[Bigg Tim]

Is the MAP sensor on the left side of the IM on the 1st pic in post 39?

 

[whooosh]

I didn't take it apart but here's the pictures I have.[/b]

do you have a pic of intake side where the TB mounts?
Maybe the measurement as well in mm?

Thanks in advance if you can post it!

 

[ATE BALLER]

Is the MAP sensor on the left side of the IM on the 1st pic in post 39?[/b]

I beleive the MAP sensor is the little black square in the bottom right of that first picture.

 

[mtxpert]

Is the MAP sensor on the left side of the IM on the 1st pic in post 39?[/b]

See attached pics

do you have a pic of intake side where the TB mounts?
Maybe the measurement as well in mm?

Thanks in advance if you can post it![/b]

Sorry, no, that's all I have.

 

[ATE BALLER]

OK, another question conserning the cossie...

If it were to be installed on the motor, would the slight mismatch of the inlets impede the airflow, or would the larger diameter make up for that? Would it be possible to develope an adapter that protruded into the manifolds runners about an inch or so that had a "nicer" split to counter any airflow restriction?

Just a thought.

 

[franchize]

Our intake manifold uses a variable swirl system

The purpose of the variable swirl system is to lower emissions at cold-engine start.

At cold-engine start the VSS increases intake airflow speed by closing the shutter valve, resulting in an improved air-fuel mixture quality.

The air swirl also promotes atomization of the air-fuel mixture.

 

[WhightLightn]

On a NA motor, resonance tuning does help. On an FI car, resonance effects are overridden by boost. Resonance doesn't work because its dependent on air density and in an FI motor the air density is constantly changing; secondly, any gains from it are absolutely overwhelmed and its more important to decrease air resistance and that decrease comes from bigger ports and bigger plenums.[/b]

Not true. Many turbo motors from the factory use a helmholtz resonation theory application for the intake manifold design.

 

[ATE BALLER]

So, will our air not mix with our fuel? Mine's been disabled and locked open for a looooooong time now, and I've had no problems at all besides a VERY SLIGHTLY rough idle when I start it in cold weather ( below 45* or so) for about 3 minutes. I wait til the engine is warm anyway before I take off, so I don't see that being a problem for me. I don't get smoke at all besides once when I left it running for a half an hour or so because of a big emergency. I don't get hesitation or studdering at all since it's been that way. I don't feel like paying Mazda $250.00 or whatever it was for the actuator that's broke, so I think I'm just going to remove the whole system.

One question though; where the rod comes out, is there a bolt or something that plugs the hole back up? Or should I take out the rod to get the flappers out, and then put the rod back in? I don't want to drive around with a hole in the manifold. Any of you 6 guys that removed the system care to chime in?

 

[sixme]

From what I am hearing it sounds like the systems are close to the same with just the intake looking different. As stated you will get kinda a rough idle in cold starts but then it goes away and everything is fine. Those butterflies block air in cold weather to atomize full better but when the car is warmed up they open all the way up. But they are still in the way.

here is the link

http://www.mazda3forums.com/index.php?topic=71673.0

 

[Road Rage]

From what I am hearing it sounds like the systems are close to the same with just the intake looking different. As stated you will get kinda a rough idle in cold starts but then it goes away and everything is fine. Those butterflies block air in cold weather to atomize full better but when the car is warmed up they open all the way up. But they are still in the way.

here is the link

http://www.mazda3forums.com/index.php?topic=71673.0[/b]

thanks for the link there is alot of good 2.3 dyi's on there and i think i have my new weekend project because if they felt gains on the na car then we will defenatly have gains on our turbo cars.

also there is a dyi on the ballance shaft removal thats a really good read

So, will our air not mix with our fuel? Mine's been disabled and locked open for a looooooong time now, and I've had no problems at all besides a VERY SLIGHTLY rough idle when I start it in cold weather ( below 45* or so) for about 3 minutes. I wait til the engine is warm anyway before I take off, so I don't see that being a problem for me. I don't get smoke at all besides once when I left it running for a half an hour or so because of a big emergency. I don't get hesitation or studdering at all since it's been that way. I don't feel like paying Mazda $250.00 or whatever it was for the actuator that's broke, so I think I'm just going to remove the whole system.

One question though; where the rod comes out, is there a bolt or something that plugs the hole back up? Or should I take out the rod to get the flappers out, and then put the rod back in? I don't want to drive around with a hole in the manifold. Any of you 6 guys that removed the system care to chime in?[/b]

according to the 3 site there is no hole because the rod doesnt go all the way throught the manifold and you reinstal the motor to block off where the rod comes though

Not true. Many turbo motors from the factory use a helmholtz resonation theory application for the intake manifold design.[/b]

can you post some links on modern cars useing this?

 

[Gandalf]

I keep hearing swirl valve. . . I don't think these things have anything to do with our swirl valve. The Sentra Spec-V has a very similar intake manifold design, it opens at higher RPM because the engine needs more air. It's pretty simple.

 

[ATE BALLER]

Look at the PDF for the emissions systems. It says in big bold print "VARIABLE SWIRL VALVE SYSTEM".

 

[Gandalf]

Look at the PDF for the emissions systems. It says in big bold print "VARIABLE SWIRL VALVE SYSTEM".[/b]

And? The PDF says O2 SENSOR also somewhere, that doesn't make this manifold butterfly an 02 Sensor does it? These are intake runner butterfly valves, not a variable swirl valve (which I believe is actually on the backside of the motor near the turbo).

 

[ATE BALLER]

Wow. No, the whole idea of a variable swirl valve system is to cause a SWIRL (turbulant air flow) as it enters the cylinder to aid in atomization with the fuel. The part on my car that is broken is the VARIABLE SWIRL VALVE ACTUATOR as indicated in another PDF and as told to me by a tech at the dealership. It is the grey actuator that sits behind/under your BOV, attached to the lever that turns the rod, which the flappers in the intake manifold are attached to. Sorry, but you're wrong on this one.

 

[ghettospeed]

Not true. Many turbo motors from the factory use a helmholtz resonation theory application for the intake manifold design.[/b]

For this to be a helmholtz resonator manipulation these valves' open and closing would need to change either plenum volume or runner length.

They simply block one of the ports, (at cold start and low rpms) to optimize VELOCITY into the cylinder which also causes, oh yes, swirl, hence why its called a SWIRL VALVE! This is because you are letting high velocity air into the cylinder from only one side. But that does not change the resonance.

Closing one port increases air velocity but does not change resonance.

Swirl valves are mostly for driveability and emissions and do not affect peak performance very much except at the top end, where the valve flapper acts as a restriction.

The SWIRL part of the SWIRL VALVE is because you let the air in on only one side. The air goes from a high pressure area at the valve and rushes to the low pressure area on the opposite side of the cylinder, thereby inducing swirl and it helps alot to mix the fuel.

This is to compensate for the achilles heel of DI. By injecting into the cylinder, there isn't much time or turbulence to aid in air/fuel mixing at low rpms. This unmixing of air/fuel can lead to hotspots in the cylinder. By having a single port you increase velocity into the cylinder and better distributes the air/fuel and it counters this situation.

Without the swirl valve, as much as I dislike it, it could cause carbon deposits on the combustion chamber and valves.