I used some basic parts from the plumbing section at Home Cheapo to bypass the Helmholz resonator on my car. I realize this does not add any power, it just makes the intake a bit more pronounced below 4000 rpms.

The rubber elbow needs to be trimmed on one end. For this I just used a utility knife and held the stock piece up to it and traced around it with a pen. The 1.5" rubber cap for the Helmholz resonator block off needed no modification at all and went on perfectly.
It was a bit tight getting the rubber elbow installed becasue it's so rigid. I left mine sitting in the sun for about an hour and that made it much easier to work with.
Total cost was exactly $9.07 and I reused the factory hoseclamps so now I have a couple extra

 

I had a 996 I bought the expensive pieces and always wondered what made them so expensive??? I guess it is all that Research and Development, the tuner researches a way to get your money and develops a Home Depot product and marks it up a bit....

 

No, they just make it out of molded red silicone and charge you a BIT more - $225
Hey, I've never been a big fan of cheap *** booty-fab jobs...but in this case it's pretty cut and dry what is being accomplished. The only difference is the quality of the parts I used. They seem very well made and are meant to used in commercial plumbing applications. My only concern is that high ambient engine compartment temps may cause the rubber to dry and crack over time. But, I wash my car frequently and in doing so always lift the engine cover to dry it off. I'll just make sure to keep an eye on the condition of the rubber elbow and if I do notice any cracking it'll get yanked.

 

That is a very good, simple solution . If the rubber quality is only half way decent, it should last for years.

I did my mod a little differently. I plugged up the resonator part of the factory air intake hose by using silicone mold material.
The plug is removable if desired since the silicone does not "bond " with the rubber, yet stays in place due to the elbow.
As you said, it does not affect performance in any way, but I love the deeper sound from the intake.

 

JCS - I'd like to see pics of your mod, that sounds interesting. However, I am a bit hesitant to introduce anything into the airway after the filter or MAF screen that is not held in place by something.
And you are right, the extra grunt from the intake is very nice.

 

Crod,thats awesome! Off to Home Depot.

 

What kind of silicone mold material? I have been waiting to do this mod but hesitant that I screw up by using wrong material.

 

this is awesome... plus it looks better than having a bright red hose and cap in there.

 

I used "One-to-One" liquid silicone rubber # 82083 sold by Micro-Mark

Tel: 1-800- 225-1066

Close off the resonator hose connection opening to the main air intake hose ( from inside the main intake with duct tape ) and pour the liquid silicone into the resonator hose.

It cures in less than 30 min. and remains flexible forever .
Just do not to fill the resonator hose all the way up (leave enough
space so that it can still be fit over the resonator box outlet connection)

Remember to remove the duct tape from inside the air hose.
( You definitely don't want it to get sucked into the engine ) Lol

The plug stays in place since it fills the elbow of the hose but it can be forced out if no longer wanted . Mine is in there for months now and it works great .

I do a lot of hobby work, so I use the mold material for other things.
It's about $ 30 for two lbs. and you won't need a lot of it .
So if you don't use it for anything else, the rubber elbow mentioned above will be cheaper .
There may be other solutions. After all, the only objective is to close the resonator outlet. If you put a STONG thin material (a Prophylactic should work pretty well Lol ) over the resonator box outlet and replace the hose back over it , it will do the same thing.

In any case, either method is A LOT cheaper than buying the rubber elbow
( cold air kit ) from Fabspeed for over $ 200 .

 

Has anyone just duct taped over the hemholz rez and installed the stock tubes back in place?

 

I did that first as a temp fix just to see if it did in fact make any difference in the sound. It did so I was happy. But, I was not happy when I inspected the condition of the tape after a full day of driving...
The dry, hot air that the tape is exposed to causes it to dry out and crack. I'd suggest anyone that has done this, check the condition of your tape. I could easily tell that after a few weeks the tape would begin to disintegrate and crack, causing small parts to get sucked into the motor - NO GOOD.

The tape is a good temp fix - temp as in one day or so. It's possible that I was using a low quality duct tape, but I guarantee you over time any tape will start to become dry and brittle.
Hope that helps

EDIT - Another benefit of replacing the stock accordian style tube is that the stock unit has ridges on the inside and most likely doesn't flow as well as the Fabspeed unit and the elbow I used which both have a nice smoothe finish on the inside. Fabspeed claims something like 20% better airflow but I have no clue how they measured that...

 

decent info thank you very much. I will do this soon. Does the engine sound change alot?

 

I would say you get a "deeper" sound and definitely a bit louder.
Similar to a less restrictive, mild performance muffler.
Why don't you follow Crods advice above?
Temporarily put some duct tape or STRONG thin plastic material over the resonator outlet . If you like the result, proceed with the permanent solution.

Have fun.

 

i was so inspired by the ingenuity of this mod i went and did it today. but it didnt cost me 9 dollars it cost me 12!! i think i got ripped off at the durham home depot but oh well.

anyways i found that its easiest to get the rubber elbow fitted to the airbox first using your hand to stretch the elbow from the inside, tighten, then use ur finger to ease the other side over the throttle body. theres more room to get your hand around the throttle body from the outside than on the airbox side.

 

You should not use platinum or tin curing molding silicone anywhere near the intake manifold, your O2 sensors are not compatible with it and they will fail.