i have a question... on the standard intake there is a big plastic rectangle looking thing that sits on top. what does it do??? does it do anything if removed???? it is near the motor...
hope u understand what i mean lol

they aparentley make the air intake quieter (resanator). you can take them off and put in milk lids, you will get a little inducation noise and thats about all

wont it suck it in?????? how do u keen it in it?

The intake resonator? Sometimes removed and the hole plugged with a mc.cormic spice jar lid?
If you take ANYTHING out after the MAF sensor, make sure you plug the hole! Otherwise your car wil suck in un-filtered, un-measured air, and since more air is going in than the maf sensor reads, it will run lean.

There are a few theories on what intake resonators do;
a) intake noise surpression
b) provide a slight "tuned length intake" for slight power gains, similar to what people do with tuning intake and exhausts on a 2 stroke, but with a lesser effect.
c) backfire chamber, to absorb some of the blast if the engine backfires through the intake so it doesn't blow the filter box apart as easily (probably not a concern on a stock magna running reasonably well)

so if i take it out and plug it, whats the outcome????

little more noise, not much else. I put aluminium bungs in my TR, didnt really notice much at all, did it again on the KH anyway. Apparently it makes a bigger difference with a pod filter or at least a K&N. Theres one resonator above the intake, one below, and one under some snorkels.

so if i take it out and plug it, whats the outcome????

Slight induction noise increase and a very minimal power loss on take off due to reducing the volumetric effiency of the intake.
Many will call bullshit on that but ive done my reasearch and that is my conclusion.

might need some one to do it for me, see the difference

little more noise, not much else. I put aluminium bungs in my TR, didnt really notice much at all, did it again on the KH anyway. Apparently it makes a bigger difference with a pod filter or at least a K&N. Theres one resonator above the intake, one below, and one under some snorkels.

whats a aluminum bung???

Nice grunty noise from your intake, made even better with a k&n filter. There is a resonator on the underside of the pipe too, and 1 on the snorkel. There are no negative side effects at all, just a nice note from the engine.

DIY. its 1 screw, and one orange juice bottle cap, take you 2 minutes

do u need tape or anything to hold it on?

Don't use spice jar lids, they work but dodgy as hell.

Get the correct sized welch brass plug.

and where do u get one of them from?? expensive??

and does it do anything with a standard intake system??

It's the same as a spice jar lid, just a much better job of it.

Get it at any supercrap, ripco etc

I think 30mm is the size, just use the existing clamps on top and you're done.

I even sprayed the plug black so it's not that noticeable.

They're like 4 bucks each so not gonna break the bank.

can u chuck up a pic??

do u need tape or anything to hold it on?

I just used the clamp that was originally around the resonator.

can u chuck up a pic??

There's nothing to see dude, just google welch plug and you'll see.

You put it in the inside of intake pipe hole, once you take off the resonator you'll see a rubber lip inside which makes it impossible for the plug to go anywhere.

might give it a go, see how it goes. make any difference with a standard intake??

http://picturestack.com/475/786/sz91002972Ife.th.jpg (http://picturestack.com/475/786/sz91002972Ife.jpg)
http://picturestack.com/475/787/tLG1002973RGg.th.jpg (http://picturestack.com/475/787/tLG1002973RGg.jpg)

Can someone confirm the size...?

The standard thingamajig rubs on my strut brace (http://www.aussiemagna.com/forums/showthread.php?t=58568&p=1303911&viewfull=1#post1303911) so I've been meaning to replace it...

I think it was 39.7-40mm from memory when I made the ones in mine. Theyre a pain to get out though as we only had 50mm bar stock at work, there isn't enough edge for it to sit over the plastic on the intake to get a grip on it to pull it out, you have to screwdriver around the edge. I'll see if Ican get the top one out and measure it tomorrow.

It's better to get the right plug to sit inside the hole instead of over it.

so dingers what size is yours?? or would u recomend to fit inside??

It was 30mm from memory, and inside is just easier to do as well as 100% air tight.

You don't even need the clamp since the plug will be a tight fit anyway.

Take your resonator off and have a look inside, you'll see that it's physically impossible to push in the plug.

When you go get the plug just ask them before you pay for it if you can see if it fits the hole, I'm sure they'll let you walk out for 2 seconds with them.

im from north of adelaide.... they wont let me do that bahahahahahhahaha

I really have to wonder what the point of removing the resonator from an otherwise stock engine is. After all, Mitsubishi didn't go to the expense of designing & fitting it just for the sake of adding something of no benefit. Even if you can't measure the effect, you can be sure there is one. The effect might have nothing to do with power output at all. For example, it may be designed to manage fuel:air ratios on over-run/deceleration, preventing overly-rich or lean mixtures, which no amount of seat-of-the pants or dyno testing might ever tell you anything about.

thats my thought. do i touch it or not, if i do whats it gonna do... nothing.... hmmmmmm now what to do??

I wouldn't be taking the resonators out if I were you. I took mine out, and after chatting with Mal, he stated that they can be an air reserve. Also, you won't get a great deal of noise unless you take the snorkel off............

well i dont have the snorkel on, trying pipes and pods etc right now

After looking around at other car forums, trying to get to the real reason of the resonator. I wasn't convinced by anyones effort to explain its purpose convincingly.
So... I thought I would have a go.
the mystery of the resonator
It is not there reduce to the noise of the intake, but it may do it by in due course of its real duty. Its a resonating air reducer.

The Theory

Read this.
When air is forced into a cavity, the pressure inside increases. When the external force pushing the air into the cavity is removed, the higher-pressure air inside will flow out. However, this surge of air flowing out will tend to over-compensate, due to the inertia of the air in the neck, and the cavity will be left at a pressure slightly lower than the outside, causing air to be drawn back in. This process repeats with the magnitude of the pressure changes decreasing each time.

This effect is akin to that of a bungee-jumper bouncing on the end of a bungee rope, or a mass attached to a spring. Air trapped in the chamber acts as a spring. Changes in the dimensions of the chamber adjust the properties of the spring: a larger chamber would make for a weaker spring, and vice-versa.

The air in the port (the neck of the chamber) has mass. Since it is in motion, it possesses some momentum. A longer port would make for a larger mass, and vice-versa. The diameter of the port is related to the mass of air and the volume of the chamber. A port that is too small in area for the chamber volume will "choke" the flow while one that is too large in area for the chamber volume tends to reduce the momentum of the air in the port.
Source (http://en.wikipedia.org/wiki/Helmholtz_resonance)


What I can gather from this effect is.

After the air in the intake is released from the negative pressure from acceleration, the air push pushes back and forth, until it equalizes, back to the required (negative) draw of the motor, these pressure resonances, could sometimes starve a cylinder/s from air, til the resonances have finished and pressure is equalized to the engines demand.
The remedy.

The resonator acts as a baffle/equalizing chamber to prevent this occurring. Often called a tuned length.

So would it be fair to say......
1. that you will have a smoother running engine if you have the resonator fitted. It's benefits would best assist smoothness after accelerating/deaccelerating/starting or any change in RPM.
2. its not really sound resonator prevention, but air. To prevent the air in the intake from 'chuffing' very quickly.


My advice is with Mal, put them back on.
Obviously, this is not required on forced induction systems.

If I were asked to try and demonstrate the effects of a (Mr Potatoe Head lol Si) resonator in action, I would get some else to operate the car, and observe the motor after jabs of the accelerator pedal, I would bet the engine with the resonator fitted would not shake as much and recover rpm almostly instantly, the same engine without the resonator would not and more than likely shake more than the other.


What do you reckon, have I hit it on the head.
Is this crap....
Is this a very probable reason that an educated experienced engineer created it, and I agree.

Thoughts?

I agree, i asked a long time ago on here if the resonator was part of the intake tuning along with runner lenth, and was shot down.

Hmmm well I'll leave it on lol

Slight induction noise increase and a very minimal power loss on take off due to reducing the volumetric effiency of the intake.
Many will call bullshit on that but ive done my reasearch and that is my conclusion.


Yes you are right and agree with you volume of air is important on take off...

i have a question... on the standard intake there is a big plastic rectangle looking thing that sits on top. what does it do??? does it do anything if removed???? it is near the motor...
hope u understand what i mean lol

•Increase the diameter of the tubing, which allows increased flow.
•Smoothing the inner piping of the intake, reducing restrictions.
•Providing more direct routes to the throttle body.
•Using specific lengths of intake tubing in order to create more power in different specific engine speeds.
•Utilizing high-flow, high-filtering air filters.
Hope this info will help you

The resonance of air rushing in and out of the chamber is tuned to eliminate another frequency that causes unwanted noise. I.e. they cancel each other out. Mitsi used several techniques to get it right over many product life cycles, that's why you see variances from one model to the next in other parts of the CAI.

The only thing I've noticed by removing it, is more induction noise. But how much I cant tell, as I have modified my CAI and its loud enough (which I like lol).

If you had blow air through a pipe, and if I could measure how quickly/efficiently you could do it, would you score better with still undisturbed air, or with air that its mass vibrated back n forward from its own disturbances.
But what is it's worth in an intake in a combustion engine?
Is the noise removal the primary goal, or is the primary objective the resonance itself?

IMO, I think the basic laws of physics answer this, for every action there is an equal and opposite reaction.
So my line thinking goes, the energy used to create the noise is taken from the energy required to move the air through the intake.

If you had blow air through a pipe, and if I could measure how quickly/efficiently you could do it, would you score better with still undisturbed air, or with air that its mass vibrated back n forward from its own disturbances.
But what is it's worth in an intake in a combustion engine?
Is the noise removal the primary goal, or is the primary objective the resonance itself?

You can probably answer the question yourself with an analogy "What is the purpose of the resonator on the exhaust"...high pressure and low pressure cancel each other out...therefore the purpose is to reduce noise. Nothing to do with increasing air flow. In fact removing the resonator has been shown to increase air flow from an exhaust, with no changes to emissions.

Now relate that to the resonator in the CAI, high pressure vs low pressure as air low moves over the resonator opening.

The components that influence air flow into the engine are mainly, air filter, intake air piping, mass air sensor, throttle body and intake manifold.

IMO, I think the basic laws of physics answer this, for every action there is an equal and opposite reaction.
So my line thinking goes, the energy used to create the noise is taken from the energy required to move the air through the intake.

You have a good point. Wind noise is created by disturbances, which is a restriction of flow. However your using newtons laws of motion. Your thinking of conservation of energy laws where energy can neither be created nor be destroyed: it can only be transformed from one state to another

The components that influence air flow into the engine are mainly, air filter, intake air piping, mass air sensor, throttle body and intake manifold.

You are forgetting one big thing, that is the real cause of the of the flow itself, the bursts of negative pressure create by the engine itself.


In fact removing the resonator has been shown to increase air flow from an exhaust, with no changes to emissions.

Interesting, is there a reference for the testing conditions.

But I do totally understand that manufacturers make changes to sacrifice performance over the need for comfort, the 380 intake intake is one, that comes to mind.

You have a good point. Wind noise is created by disturbances, which is a restriction of flow. However your using newtons laws of motion. Your thinking of conservation of energy laws where energy can neither be created nor be destroyed: it can only be transformed from one state to another

Thanks for clearing that up for the uneducated..... Me.....:)

SHOOT:
You are correct - it is a noise suppressor. It works thus:

Noise is actually a series of pressure pulses, in this case travelling up and down the air intake to the engine. The pulses are generated by the suction of the engine and when teh intake valve opens, a negative pulse is generated. This will travel back along the intake manifold until it reaches a reflecting surface where it will reflect back towards the engine. Then it will bounce back as a positive pressure wave. This is all fairly basic stuff. the effect you hear is when the pulses all align and magnify each other. Then it becomes a noise you can hear over and above the engine noise. The effect on engine performance will be minimal because we are talking about miniscule pressure differences - the ear can detect amazingly small pressure pulses.

I designed a similar resonator for a 4.2 m diameter pipeline full of water. This was to minimise noises being generated by the blades of the turbine runner in a hydro-electric machine. The principle is the same - it is all about reducing noise.

You are forgetting one big thing, that is the real cause of the of the flow itself, the bursts of negative pressure create by the engine itself.

Well, thank you for reminding me there is an Engine amongst all of the those components...lol
I'll leave the rest to your own research. Report back your results. :)

SHOOT:
Sorry - my fingers work faster than my brain these days. What I meant to say is that the resonator senses the pressure pulses and it in turn reflects the pulse back into the main airflow stream. When it sends the pulse back out, it is of oppostie value ie if a positive pulse comes past, by the time the next positive pulse comes along, it is cancelled by a negative pulse being spat out of the resonator. Same thing with negative pulses - they are cancelled out by a positive pulse from the resonator.

Go to this link to see an animation of what erad is taking about in terms of how a resonator works. (http://auto.howstuffworks.com/muffler4.htm)

Thanks GTVi, I'll look at the link in a minute.
However.
Although the air percussion might be there, it may even be measurable, but its sounds as though its negligable, and no negative affect at all.
And perhaps, just there solely for noise refinement.
Pity, is was a good theory.
You used to work there? Didn't you?

http://www.aussiemagna.com/forums/attachment.php?attachmentid=44791

Hi guys what do you think about this CAI???

Thanks GTVi, I'll look at the link in a minute.
However.
Although the air percussion might be there, it may even be measurable, but its sounds as though its negligable, and no negative affect at all.
And perhaps, just there solely for noise refinement.
Pity, is was a good theory.
You used to work there? Didn't you?

You will notice, say on a TE/TF there is a resonator under the air intake at the scoop end....look at a later model TL/KL and you will notice it was removed...makes you wonder. MMAL made various progressive changes, and some were dropped altogether due to cost. In other words, it made no difference to the end product for the consumer. I hope that explains it better.


http://www.aussiemagna.com/forums/attachment.php?attachmentid=44791

Hi guys what do you think about this CAI???

I have done something similar. Needs a longer pipe to get cold air from outside of the car, located in a high pressure area. I.e. behind front grill etc...

You will notice, say on a TE/TF there is a resonator under the air intake at the scoop end....look at a later model TL/KL and you will notice it was removed...makes you wonder. MMAL made various progressive changes, and some were dropped altogether due to cost. In other words, it made no difference to the end product for the consumer. I hope that explains it better.



I have done something similar. Needs a longer pipe to get cold air from outside of the car, located in a high pressure area. I.e. behind front grill etc...

Thanks for your input here but here is another photo and have look in my photo album CAI Thanks for looking and your input...

Look here http://www.aussiemagna.com/forums/attachment.php?attachmentid=44792

You will notice, say on a TE/TF there is a resonator under the air intake at the scoop end....look at a later model TL/KL and you will notice it was removed...makes you wonder. MMAL made various progressive changes, and some were dropped altogether due to cost. In other words, it made no difference to the end product for the consumer. I hope that explains it better.

They had another on the earlier 3rd gens, below the top Resonator we are taking about. Marty.. I know you know that but I couldn't leave it out.

I have done something similar. Needs a longer pipe to get cold air from outside of the car, located in a high pressure area. I.e. behind front grill etc...

I have the NZ VRX intake, Partly shrouded with similar to Doddski's (http://img.photobucket.com/albums/v146/doddski_03/Verada%20Thread/Amping270620111-1.jpg), with a enlarged hole (http://i228.photobucket.com/albums/ee217/SH00T/Side.jpg).

I still wont be putting in my homemade welch plug, made from my old intake, the car seems to start faster and smoother with the resonator.

But I might block the whole for a little while, just to see how it sounds, I got a dog fitted after my cat today. :0

I have the NZ VRX intake, Partly shrouded with similar to http://img.photobucket.com/albums/v146/doddski_03/Verada%20Thread/Amping270620111-1.jpgs, with a enlarge hole.

But, I still wont be putting in my homemade welch plug, made from my old intake, the car seems to start faster and smoother with the resonator.

You are getting very good volume of air keeping resonators on....

Yeah Sorry Mate, Thats Doddski's,,, This is mine (http://i1191.photobucket.com/albums/z467/Shootmarty/Batteryintakeshowd.jpg).

NZ VRX Intake = TL/TW only right

NZ VRX Intake = TL/TW only right

Yes Dingers, you're spot-on.