> it.
>
> "William Oliveri" <wuji@bigvalley.net> wrote in message
> news:2hhg59Fd4rv0U1@uni-berlin.de...
> > 4.2 block / 4.0 Head.
> >
> > Results: 124.9 Horsepower. I should have about 160, yes?
> >
> > Air/Fuel ratio came back a tad lean if anything.
> >
> > Engine has about 60 miles on it.
> >
> > Mechanic told me there's nothing wrong with the injectors.
> >
> > Bill
> >
> >
>
>
BUTT Dyno sees little difference between the previous 4.2 and the current
setup.
After a couple of thousand miles I'll let you know how it feels then.
Bill
"serg" <none@none.com> wrote in message
news:rmUsc.57116$y%3.49430@newssvr29.news.prodigy. com...
> thanks for posting the results! i've been wondering about the power gains
> using a 4.0 head. i'm going to take mine in too when i'm finally done
with
> it.
>
> "William Oliveri" <wuji@bigvalley.net> wrote in message
> news:2hhg59Fd4rv0U1@uni-berlin.de...
> > 4.2 block / 4.0 Head.
> >
> > Results: 124.9 Horsepower. I should have about 160, yes?
> >
> > Air/Fuel ratio came back a tad lean if anything.
> >
> > Engine has about 60 miles on it.
> >
> > Mechanic told me there's nothing wrong with the injectors.
> >
> > Bill
> >
> >
>
>
#54
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
Someplace in there was a inner cooler from the parts picture.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
RocknTJ wrote:
>
> Oh yeah, some place in the post he tried bypassing the snorkel, using a
> conical K&N. There was a HP loss, a pre-detination (ping/knock) gain and an
> overall loss in performance.
>
> There is something to be said for the cool unrestricted air a snorkel on a
> TJ gives.
>
> --James
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
RocknTJ wrote:
>
> Oh yeah, some place in the post he tried bypassing the snorkel, using a
> conical K&N. There was a HP loss, a pre-detination (ping/knock) gain and an
> overall loss in performance.
>
> There is something to be said for the cool unrestricted air a snorkel on a
> TJ gives.
>
> --James
#55
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
Someplace in there was a inner cooler from the parts picture.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
RocknTJ wrote:
>
> Oh yeah, some place in the post he tried bypassing the snorkel, using a
> conical K&N. There was a HP loss, a pre-detination (ping/knock) gain and an
> overall loss in performance.
>
> There is something to be said for the cool unrestricted air a snorkel on a
> TJ gives.
>
> --James
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
RocknTJ wrote:
>
> Oh yeah, some place in the post he tried bypassing the snorkel, using a
> conical K&N. There was a HP loss, a pre-detination (ping/knock) gain and an
> overall loss in performance.
>
> There is something to be said for the cool unrestricted air a snorkel on a
> TJ gives.
>
> --James
#56
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
Someplace in there was a inner cooler from the parts picture.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
RocknTJ wrote:
>
> Oh yeah, some place in the post he tried bypassing the snorkel, using a
> conical K&N. There was a HP loss, a pre-detination (ping/knock) gain and an
> overall loss in performance.
>
> There is something to be said for the cool unrestricted air a snorkel on a
> TJ gives.
>
> --James
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
RocknTJ wrote:
>
> Oh yeah, some place in the post he tried bypassing the snorkel, using a
> conical K&N. There was a HP loss, a pre-detination (ping/knock) gain and an
> overall loss in performance.
>
> There is something to be said for the cool unrestricted air a snorkel on a
> TJ gives.
>
> --James
#57
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
Someplace in there was a inner cooler from the parts picture.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
RocknTJ wrote:
>
> Oh yeah, some place in the post he tried bypassing the snorkel, using a
> conical K&N. There was a HP loss, a pre-detination (ping/knock) gain and an
> overall loss in performance.
>
> There is something to be said for the cool unrestricted air a snorkel on a
> TJ gives.
>
> --James
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
RocknTJ wrote:
>
> Oh yeah, some place in the post he tried bypassing the snorkel, using a
> conical K&N. There was a HP loss, a pre-detination (ping/knock) gain and an
> overall loss in performance.
>
> There is something to be said for the cool unrestricted air a snorkel on a
> TJ gives.
>
> --James
#58
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
I would say so. And like I said in my previous post, I doubt he has reached
the power peak at 3300 RPM. It should be more like 4000 or so. Given all
that, Bill has a decent power output there considering he's apparently
running a bit lean, the engine is nowhere near broke in yet, and in all
honesty I would venture a guess that he may has more than a 20% loss through
the drivetrain being a 4wd. The bottom line either way is that it runs in a
way that makes him smile (especially given what he has gone through with
this project), and that it has enough power when he needs it.
Chris
"serg" <none@none.com> wrote in message
news:GgUsc.57115$FY3.33698@newssvr29.news.prodigy. com...
> so if we assume a 20% loss at the drivetrain...his HP comes out to be...
> 124.9/.8=156.13 HP
> close enough to 160 HP right?
>
> "c" <c@me.org> wrote in message
> news:jUMsc.21102$zn.19115@twister.rdc-kc.rr.com...
> > Bill,
> >
> > They probably didn't get the engine to its peak power RPM. Remember, the
> 4.0
> > head makes peak power at about 4000 RPM. The head doesn't know what
engine
> > it is sitting on top of. If the engines are approximately the same size,
> the
> > bore and stroke don't have much effect on the peak power RPM. A long
> stroke,
> > small bore engine should make more low RPM torque than a short stroke,
big
> > bore engine. Also, porting a head will almost always move the power band
> up.
> >
> > To explain this to some degree, a cylinder head port by design has a
> "sweet
> > spot" where it best fills and empties the cylinder. This is basically
> where
> > your power peak will be. This also works in conjustion with the intake,
> > camshaft and exhaust. This is why it is important to match all of the
> > components so that they all, by design, produce their peak power at
about
> > the same RPM. In your case, the head is probably helping a little in the
> > lower RPM and will show more improvement as the RPM gets closer to 4000.
> >
> > As far as the dyno test, if they used a chassis dyno and read the power
at
> > the rear wheels, then it is rear wheel horsepower. This number is
> generally
> > about 20-30% lower than the flywheel rating due to friction losses in
the
> > trans, transfer case, and axle. An automatic trans will usually show
more
> > power loss than a standard because of the toque convertor and more
> friction
> > loss internally.
> >
> > Did they give you a copy of the dyno sheet? If so, look at the number in
> the
> > BSFC (Brake specific fuel comsumption) column. This will give a good
idea
> as
> > to where the fuel mixture is. The number should be around 0.5 or a bit
> > higher for the correct fuel mixture. This basically means that it is
using
> > .5 pounds of fuel per horsepower per hour. If the number is too high, it
> > shows an inefficient engine. This would have also been a good time for
you
> > to play with your timing to optimize it. Normally, the timing that shows
> the
> > best power on the dyno will be 2-4 degrees higher than what you should
run
> > because of temperature, barometric pressure, and load changes in real
> world
> > driving.
> >
> > Chris
> >
> > "William Oliveri" <wuji@bigvalley.net> wrote in message
> > news:2hhi42Fco2thU1@uni-berlin.de...
> > > The 4.2/4.0 mod should add about 40 horse power due to the porting on
> the
> > > 4.0L head.
> > >
> > > I'm not sure how the dyno test works but I think it's at the wheels.
> > >
> > > Looks like they cut it off at about 3350 rpm.
> > >
> > > Bill
> > >
> > >
> > >
> > > "Tim Vice" <timothy.vice@washburn.edu> wrote in message
> > > news:36Msc.67492$iy5.64474@okepread05...
> > > > Is the horsepower that you are getting at the wheels, or at the
crank?
> > > >
> > > > What is the difference in the heads to create more horsepower, or
have
> > you
> > > > done some other things?
> > > >
> > > > At what RPM was the highest horsepower created?
> > > >
> > > > Just some questions because I'm looking into stroking my 4.0
> > > >
> > > > Tim
> > > >
> > > >
> > > > "William Oliveri" <wuji@bigvalley.net> wrote in message
> > > > news:2hhg59Fd4rv0U1@uni-berlin.de...
> > > > > 4.2 block / 4.0 Head.
> > > > >
> > > > > Results: 124.9 Horsepower. I should have about 160, yes?
> > > > >
> > > > > Air/Fuel ratio came back a tad lean if anything.
> > > > >
> > > > > Engine has about 60 miles on it.
> > > > >
> > > > > Mechanic told me there's nothing wrong with the injectors.
> > > > >
> > > > > Bill
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
the power peak at 3300 RPM. It should be more like 4000 or so. Given all
that, Bill has a decent power output there considering he's apparently
running a bit lean, the engine is nowhere near broke in yet, and in all
honesty I would venture a guess that he may has more than a 20% loss through
the drivetrain being a 4wd. The bottom line either way is that it runs in a
way that makes him smile (especially given what he has gone through with
this project), and that it has enough power when he needs it.
Chris
"serg" <none@none.com> wrote in message
news:GgUsc.57115$FY3.33698@newssvr29.news.prodigy. com...
> so if we assume a 20% loss at the drivetrain...his HP comes out to be...
> 124.9/.8=156.13 HP
> close enough to 160 HP right?
>
> "c" <c@me.org> wrote in message
> news:jUMsc.21102$zn.19115@twister.rdc-kc.rr.com...
> > Bill,
> >
> > They probably didn't get the engine to its peak power RPM. Remember, the
> 4.0
> > head makes peak power at about 4000 RPM. The head doesn't know what
engine
> > it is sitting on top of. If the engines are approximately the same size,
> the
> > bore and stroke don't have much effect on the peak power RPM. A long
> stroke,
> > small bore engine should make more low RPM torque than a short stroke,
big
> > bore engine. Also, porting a head will almost always move the power band
> up.
> >
> > To explain this to some degree, a cylinder head port by design has a
> "sweet
> > spot" where it best fills and empties the cylinder. This is basically
> where
> > your power peak will be. This also works in conjustion with the intake,
> > camshaft and exhaust. This is why it is important to match all of the
> > components so that they all, by design, produce their peak power at
about
> > the same RPM. In your case, the head is probably helping a little in the
> > lower RPM and will show more improvement as the RPM gets closer to 4000.
> >
> > As far as the dyno test, if they used a chassis dyno and read the power
at
> > the rear wheels, then it is rear wheel horsepower. This number is
> generally
> > about 20-30% lower than the flywheel rating due to friction losses in
the
> > trans, transfer case, and axle. An automatic trans will usually show
more
> > power loss than a standard because of the toque convertor and more
> friction
> > loss internally.
> >
> > Did they give you a copy of the dyno sheet? If so, look at the number in
> the
> > BSFC (Brake specific fuel comsumption) column. This will give a good
idea
> as
> > to where the fuel mixture is. The number should be around 0.5 or a bit
> > higher for the correct fuel mixture. This basically means that it is
using
> > .5 pounds of fuel per horsepower per hour. If the number is too high, it
> > shows an inefficient engine. This would have also been a good time for
you
> > to play with your timing to optimize it. Normally, the timing that shows
> the
> > best power on the dyno will be 2-4 degrees higher than what you should
run
> > because of temperature, barometric pressure, and load changes in real
> world
> > driving.
> >
> > Chris
> >
> > "William Oliveri" <wuji@bigvalley.net> wrote in message
> > news:2hhi42Fco2thU1@uni-berlin.de...
> > > The 4.2/4.0 mod should add about 40 horse power due to the porting on
> the
> > > 4.0L head.
> > >
> > > I'm not sure how the dyno test works but I think it's at the wheels.
> > >
> > > Looks like they cut it off at about 3350 rpm.
> > >
> > > Bill
> > >
> > >
> > >
> > > "Tim Vice" <timothy.vice@washburn.edu> wrote in message
> > > news:36Msc.67492$iy5.64474@okepread05...
> > > > Is the horsepower that you are getting at the wheels, or at the
crank?
> > > >
> > > > What is the difference in the heads to create more horsepower, or
have
> > you
> > > > done some other things?
> > > >
> > > > At what RPM was the highest horsepower created?
> > > >
> > > > Just some questions because I'm looking into stroking my 4.0
> > > >
> > > > Tim
> > > >
> > > >
> > > > "William Oliveri" <wuji@bigvalley.net> wrote in message
> > > > news:2hhg59Fd4rv0U1@uni-berlin.de...
> > > > > 4.2 block / 4.0 Head.
> > > > >
> > > > > Results: 124.9 Horsepower. I should have about 160, yes?
> > > > >
> > > > > Air/Fuel ratio came back a tad lean if anything.
> > > > >
> > > > > Engine has about 60 miles on it.
> > > > >
> > > > > Mechanic told me there's nothing wrong with the injectors.
> > > > >
> > > > > Bill
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
#59
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
I would say so. And like I said in my previous post, I doubt he has reached
the power peak at 3300 RPM. It should be more like 4000 or so. Given all
that, Bill has a decent power output there considering he's apparently
running a bit lean, the engine is nowhere near broke in yet, and in all
honesty I would venture a guess that he may has more than a 20% loss through
the drivetrain being a 4wd. The bottom line either way is that it runs in a
way that makes him smile (especially given what he has gone through with
this project), and that it has enough power when he needs it.
Chris
"serg" <none@none.com> wrote in message
news:GgUsc.57115$FY3.33698@newssvr29.news.prodigy. com...
> so if we assume a 20% loss at the drivetrain...his HP comes out to be...
> 124.9/.8=156.13 HP
> close enough to 160 HP right?
>
> "c" <c@me.org> wrote in message
> news:jUMsc.21102$zn.19115@twister.rdc-kc.rr.com...
> > Bill,
> >
> > They probably didn't get the engine to its peak power RPM. Remember, the
> 4.0
> > head makes peak power at about 4000 RPM. The head doesn't know what
engine
> > it is sitting on top of. If the engines are approximately the same size,
> the
> > bore and stroke don't have much effect on the peak power RPM. A long
> stroke,
> > small bore engine should make more low RPM torque than a short stroke,
big
> > bore engine. Also, porting a head will almost always move the power band
> up.
> >
> > To explain this to some degree, a cylinder head port by design has a
> "sweet
> > spot" where it best fills and empties the cylinder. This is basically
> where
> > your power peak will be. This also works in conjustion with the intake,
> > camshaft and exhaust. This is why it is important to match all of the
> > components so that they all, by design, produce their peak power at
about
> > the same RPM. In your case, the head is probably helping a little in the
> > lower RPM and will show more improvement as the RPM gets closer to 4000.
> >
> > As far as the dyno test, if they used a chassis dyno and read the power
at
> > the rear wheels, then it is rear wheel horsepower. This number is
> generally
> > about 20-30% lower than the flywheel rating due to friction losses in
the
> > trans, transfer case, and axle. An automatic trans will usually show
more
> > power loss than a standard because of the toque convertor and more
> friction
> > loss internally.
> >
> > Did they give you a copy of the dyno sheet? If so, look at the number in
> the
> > BSFC (Brake specific fuel comsumption) column. This will give a good
idea
> as
> > to where the fuel mixture is. The number should be around 0.5 or a bit
> > higher for the correct fuel mixture. This basically means that it is
using
> > .5 pounds of fuel per horsepower per hour. If the number is too high, it
> > shows an inefficient engine. This would have also been a good time for
you
> > to play with your timing to optimize it. Normally, the timing that shows
> the
> > best power on the dyno will be 2-4 degrees higher than what you should
run
> > because of temperature, barometric pressure, and load changes in real
> world
> > driving.
> >
> > Chris
> >
> > "William Oliveri" <wuji@bigvalley.net> wrote in message
> > news:2hhi42Fco2thU1@uni-berlin.de...
> > > The 4.2/4.0 mod should add about 40 horse power due to the porting on
> the
> > > 4.0L head.
> > >
> > > I'm not sure how the dyno test works but I think it's at the wheels.
> > >
> > > Looks like they cut it off at about 3350 rpm.
> > >
> > > Bill
> > >
> > >
> > >
> > > "Tim Vice" <timothy.vice@washburn.edu> wrote in message
> > > news:36Msc.67492$iy5.64474@okepread05...
> > > > Is the horsepower that you are getting at the wheels, or at the
crank?
> > > >
> > > > What is the difference in the heads to create more horsepower, or
have
> > you
> > > > done some other things?
> > > >
> > > > At what RPM was the highest horsepower created?
> > > >
> > > > Just some questions because I'm looking into stroking my 4.0
> > > >
> > > > Tim
> > > >
> > > >
> > > > "William Oliveri" <wuji@bigvalley.net> wrote in message
> > > > news:2hhg59Fd4rv0U1@uni-berlin.de...
> > > > > 4.2 block / 4.0 Head.
> > > > >
> > > > > Results: 124.9 Horsepower. I should have about 160, yes?
> > > > >
> > > > > Air/Fuel ratio came back a tad lean if anything.
> > > > >
> > > > > Engine has about 60 miles on it.
> > > > >
> > > > > Mechanic told me there's nothing wrong with the injectors.
> > > > >
> > > > > Bill
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
the power peak at 3300 RPM. It should be more like 4000 or so. Given all
that, Bill has a decent power output there considering he's apparently
running a bit lean, the engine is nowhere near broke in yet, and in all
honesty I would venture a guess that he may has more than a 20% loss through
the drivetrain being a 4wd. The bottom line either way is that it runs in a
way that makes him smile (especially given what he has gone through with
this project), and that it has enough power when he needs it.
Chris
"serg" <none@none.com> wrote in message
news:GgUsc.57115$FY3.33698@newssvr29.news.prodigy. com...
> so if we assume a 20% loss at the drivetrain...his HP comes out to be...
> 124.9/.8=156.13 HP
> close enough to 160 HP right?
>
> "c" <c@me.org> wrote in message
> news:jUMsc.21102$zn.19115@twister.rdc-kc.rr.com...
> > Bill,
> >
> > They probably didn't get the engine to its peak power RPM. Remember, the
> 4.0
> > head makes peak power at about 4000 RPM. The head doesn't know what
engine
> > it is sitting on top of. If the engines are approximately the same size,
> the
> > bore and stroke don't have much effect on the peak power RPM. A long
> stroke,
> > small bore engine should make more low RPM torque than a short stroke,
big
> > bore engine. Also, porting a head will almost always move the power band
> up.
> >
> > To explain this to some degree, a cylinder head port by design has a
> "sweet
> > spot" where it best fills and empties the cylinder. This is basically
> where
> > your power peak will be. This also works in conjustion with the intake,
> > camshaft and exhaust. This is why it is important to match all of the
> > components so that they all, by design, produce their peak power at
about
> > the same RPM. In your case, the head is probably helping a little in the
> > lower RPM and will show more improvement as the RPM gets closer to 4000.
> >
> > As far as the dyno test, if they used a chassis dyno and read the power
at
> > the rear wheels, then it is rear wheel horsepower. This number is
> generally
> > about 20-30% lower than the flywheel rating due to friction losses in
the
> > trans, transfer case, and axle. An automatic trans will usually show
more
> > power loss than a standard because of the toque convertor and more
> friction
> > loss internally.
> >
> > Did they give you a copy of the dyno sheet? If so, look at the number in
> the
> > BSFC (Brake specific fuel comsumption) column. This will give a good
idea
> as
> > to where the fuel mixture is. The number should be around 0.5 or a bit
> > higher for the correct fuel mixture. This basically means that it is
using
> > .5 pounds of fuel per horsepower per hour. If the number is too high, it
> > shows an inefficient engine. This would have also been a good time for
you
> > to play with your timing to optimize it. Normally, the timing that shows
> the
> > best power on the dyno will be 2-4 degrees higher than what you should
run
> > because of temperature, barometric pressure, and load changes in real
> world
> > driving.
> >
> > Chris
> >
> > "William Oliveri" <wuji@bigvalley.net> wrote in message
> > news:2hhi42Fco2thU1@uni-berlin.de...
> > > The 4.2/4.0 mod should add about 40 horse power due to the porting on
> the
> > > 4.0L head.
> > >
> > > I'm not sure how the dyno test works but I think it's at the wheels.
> > >
> > > Looks like they cut it off at about 3350 rpm.
> > >
> > > Bill
> > >
> > >
> > >
> > > "Tim Vice" <timothy.vice@washburn.edu> wrote in message
> > > news:36Msc.67492$iy5.64474@okepread05...
> > > > Is the horsepower that you are getting at the wheels, or at the
crank?
> > > >
> > > > What is the difference in the heads to create more horsepower, or
have
> > you
> > > > done some other things?
> > > >
> > > > At what RPM was the highest horsepower created?
> > > >
> > > > Just some questions because I'm looking into stroking my 4.0
> > > >
> > > > Tim
> > > >
> > > >
> > > > "William Oliveri" <wuji@bigvalley.net> wrote in message
> > > > news:2hhg59Fd4rv0U1@uni-berlin.de...
> > > > > 4.2 block / 4.0 Head.
> > > > >
> > > > > Results: 124.9 Horsepower. I should have about 160, yes?
> > > > >
> > > > > Air/Fuel ratio came back a tad lean if anything.
> > > > >
> > > > > Engine has about 60 miles on it.
> > > > >
> > > > > Mechanic told me there's nothing wrong with the injectors.
> > > > >
> > > > > Bill
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
#60
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
I would say so. And like I said in my previous post, I doubt he has reached
the power peak at 3300 RPM. It should be more like 4000 or so. Given all
that, Bill has a decent power output there considering he's apparently
running a bit lean, the engine is nowhere near broke in yet, and in all
honesty I would venture a guess that he may has more than a 20% loss through
the drivetrain being a 4wd. The bottom line either way is that it runs in a
way that makes him smile (especially given what he has gone through with
this project), and that it has enough power when he needs it.
Chris
"serg" <none@none.com> wrote in message
news:GgUsc.57115$FY3.33698@newssvr29.news.prodigy. com...
> so if we assume a 20% loss at the drivetrain...his HP comes out to be...
> 124.9/.8=156.13 HP
> close enough to 160 HP right?
>
> "c" <c@me.org> wrote in message
> news:jUMsc.21102$zn.19115@twister.rdc-kc.rr.com...
> > Bill,
> >
> > They probably didn't get the engine to its peak power RPM. Remember, the
> 4.0
> > head makes peak power at about 4000 RPM. The head doesn't know what
engine
> > it is sitting on top of. If the engines are approximately the same size,
> the
> > bore and stroke don't have much effect on the peak power RPM. A long
> stroke,
> > small bore engine should make more low RPM torque than a short stroke,
big
> > bore engine. Also, porting a head will almost always move the power band
> up.
> >
> > To explain this to some degree, a cylinder head port by design has a
> "sweet
> > spot" where it best fills and empties the cylinder. This is basically
> where
> > your power peak will be. This also works in conjustion with the intake,
> > camshaft and exhaust. This is why it is important to match all of the
> > components so that they all, by design, produce their peak power at
about
> > the same RPM. In your case, the head is probably helping a little in the
> > lower RPM and will show more improvement as the RPM gets closer to 4000.
> >
> > As far as the dyno test, if they used a chassis dyno and read the power
at
> > the rear wheels, then it is rear wheel horsepower. This number is
> generally
> > about 20-30% lower than the flywheel rating due to friction losses in
the
> > trans, transfer case, and axle. An automatic trans will usually show
more
> > power loss than a standard because of the toque convertor and more
> friction
> > loss internally.
> >
> > Did they give you a copy of the dyno sheet? If so, look at the number in
> the
> > BSFC (Brake specific fuel comsumption) column. This will give a good
idea
> as
> > to where the fuel mixture is. The number should be around 0.5 or a bit
> > higher for the correct fuel mixture. This basically means that it is
using
> > .5 pounds of fuel per horsepower per hour. If the number is too high, it
> > shows an inefficient engine. This would have also been a good time for
you
> > to play with your timing to optimize it. Normally, the timing that shows
> the
> > best power on the dyno will be 2-4 degrees higher than what you should
run
> > because of temperature, barometric pressure, and load changes in real
> world
> > driving.
> >
> > Chris
> >
> > "William Oliveri" <wuji@bigvalley.net> wrote in message
> > news:2hhi42Fco2thU1@uni-berlin.de...
> > > The 4.2/4.0 mod should add about 40 horse power due to the porting on
> the
> > > 4.0L head.
> > >
> > > I'm not sure how the dyno test works but I think it's at the wheels.
> > >
> > > Looks like they cut it off at about 3350 rpm.
> > >
> > > Bill
> > >
> > >
> > >
> > > "Tim Vice" <timothy.vice@washburn.edu> wrote in message
> > > news:36Msc.67492$iy5.64474@okepread05...
> > > > Is the horsepower that you are getting at the wheels, or at the
crank?
> > > >
> > > > What is the difference in the heads to create more horsepower, or
have
> > you
> > > > done some other things?
> > > >
> > > > At what RPM was the highest horsepower created?
> > > >
> > > > Just some questions because I'm looking into stroking my 4.0
> > > >
> > > > Tim
> > > >
> > > >
> > > > "William Oliveri" <wuji@bigvalley.net> wrote in message
> > > > news:2hhg59Fd4rv0U1@uni-berlin.de...
> > > > > 4.2 block / 4.0 Head.
> > > > >
> > > > > Results: 124.9 Horsepower. I should have about 160, yes?
> > > > >
> > > > > Air/Fuel ratio came back a tad lean if anything.
> > > > >
> > > > > Engine has about 60 miles on it.
> > > > >
> > > > > Mechanic told me there's nothing wrong with the injectors.
> > > > >
> > > > > Bill
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
the power peak at 3300 RPM. It should be more like 4000 or so. Given all
that, Bill has a decent power output there considering he's apparently
running a bit lean, the engine is nowhere near broke in yet, and in all
honesty I would venture a guess that he may has more than a 20% loss through
the drivetrain being a 4wd. The bottom line either way is that it runs in a
way that makes him smile (especially given what he has gone through with
this project), and that it has enough power when he needs it.
Chris
"serg" <none@none.com> wrote in message
news:GgUsc.57115$FY3.33698@newssvr29.news.prodigy. com...
> so if we assume a 20% loss at the drivetrain...his HP comes out to be...
> 124.9/.8=156.13 HP
> close enough to 160 HP right?
>
> "c" <c@me.org> wrote in message
> news:jUMsc.21102$zn.19115@twister.rdc-kc.rr.com...
> > Bill,
> >
> > They probably didn't get the engine to its peak power RPM. Remember, the
> 4.0
> > head makes peak power at about 4000 RPM. The head doesn't know what
engine
> > it is sitting on top of. If the engines are approximately the same size,
> the
> > bore and stroke don't have much effect on the peak power RPM. A long
> stroke,
> > small bore engine should make more low RPM torque than a short stroke,
big
> > bore engine. Also, porting a head will almost always move the power band
> up.
> >
> > To explain this to some degree, a cylinder head port by design has a
> "sweet
> > spot" where it best fills and empties the cylinder. This is basically
> where
> > your power peak will be. This also works in conjustion with the intake,
> > camshaft and exhaust. This is why it is important to match all of the
> > components so that they all, by design, produce their peak power at
about
> > the same RPM. In your case, the head is probably helping a little in the
> > lower RPM and will show more improvement as the RPM gets closer to 4000.
> >
> > As far as the dyno test, if they used a chassis dyno and read the power
at
> > the rear wheels, then it is rear wheel horsepower. This number is
> generally
> > about 20-30% lower than the flywheel rating due to friction losses in
the
> > trans, transfer case, and axle. An automatic trans will usually show
more
> > power loss than a standard because of the toque convertor and more
> friction
> > loss internally.
> >
> > Did they give you a copy of the dyno sheet? If so, look at the number in
> the
> > BSFC (Brake specific fuel comsumption) column. This will give a good
idea
> as
> > to where the fuel mixture is. The number should be around 0.5 or a bit
> > higher for the correct fuel mixture. This basically means that it is
using
> > .5 pounds of fuel per horsepower per hour. If the number is too high, it
> > shows an inefficient engine. This would have also been a good time for
you
> > to play with your timing to optimize it. Normally, the timing that shows
> the
> > best power on the dyno will be 2-4 degrees higher than what you should
run
> > because of temperature, barometric pressure, and load changes in real
> world
> > driving.
> >
> > Chris
> >
> > "William Oliveri" <wuji@bigvalley.net> wrote in message
> > news:2hhi42Fco2thU1@uni-berlin.de...
> > > The 4.2/4.0 mod should add about 40 horse power due to the porting on
> the
> > > 4.0L head.
> > >
> > > I'm not sure how the dyno test works but I think it's at the wheels.
> > >
> > > Looks like they cut it off at about 3350 rpm.
> > >
> > > Bill
> > >
> > >
> > >
> > > "Tim Vice" <timothy.vice@washburn.edu> wrote in message
> > > news:36Msc.67492$iy5.64474@okepread05...
> > > > Is the horsepower that you are getting at the wheels, or at the
crank?
> > > >
> > > > What is the difference in the heads to create more horsepower, or
have
> > you
> > > > done some other things?
> > > >
> > > > At what RPM was the highest horsepower created?
> > > >
> > > > Just some questions because I'm looking into stroking my 4.0
> > > >
> > > > Tim
> > > >
> > > >
> > > > "William Oliveri" <wuji@bigvalley.net> wrote in message
> > > > news:2hhg59Fd4rv0U1@uni-berlin.de...
> > > > > 4.2 block / 4.0 Head.
> > > > >
> > > > > Results: 124.9 Horsepower. I should have about 160, yes?
> > > > >
> > > > > Air/Fuel ratio came back a tad lean if anything.
> > > > >
> > > > > Engine has about 60 miles on it.
> > > > >
> > > > > Mechanic told me there's nothing wrong with the injectors.
> > > > >
> > > > > Bill
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>