RocknTJ

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

"RocknTJ" <jetowle@***.net> wrote in message
news:d5Usc.21402$7y5.12374@fed1read03...
> (This is from the last page of the post)
>
> http://www.toughstuffproducts.com/Daless2/donehp.jpg
> HP:
> 124.3 stock
> 212.5 SC'd
> Curves together: http://www.toughstuffproducts.com/Daless2/hpsc.jpg
>
>
> http://www.toughstuffproducts.com/Daless2/donetq.jpg
> Torque:
> 163.2 stock
> 271.9 SC'd
> Curves together: http://www.toughstuffproducts.com/Daless2/tqsc.jpg
>
> MPG almost unchanged.
>
> --James
>
> PS - I would take the torque, but I am not sure I would spend that kind of
> money on it.
>
> "L.W. (ßill) ------ III" <----------@***.net> wrote in message
> news:40B403A3.84218D4C@***.net...
> > 129 HP Stock and with the supercharger:
> > http://jeepsunlimited.com/forums/sho...hreadid=511089
> > God Bless America, ßill O|||||||O
> > mailto:-------------------- http://www.----------.com/
> >
>
>

serg

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
> > > >
> > > >
> > >
> > >
> >
> >
>
>

serg

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
> > > >
> > > >
> > >
> > >
> >
> >
>
>

serg

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
> > > >
> > > >
> > >
> > >
> >
> >
>
>

serg

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
> > > >
> > > >
> > >
> > >
> >
> >
>
>

serg

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
>
>

serg

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
>
>

serg

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
>
>

serg

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
>
>

William Oliveri

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
> >
> >
>
>