Ram air

Turbocharging can be set to two different levels:
Turbonormalizing, which brings manifold pressure to sea level
pressure; and boosting, which raises manifold pressures to more than
30" Hg. If an engine is boosted, the air density in the cylinder at
the bottom of the intake stroke could be well above atmospheric.

Dan

Careful, Bertie the ButtlippS cross-posted this a few messages back. You're
trying to explain something to someone on a kook group.

On Jun 2, 11:08*pm, wrote:
On Jun 2, 8:00 pm, Billy Crabs wrote:





On Jun 2, 5:12 pm, Tony wrote:

Ram air is only as useful the allowing air to get to your carburater
faster but is not necessarily used. When your piston is on its intake
stroke(vaccum) your combustion chamber can only draw in enough air
that is in conjuction to the chambers volume and all other air that is
present after the compression stroke is exported to engines smog
devices and is recirculated only AFTER being filtered. *All engines
come off the assembly lines, be it an airplane motor or a vehicle
motor, to draw the amount of air that it needs to run at opptimum
performance. *Ram Air is a myth and don't try to throw "turbo" into
the conversation because turbo is recircualted exhaust and still has
unburnt fuel in the fumes.

I think you are quite wrong. Ram air in fact gives us a half inch or
so more manifold pressure, and that increases the total weight of the
air-fuel mixture in the cylinder. Reduce your 'it doesn't matter
argument to an extreme to see how it fails.

As for turbos, the turbine is powered by the exhaust gasses coming
from the engine, the exhaust gas itself is not reintroduced into the
cylinders. The turbine itself could be powered by an electric motor,
for that matter. That was the model for my tongue in cheek comment
about using a shop vac to increase manifold pressure.

The air going into the manifold has the same atmospheric weight as if
it was outside the manifold, what makes it denser is the addition of
fuel into the air/fuel mixture, unless the air is in a perfect vaccum
it will not increase in pressure and most certainly not density and
the turbos do reintroduce fuel back into the combustion mixture, If
you've ever seen a read out of carbon emissions for a non turbo
vehicle it still has enough unburnt fuel to power your vehicle for
another 5% of your fuel consumption *and turbos IF powered by a
motorized turbine are as useless as ram air because of the statement I
made in my previous post. your intake is only as much as the volume of
your cylinders

* * * * * * Turbocharging can be set to two different levels:
Turbonormalizing, which brings manifold pressure to sea level
pressure; and boosting, which raises manifold pressures to more than
30" Hg. If an engine is boosted, the air density in the cylinder at
the bottom of the intake stroke could be well above atmospheric.

I'm sorry to keep disagreeing but, but the pressure in which(if you
can call it pressure) goes through a manifold is increased by MAP
sensors which measure atmospheric pressure and regulates air fuel
mixture, it has nothing to do with "ram air" and I do agree that that
the density of the air/mixture is increased by the vaccum caused by a
piston at bottom dead center but we were talking about air before it
reaches the cylinder and the speed of which it arrives to carburation.

* * * * *Dan- Hide quoted text -

- Show quoted text -

On Jun 3, 6:38*am, Billy Crabs wrote:
On Jun 2, 9:28*am, Bertie the Bunyip wrote:





"Maxwell" luv2^fly99@cox.^net wrote in news:jTR0k.192$js1.25
@newsfe24.lga:

"Bertie the Bunyip" wrote in message
.. .
"Maxwell" luv2^fly99@cox.^net wrote in
:

"Bertie the Bunyip" wrote in message
...
Didn't know any production aircraft had that. Well, to some extent
almost every lightplane does . that's why the carb air intake faces
forwards in most of them.Everything is a balancing act with an
airplane. More air = more drag. You could try putting a couple of
woks with tubes out the back to boost your MP, but you're going to
pay for it. !Moooney must have spotted an area of the cowl that
would
not penalise you in this way and decided to utilise it. Really
clever
homebuilders do a lot of this kind of stuff as well as, and
probably
more more importantly, dealing with cooling drag.
Have you put the other speed mods on your airplane? I think there's
nearly ten knots available in seals and various other tidy it up
fairings.

Bertie

Dumb ass.

Its because the size of the scoop increases volume (not pressure),
and
you already have too much.

Nope.

Bertie

How would you know, dumb ass?

I know everything, obviously.

Bertie- Hide quoted text -

- Show quoted text -

Ram air is only as useful the allowing air to get to your carburater
faster but is not necessarily used. When your piston is on its intake
stroke(vaccum) your combustion chamber can only draw in enough air
that is in conjuction to the chambers volume and all other air that is
present after the compression stroke is exported to engines smog
devices and is recirculated only AFTER being filtered. *All engines
come off the assembly lines, be it an airplane motor or a vehicle
motor, to draw the amount of air that it needs to run at opptimum
performance. *Ram Air is a myth and don't try to throw "turbo" into
the conversation because turbo is recircualted exhaust and still has
unburnt fuel in the fumes.- Hide quoted text -

I would think the air getting to the cyclinder faster is important,
given the little time available for the intake to occur. If you
analyse the take off performance data of C172 ( which I have) you can
see quite clearly that for the same air density, better performance
( ie shorter take off distance) is obtained at higher temperatures
( which of course means higher pressure). I , and others, interpret
this as the higher pressure providing a stronger driving force to fill
the cylinder quicker.
Terry
PPL Downunder

On Jun 2, 3:30 pm, terry wrote:
On Jun 3, 6:38 am, Billy Crabs wrote:

On Jun 2, 9:28 am, Bertie the Bunyip wrote:

"Maxwell" luv2^fly99@cox.^net wrote in news:jTR0k.192$js1.25
@newsfe24.lga:

"Bertie the Bunyip" wrote in message
.. .
"Maxwell" luv2^fly99@cox.^net wrote in
:

"Bertie the Bunyip" wrote in message
...
Didn't know any production aircraft had that. Well, to some extent
almost every lightplane does . that's why the carb air intake faces
forwards in most of them.Everything is a balancing act with an
airplane. More air = more drag. You could try putting a couple of
woks with tubes out the back to boost your MP, but you're going to
pay for it. !Moooney must have spotted an area of the cowl that
would
not penalise you in this way and decided to utilise it. Really
clever
homebuilders do a lot of this kind of stuff as well as, and
probably
more more importantly, dealing with cooling drag.
Have you put the other speed mods on your airplane? I think there's
nearly ten knots available in seals and various other tidy it up
fairings.

Bertie

Dumb ass.

Its because the size of the scoop increases volume (not pressure),
and
you already have too much.

Nope.

Bertie

How would you know, dumb ass?

I know everything, obviously.

Bertie- Hide quoted text -

- Show quoted text -

Ram air is only as useful the allowing air to get to your carburater
faster but is not necessarily used. When your piston is on its intake
stroke(vaccum) your combustion chamber can only draw in enough air
that is in conjuction to the chambers volume and all other air that is
present after the compression stroke is exported to engines smog
devices and is recirculated only AFTER being filtered. All engines
come off the assembly lines, be it an airplane motor or a vehicle
motor, to draw the amount of air that it needs to run at opptimum
performance. Ram Air is a myth and don't try to throw "turbo" into
the conversation because turbo is recircualted exhaust and still has
unburnt fuel in the fumes.- Hide quoted text -

I would think the air getting to the cyclinder faster is important,
given the little time available for the intake to occur. If you
analyse the take off performance data of C172 ( which I have) you can
see quite clearly that for the same air density, better performance
( ie shorter take off distance) is obtained at higher temperatures
( which of course means higher pressure). I , and others, interpret
this as the higher pressure providing a stronger driving force to fill
the cylinder quicker.
Terry
PPL Downunder

Higher air temps mean a lower air viscosity, reducing
induction drag, and faster and more complete vaporization of the fuel.

Dan

On Jun 3, 9:11*am, wrote:
On Jun 2, 3:30 pm, terry wrote:





On Jun 3, 6:38 am, Billy Crabs wrote:

On Jun 2, 9:28 am, Bertie the Bunyip wrote:

"Maxwell" luv2^fly99@cox.^net wrote in news:jTR0k.192$js1.25
@newsfe24.lga:

"Bertie the Bunyip" wrote in message
.. .
"Maxwell" luv2^fly99@cox.^net wrote in
:

"Bertie the Bunyip" wrote in message
...
Didn't know any production aircraft had that. Well, to some extent
almost every lightplane does . that's why the carb air intake faces
forwards in most of them.Everything is a balancing act with an
airplane. More air = more drag. You could try putting a couple of
woks with tubes out the back to boost your MP, but you're going to
pay for it. !Moooney must have spotted an area of the cowl that
would
not penalise you in this way and decided to utilise it. Really
clever
homebuilders do a lot of this kind of stuff as well as, and
probably
more more importantly, dealing with cooling drag.
Have you put the other speed mods on your airplane? I think there's
nearly ten knots available in seals and various other tidy it up
fairings.

Bertie

Dumb ass.

Its because the size of the scoop increases volume (not pressure),
and
you already have too much.

Nope.

Bertie

How would you know, dumb ass?

I know everything, obviously.

Bertie- Hide quoted text -

- Show quoted text -

Ram air is only as useful the allowing air to get to your carburater
faster but is not necessarily used. When your piston is on its intake
stroke(vaccum) your combustion chamber can only draw in enough air
that is in conjuction to the chambers volume and all other air that is
present after the compression stroke is exported to engines smog
devices and is recirculated only AFTER being filtered. *All engines
come off the assembly lines, be it an airplane motor or a vehicle
motor, to draw the amount of air that it needs to run at opptimum
performance. *Ram Air is a myth and don't try to throw "turbo" into
the conversation because turbo is recircualted exhaust and still has
unburnt fuel in the fumes.- Hide quoted text -

I would think the air getting to the cyclinder faster is important,
given the little time available for the intake to occur. * If you
analyse the take off performance data of C172 ( which I have) *you can
see quite clearly that for the same air density, better performance
( ie shorter take off distance) is obtained at higher temperatures
( which of course means higher pressure). I , and others, interpret
this as the higher pressure providing a stronger driving force to fill
the cylinder quicker.
Terry
PPL Downunder

* * * * * *Higher air temps mean a lower air viscosity, reducing
induction drag, and faster and more complete vaporization of the fuel.

I thought that also ( the viscosity bit) , but viscosity of air
actually increases with increasing temperature
http://www.engineeringtoolbox.com/ai...ity-d_601.html

the vaporization theory might hold though. I will look into that one.

Terry
PPL Downunder

On Mon, 2 Jun 2008 13:38:57 -0700 (PDT), Billy Crabs
wrote:

On Jun 2, 9:28*am, Bertie the Bunyip wrote:
"Maxwell" luv2^fly99@cox.^net wrote in news:jTR0k.192$js1.25
@newsfe24.lga:









"Bertie the Bunyip" wrote in message
.. .
"Maxwell" luv2^fly99@cox.^net wrote in
:

"Bertie the Bunyip" wrote in message
...
Didn't know any production aircraft had that. Well, to some extent
almost every lightplane does . that's why the carb air intake faces
forwards in most of them.Everything is a balancing act with an
airplane. More air = more drag. You could try putting a couple of
woks with tubes out the back to boost your MP, but you're going to
pay for it. !Moooney must have spotted an area of the cowl that
would
not penalise you in this way and decided to utilise it. Really
clever
homebuilders do a lot of this kind of stuff as well as, and
probably
more more importantly, dealing with cooling drag.
Have you put the other speed mods on your airplane? I think there's
nearly ten knots available in seals and various other tidy it up
fairings.

Bertie

Dumb ass.

Its because the size of the scoop increases volume (not pressure),
and
you already have too much.

Nope.

Bertie

How would you know, dumb ass?

I know everything, obviously.

Bertie- Hide quoted text -

- Show quoted text -

Ram air is only as useful the allowing air to get to your carburater
faster but is not necessarily used. When your piston is on its intake
stroke(vaccum) your combustion chamber can only draw in enough air
that is in conjuction to the chambers volume and all other air that is
present after the compression stroke is exported to engines smog
devices and is recirculated only AFTER being filtered. All engines
come off the assembly lines, be it an airplane motor or a vehicle
motor, to draw the amount of air that it needs to run at opptimum
performance. Ram Air is a myth and don't try to throw "turbo" into
the conversation because turbo is recircualted exhaust and still has
unburnt fuel in the fumes.

**************************************
Billy

Don't know where you got ur data. My turbo had the turbine wheel
turned by the exhaust. The turbine wheel was connected to the
compressor wheel which took ambient air and compressed it and ran it
thru the carb and into the engine. Always has and always will.

You may be talking about an auto engine and the exhaust gas
recirculation system to help meet EPA standards.?

Big John

Billy Crabs wrote in news:30acf9c1-0253-49b5-
:

On Jun 2, 9:28*am, Bertie the Bunyip wrote:
"Maxwell" luv2^fly99@cox.^net wrote in news:jTR0k.192$js1.25
@newsfe24.lga:









"Bertie the Bunyip" wrote in message
.. .
"Maxwell" luv2^fly99@cox.^net wrote in
:

"Bertie the Bunyip" wrote in message
...
Didn't know any production aircraft had that. Well, to some
extent
almost every lightplane does . that's why the carb air intake
faces
forwards in most of them.Everything is a balancing act with an
airplane. More air = more drag. You could try putting a couple
of
woks with tubes out the back to boost your MP, but you're going
to
pay for it. !Moooney must have spotted an area of the cowl that
would
not penalise you in this way and decided to utilise it. Really
clever
homebuilders do a lot of this kind of stuff as well as, and
probably
more more importantly, dealing with cooling drag.
Have you put the other speed mods on your airplane? I think
there's
nearly ten knots available in seals and various other tidy it up
fairings.

Bertie

Dumb ass.

Its because the size of the scoop increases volume (not
pressure),
and
you already have too much.

Nope.

Bertie

How would you know, dumb ass?

I know everything, obviously.

Bertie- Hide quoted text -

- Show quoted text -

Ram air is only as useful the allowing air to get to your carburater
faster but is not necessarily used. When your piston is on its intake
stroke(vaccum) your combustion chamber can only draw in enough air
that is in conjuction to the chambers volume and all other air that is
present after the compression stroke is exported to engines smog
devices and is recirculated only AFTER being filtered. All engines
come off the assembly lines, be it an airplane motor or a vehicle
motor, to draw the amount of air that it needs to run at opptimum
performance. Ram Air is a myth and don't try to throw "turbo" into
the conversation because turbo is recircualted exhaust and still has
unburnt fuel in the fumes.


Yeah, of course, As i think someone else pointed out elsewhere in this
thread, there were some installations where the prop was positioned to
provide a pulse at the time the intake valves opened. Easy on a four
cylinder. There were props made for these that had a slightly larger
chord at the point on the prop span where the intake was. Didn't seem to
become popular for whatever reason..


Bertie