Just had my engine dyno'd and air fuel ratio checked
05-26-2004, 12:58 AM
#61
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
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
05-26-2004, 01:21 AM
#62
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
You are correct Chris. The Dyno tester said he didn't want to run it full
throttle or as he would a already broken in engine.
The main purpose for this test was the Air/Fuel ratio test, not the Dyno.
Why they needed to do the dyno I don't know. Especially since it's a new
engine.
I have yet to get my smile on this one. Seems like the damn thing ran
better with one cylinder sucking oil. I'm taking it to the Jeep Doctor
(JeepsRUs) when I can get in which appears to be next weekend (after the
holiday).
The engine seem has this kind of humming/buzzing vibration at idle which
goes for a while, lets up, and goes again.
What would happen if the balanced Flywheel and Clutch plate were not
aligned. Would that be enough cause a vibration? I've had the timing off
before and it didn't feel like that.
Sheeezzzhh...
Bill
"c" <c@me.org> wrote in message
news:3uVsc.21192$zn.3953@twister.rdc-kc.rr.com...
> I would say so. And like I said in my previous post, I doubt he has
reached
> the power peak at 3300 RPM. It should be more like 4000 or so. Given all
> that, Bill has a decent power output there considering he's apparently
> running a bit lean, the engine is nowhere near broke in yet, and in all
> honesty I would venture a guess that he may has more than a 20% loss
through
> the drivetrain being a 4wd. The bottom line either way is that it runs in
a
> way that makes him smile (especially given what he has gone through with
> this project), and that it has enough power when he needs it.
>
> Chris
>
> "serg" <none@none.com> wrote in message
> news:GgUsc.57115$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
> > > > > >
> > > > > >
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
throttle or as he would a already broken in engine.
The main purpose for this test was the Air/Fuel ratio test, not the Dyno.
Why they needed to do the dyno I don't know. Especially since it's a new
engine.
I have yet to get my smile on this one. Seems like the damn thing ran
better with one cylinder sucking oil. I'm taking it to the Jeep Doctor
(JeepsRUs) when I can get in which appears to be next weekend (after the
holiday).
The engine seem has this kind of humming/buzzing vibration at idle which
goes for a while, lets up, and goes again.
What would happen if the balanced Flywheel and Clutch plate were not
aligned. Would that be enough cause a vibration? I've had the timing off
before and it didn't feel like that.
Sheeezzzhh...
Bill
"c" <c@me.org> wrote in message
news:3uVsc.21192$zn.3953@twister.rdc-kc.rr.com...
> I would say so. And like I said in my previous post, I doubt he has
reached
> the power peak at 3300 RPM. It should be more like 4000 or so. Given all
> that, Bill has a decent power output there considering he's apparently
> running a bit lean, the engine is nowhere near broke in yet, and in all
> honesty I would venture a guess that he may has more than a 20% loss
through
> the drivetrain being a 4wd. The bottom line either way is that it runs in
a
> way that makes him smile (especially given what he has gone through with
> this project), and that it has enough power when he needs it.
>
> Chris
>
> "serg" <none@none.com> wrote in message
> news:GgUsc.57115$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
> > > > > >
> > > > > >
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
05-26-2004, 01:21 AM
#63
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
You are correct Chris. The Dyno tester said he didn't want to run it full
throttle or as he would a already broken in engine.
The main purpose for this test was the Air/Fuel ratio test, not the Dyno.
Why they needed to do the dyno I don't know. Especially since it's a new
engine.
I have yet to get my smile on this one. Seems like the damn thing ran
better with one cylinder sucking oil. I'm taking it to the Jeep Doctor
(JeepsRUs) when I can get in which appears to be next weekend (after the
holiday).
The engine seem has this kind of humming/buzzing vibration at idle which
goes for a while, lets up, and goes again.
What would happen if the balanced Flywheel and Clutch plate were not
aligned. Would that be enough cause a vibration? I've had the timing off
before and it didn't feel like that.
Sheeezzzhh...
Bill
"c" <c@me.org> wrote in message
news:3uVsc.21192$zn.3953@twister.rdc-kc.rr.com...
> I would say so. And like I said in my previous post, I doubt he has
reached
> the power peak at 3300 RPM. It should be more like 4000 or so. Given all
> that, Bill has a decent power output there considering he's apparently
> running a bit lean, the engine is nowhere near broke in yet, and in all
> honesty I would venture a guess that he may has more than a 20% loss
through
> the drivetrain being a 4wd. The bottom line either way is that it runs in
a
> way that makes him smile (especially given what he has gone through with
> this project), and that it has enough power when he needs it.
>
> Chris
>
> "serg" <none@none.com> wrote in message
> news:GgUsc.57115$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
> > > > > >
> > > > > >
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
throttle or as he would a already broken in engine.
The main purpose for this test was the Air/Fuel ratio test, not the Dyno.
Why they needed to do the dyno I don't know. Especially since it's a new
engine.
I have yet to get my smile on this one. Seems like the damn thing ran
better with one cylinder sucking oil. I'm taking it to the Jeep Doctor
(JeepsRUs) when I can get in which appears to be next weekend (after the
holiday).
The engine seem has this kind of humming/buzzing vibration at idle which
goes for a while, lets up, and goes again.
What would happen if the balanced Flywheel and Clutch plate were not
aligned. Would that be enough cause a vibration? I've had the timing off
before and it didn't feel like that.
Sheeezzzhh...
Bill
"c" <c@me.org> wrote in message
news:3uVsc.21192$zn.3953@twister.rdc-kc.rr.com...
> I would say so. And like I said in my previous post, I doubt he has
reached
> the power peak at 3300 RPM. It should be more like 4000 or so. Given all
> that, Bill has a decent power output there considering he's apparently
> running a bit lean, the engine is nowhere near broke in yet, and in all
> honesty I would venture a guess that he may has more than a 20% loss
through
> the drivetrain being a 4wd. The bottom line either way is that it runs in
a
> way that makes him smile (especially given what he has gone through with
> this project), and that it has enough power when he needs it.
>
> Chris
>
> "serg" <none@none.com> wrote in message
> news:GgUsc.57115$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
> > > > > >
> > > > > >
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
05-26-2004, 01:21 AM
#64
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
You are correct Chris. The Dyno tester said he didn't want to run it full
throttle or as he would a already broken in engine.
The main purpose for this test was the Air/Fuel ratio test, not the Dyno.
Why they needed to do the dyno I don't know. Especially since it's a new
engine.
I have yet to get my smile on this one. Seems like the damn thing ran
better with one cylinder sucking oil. I'm taking it to the Jeep Doctor
(JeepsRUs) when I can get in which appears to be next weekend (after the
holiday).
The engine seem has this kind of humming/buzzing vibration at idle which
goes for a while, lets up, and goes again.
What would happen if the balanced Flywheel and Clutch plate were not
aligned. Would that be enough cause a vibration? I've had the timing off
before and it didn't feel like that.
Sheeezzzhh...
Bill
"c" <c@me.org> wrote in message
news:3uVsc.21192$zn.3953@twister.rdc-kc.rr.com...
> I would say so. And like I said in my previous post, I doubt he has
reached
> the power peak at 3300 RPM. It should be more like 4000 or so. Given all
> that, Bill has a decent power output there considering he's apparently
> running a bit lean, the engine is nowhere near broke in yet, and in all
> honesty I would venture a guess that he may has more than a 20% loss
through
> the drivetrain being a 4wd. The bottom line either way is that it runs in
a
> way that makes him smile (especially given what he has gone through with
> this project), and that it has enough power when he needs it.
>
> Chris
>
> "serg" <none@none.com> wrote in message
> news:GgUsc.57115$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
> > > > > >
> > > > > >
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
throttle or as he would a already broken in engine.
The main purpose for this test was the Air/Fuel ratio test, not the Dyno.
Why they needed to do the dyno I don't know. Especially since it's a new
engine.
I have yet to get my smile on this one. Seems like the damn thing ran
better with one cylinder sucking oil. I'm taking it to the Jeep Doctor
(JeepsRUs) when I can get in which appears to be next weekend (after the
holiday).
The engine seem has this kind of humming/buzzing vibration at idle which
goes for a while, lets up, and goes again.
What would happen if the balanced Flywheel and Clutch plate were not
aligned. Would that be enough cause a vibration? I've had the timing off
before and it didn't feel like that.
Sheeezzzhh...
Bill
"c" <c@me.org> wrote in message
news:3uVsc.21192$zn.3953@twister.rdc-kc.rr.com...
> I would say so. And like I said in my previous post, I doubt he has
reached
> the power peak at 3300 RPM. It should be more like 4000 or so. Given all
> that, Bill has a decent power output there considering he's apparently
> running a bit lean, the engine is nowhere near broke in yet, and in all
> honesty I would venture a guess that he may has more than a 20% loss
through
> the drivetrain being a 4wd. The bottom line either way is that it runs in
a
> way that makes him smile (especially given what he has gone through with
> this project), and that it has enough power when he needs it.
>
> Chris
>
> "serg" <none@none.com> wrote in message
> news:GgUsc.57115$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
> > > > > >
> > > > > >
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
05-26-2004, 01:21 AM
#65
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
You are correct Chris. The Dyno tester said he didn't want to run it full
throttle or as he would a already broken in engine.
The main purpose for this test was the Air/Fuel ratio test, not the Dyno.
Why they needed to do the dyno I don't know. Especially since it's a new
engine.
I have yet to get my smile on this one. Seems like the damn thing ran
better with one cylinder sucking oil. I'm taking it to the Jeep Doctor
(JeepsRUs) when I can get in which appears to be next weekend (after the
holiday).
The engine seem has this kind of humming/buzzing vibration at idle which
goes for a while, lets up, and goes again.
What would happen if the balanced Flywheel and Clutch plate were not
aligned. Would that be enough cause a vibration? I've had the timing off
before and it didn't feel like that.
Sheeezzzhh...
Bill
"c" <c@me.org> wrote in message
news:3uVsc.21192$zn.3953@twister.rdc-kc.rr.com...
> I would say so. And like I said in my previous post, I doubt he has
reached
> the power peak at 3300 RPM. It should be more like 4000 or so. Given all
> that, Bill has a decent power output there considering he's apparently
> running a bit lean, the engine is nowhere near broke in yet, and in all
> honesty I would venture a guess that he may has more than a 20% loss
through
> the drivetrain being a 4wd. The bottom line either way is that it runs in
a
> way that makes him smile (especially given what he has gone through with
> this project), and that it has enough power when he needs it.
>
> Chris
>
> "serg" <none@none.com> wrote in message
> news:GgUsc.57115$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
> > > > > >
> > > > > >
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
throttle or as he would a already broken in engine.
The main purpose for this test was the Air/Fuel ratio test, not the Dyno.
Why they needed to do the dyno I don't know. Especially since it's a new
engine.
I have yet to get my smile on this one. Seems like the damn thing ran
better with one cylinder sucking oil. I'm taking it to the Jeep Doctor
(JeepsRUs) when I can get in which appears to be next weekend (after the
holiday).
The engine seem has this kind of humming/buzzing vibration at idle which
goes for a while, lets up, and goes again.
What would happen if the balanced Flywheel and Clutch plate were not
aligned. Would that be enough cause a vibration? I've had the timing off
before and it didn't feel like that.
Sheeezzzhh...
Bill
"c" <c@me.org> wrote in message
news:3uVsc.21192$zn.3953@twister.rdc-kc.rr.com...
> I would say so. And like I said in my previous post, I doubt he has
reached
> the power peak at 3300 RPM. It should be more like 4000 or so. Given all
> that, Bill has a decent power output there considering he's apparently
> running a bit lean, the engine is nowhere near broke in yet, and in all
> honesty I would venture a guess that he may has more than a 20% loss
through
> the drivetrain being a 4wd. The bottom line either way is that it runs in
a
> way that makes him smile (especially given what he has gone through with
> this project), and that it has enough power when he needs it.
>
> Chris
>
> "serg" <none@none.com> wrote in message
> news:GgUsc.57115$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
> > > > > >
> > > > > >
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>
05-26-2004, 01:23 AM
#66
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
Agreed.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
c wrote:
>
> 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
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
c wrote:
>
> 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
05-26-2004, 01:23 AM
#67
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
Agreed.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
c wrote:
>
> 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
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
c wrote:
>
> 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
05-26-2004, 01:23 AM
#68
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
Agreed.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
c wrote:
>
> 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
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
c wrote:
>
> 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
05-26-2004, 01:23 AM
#69
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
Agreed.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
c wrote:
>
> 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
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/
c wrote:
>
> 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
05-26-2004, 01:23 AM
#70
Guest
Posts: n/a
Re: Just had my engine dyno'd and air fuel ratio checked
Or, could it be part of the break in process of the engine?
Bill
> What would happen if the balanced Flywheel and Clutch plate were not
> aligned. Would that be enough cause a vibration? I've had the timing off
> before and it didn't feel like that.
>
> Sheeezzzhh...
>
> Bill
>
Bill
> What would happen if the balanced Flywheel and Clutch plate were not
> aligned. Would that be enough cause a vibration? I've had the timing off
> before and it didn't feel like that.
>
> Sheeezzzhh...
>
> Bill
>
