Intake resonator

[Petrus]

The wubbah intake tract has a thing looking like an apendix on the side.
It is called a resonator.
I know these things have three, well 2,5 (possible) functions.
One is to tone down the inlet noise and the other is to tune the bouncing waves for the smoothest torque curve. The extra half is related to the latter as it can be a tuning device to avoid the MAF getting confused by a bouncing wave.

Does anyone know, has experienced, what the thing does on the 1ZZ??

[Dev]

 Although it is also used to tune resonance frequencies for sound reduction it is also thought its used for smoother power as the air flows into the plenum  but not for any kind of smooth air flow for the MAF sensor. The MAF sensor doesn't require anything but the calibration vanes that simulation a smaller tube to speed up the air velocity to get a correct reading. It has been thought that for most cars it is mainly for sound reduction. My other car has an aftermarket TRD option to eliminate the resonator pipe for better intake sound.
 
 For the 2ZZ according to the white papers they engineered the intake plenum for a sporty sound.

[jonbill]

It's a handy point to plug in an IAT downstream of the supercharger 😉

[Petrus]

My other car has an aftermarket TRD option to eliminate the resonator pipe for better intake sound.

Do you have a photo?

No vanes in mine anymore following Cap Weir´s mod ;-)

[Hammond]

I stumbled across this sometime ago and wondered if it is snake oil but maybe someone could shed some light on the theory behind it and if it is plausible that it could work?

siecle inlet response ring

[Dev]

No photo. I just know there is an option for it which I never would add since the car was made to be ultra quiet. TRD makes things that makes me scratch my head especially for a car that is meant for old people.

[Petrus]

I stumbled across this sometime ago and wondered if it is snake oil but maybe someone could shed some light on the theory behind it and if it is plausible that it could work?

siecle inlet response ring

This is a useless, performance redúcing gadget.

he sales argument borrows from the venturi effect.
A venturi is a small restrction in the inlet tract, which principle does mean an increased speed LOCALLY but not the average speed.

Because the gadget is a serious restriction, it will cause a pressure drop behind it, lowering the average speed, volume.

[Dev]

I stumbled across this sometime ago and wondered if it is snake oil but maybe someone could shed some light on the theory behind it and if it is plausible that it could work?

siecle inlet response ring

Interesting. Most of this stuff is usually snake oil but this actually might work but it is a backwards way of doing it. 

What this product is actually doing is reducing the tube diameter to speed up the airflow to the MAF sensor. This is similar to what the vanes in the OEM intake housing does. 
There is an aftermarket intake manufacture injen I think  that reduced the tube diameter before the MAF sensor so it will get a good reading and therefore have the correct engine response.

Where these products fail is causing a restriction in the intake path. The OEM vanes do not as they let the air flow though the sides and the divider speeds up the air simulating a smaller tube just before the MAF.

If someone made an 1ZZ air intake that had vanes that would solve all the problems in the world.

[Hammond]

I can understand the theory behind it and it's desired effect would be to increase low to medium speed torque response. If it does actually work though is another thing!

Thanks for the responses team. Always appreciated!

[Dev]

I cant find the Injen technology diagram but it works off the  same principle.  Injen says they tune the intake pipe to be narrower just before the MAF. 

Here is where they claim better performance using what they call MR technology.
 You cannot view this attachment.

 Although it is true that it will increase throttle response and torque its actually solving a problem that was created by  aftermarket intakes when the factory got it right. 
 However if someone is smart enough they can actually tune an intake to make more power which doesn't require a programable ECU. 
     

[Petrus]

I can understand the theory behind it and it's desired effect would be to increase low to medium speed torque response. If it does actually work though is another thing!

Oh it works; it increases the speed through the ring and close after.
As Dev observes it would mean an effect comparable to the vanes directly in front of the MAF.
The problem is that those vanes and MAF are calibrated to work together and the ring is not.
It would mean that the signal from the oxigen sensors would see the ECU adjust the mixture.
This would still most likely see the ignition timing shifted to ?
Again like with the vanes removes as per Cap Weir´s mod. This mod however is well researched by Cap and adjusted for by the raising of the MAF in combinattion with fitting larger injectors.
Also this MAF mod remóves a restriction which if anything improves flow.

[Dev]

I can understand the theory behind it and it's desired effect would be to increase low to medium speed torque response. If it does actually work though is another thing!

The problem is that those vanes and MAF are calibrated to work together and the ring is not.

 Although true that it is not calibrated it could still show an improvement in a aftermarket intake reason being that the aftermarket intake is also not calibrated to the MAF. If this device is positioned just before the MAF it could be beneficial because it will speed up the airflow to sensor wires.
 
With aftermarket air intakes what happens is  air flow speed is reduced to the MAF sensor wires which doesn't cool down enough. This will register less air volume when there is more more air. The 02 sensors sees the car run lean and starts adding fuel to compensate for a lean condition. Based on how the car handles this, it will not take advantage of the cars response and it will lose power.  This is why aftermarket air intakes make you lose power on the bottom end and reduce crisp throttle response. 

[Hammond]

siecle response ring website translated

Interesting read if you get the chance about the performance "gain"

[Dev]

siecle response ring website translated

Interesting read if you get the chance about the performance "gain"

I just read it. They are right in what effect it has but wrong on how it does it. I noticed that they want this device installed before the MAF as I suspected.

All this does is change the MAF reading for better throttle response at slower speeds but ends up sacrificing high rpms because it creates a restriction of the tube choking the airflow. They believe it speeds up the air into the intake plenum which produces power and that is where it's snake oil.   The better way is the vanes used in the OEM system because it doesn't obstruct the sides of the tube and maintains the intake diameter for both low and high speed performance.

[Petrus]

and that is where it's snake oil.   

Quite.
As it is too restrictive to be a true venturu not impeding the flow, it means the engine would need to suck harder to even get the sáme flow.
As it is there will be more of a pressure drop due to increased restriction than over the OEM vanes.
If one wants to improve flow of the n.a. 1ZZ, than Cap´s MAF mod is the only balanced change, taking out;




Back on topic, I have dug a bit further and conclude that the apendix is indeed a Helmholtz resonator

https://en.wikipedia.org/wiki/Helmholtz_resonance

to smooth peaks of inlet noise.

[Hammond]

Nice one team, good insight

[shnazzle]

... Been covered so many times on the forum hahaha. But was entertaining watching you guys go down the rabbit hole again.

Ye olde Helmholtz. Gonzo's beak. 
Someone did plug it up on a stock intake (as it can be removed) and did notice a difference. But when replacing wiht a smooth silicon pipe, the difference went away again.

[Petrus]

... Been covered so many times on the forum hahaha. But was entertaining watching you guys go down the rabbit hole again.

Ye olde Helmholtz. Gonzo's beak.
Someone did plug it up on a stock intake (as it can be removed) and did notice a difference. But when replacing wiht a smooth silicon pipe, the difference went away again.

Whether straight or bent makes no difference.

What was the difference?
10 hp more/less
10 dB more/less

[shnazzle]

... Been covered so many times on the forum hahaha. But was entertaining watching you guys go down the rabbit hole again.

Ye olde Helmholtz. Gonzo's beak.
Someone did plug it up on a stock intake (as it can be removed) and did notice a difference. But when replacing wiht a smooth silicon pipe, the difference went away again.

Whether straight or bent makes no difference.

What was the difference?
10 hp more/less
10 dB more/less

Who knows. It was all seat of pants who's got time to take a little tube off and put a car on a dyno or measure dbs? haha.