Just had my engine dyno'd and air fuel ratio checked
Guest
Posts: n/a
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
> >
> >
>
>
Guest
Posts: n/a
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
> >
> >
>
>
Guest
Posts: n/a
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
> >
> >
>
>
Guest
Posts: n/a
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
Guest
Posts: n/a
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
Guest
Posts: n/a
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
Guest
Posts: n/a
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
Guest
Posts: n/a
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
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
Guest
Posts: n/a
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
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
Guest
Posts: n/a
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
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>


