Removed Intake Muffler, Sounds great!
 

Hey guys, My saturday project was to remove the sound muffler from the end of the intake tube near the throttle body.

It sounds GREAT! Since i already Desnorkeled, i already get that great intake growl from 4800 rpms and up but now with the intake muffler removed, i get this great deep growl at lower rpms that i can sometimes feel in my chest and back which starts at a suprizingly low 2800 rpms.

Since i couldnt find a plug to cap off the intake tube where the muffler once connected to, I bought a 60 second epoxy from autozone, mixed that in a plastic deposible cup which i cut 2/3rd's of its height away and plunged the portal where the muffler once attached into the cup full of epoxy and let it set for 3 minutes then pulled the cup off and let it dry for about 20 more minutes before installing... If you want more growl and dont want to buy a $300+ intake which is basically a peice of tube, then i recommend this mod for you!

Sweet, lol how do i do this mod?, can you make a dyi, does it cause a Cel?

thanks

Since i dont have a camera on me ill explain what you need to do.

Parts & Supplies
-8mm socket
-10mm socket
-Ratchet + extension
-Pliers
-Plastic disposible cup
-60 second quick drying Epoxy

Instructions

1) Place top in service mode and remove engine cover.

2) Uplug & Remove MAF

3) Remove hose clamps that hold intake tube to airbox and throttle body.

4) Remove 10mm bolt that holds intake muffler to engine lift bracket.

5) Now, the tricky part... Removing the Intake tube, It wont just lift outta there, the muffler is so bulky that it'll prevent it from coming out UNLESS you pinch the clamp that holds the muffler to the intake tube while you pull the intake tube out.... This will cause the muffler to slip off the intake tube thus alowing the intake to come out of the engine bay, then you can remove the muffler from the engine bay.

6) Now clean the inner and outter surfaces of the neck of the intake where teh muffler attached.

7) Get a plastic disposible Dixie or similar cup and chop about 2/3rd's of its hieght away.

8) Now start mixing your epoxy inside the shortened cup for about 15 seconds with a stick or similar device

9) Now plunge the intake tube's muffler neck into the cup of epoxy and let it set for about 3 muntes or until cured then let it sit for 15 more minutes before reinstalling the intake tube.

10) Now reinstall everything (minus the intake muffler) in reverse order


Alittle FYI, this was done to a 1997 boxster and some newer boxsters (E-gas versions) may not be able to do this mod cause of a redesign in the intake tube. In newer boxsters the intake muffler is integrated into the intake tube and isnt removable.

DISCLAIMER This forum nor I are responsible for any malfuntions, mechanical failures and deaths which may occur by doing this mod. Mod/Hack at your own risk.

Oh yeah, as for check engine lights, i dont know cause i already have one due to a secondary air injection gremlin that i have yet to fix but ill recheck the computer for any new codes later today.

interesting! now the part that i don't understand. the plastic cup and epoxy....am i glueing the cup somewhere...kind of confused. circular cap/plug doesn't help. if you could please explain this further. or pics would be amazing!!

i'm jealous i want to try tooo!!

i'm fairly good with my hands, so if you could make me understand in a better way.

I have the True Flow intake which also deletes this small muffler as you call it. No cell lights will come on. Its really nothing more than a silencer along the intake tube. I think if you look at Home Depot you should be able to find a circular cap/plug for that size hole. It will make your car growl more. Here is the area he is talking about. It looks like a small box that is connected to the intake tube. Inside of it you will find a white foam silencer. There really is no need for this part other than to quite down the noise level. In fact, this area being removed should provide better air flow. I would suggest buying a 90 degree elbow bend plastic tube from Pepboys and making your own intake tube. It's pretty easy. :D This will delete number 6, 7 & 8.
http://i5.photobucket.com/albums/y15...h/Picture1.jpg

thank you for the picture. can't i leave it open, why even glue a cup to the end, if it's open anyways. does this make sense. if i get an elblow put on, i am still leaving it open. or am i missing a step. i am pulling the silencer out of the box, so the box is now empty. will i be putting the box back also. dumb questions...i guess when i open, i should be able to figure it out better.

No. You are right. If you buy an elbow silicone cupler and also buy an extra clamp, there is no hole left and no need for messing with epoxy or anything like that. Look at this picture. Simply cut the tube at the ribbed part at the end going towards the throtle body and add the new elbow at that end with the new clamp.
http://i5.photobucket.com/albums/y15...Picture2-1.jpg

If you buy a silicone elbow and an extra metal clamp, after your install it should look like this.
http://i5.photobucket.com/albums/y15...h/Picture3.jpg

Most aftermarket cold air intakes kit like the Evo and Trueflow come with these parts deleting the same box alone the intake tube. This is a very simple and inexpensive way to ad a more true air flow pathway to the T.B. :cheers:

Technically, it's called a resonator. The resonator IS the box, the foam inside is a secondary noise canceling measure. It's typical on most intake tracts. It's function is to capture pressure (sound) waves, bounce them around, and send them back up into the intake plenum 180 degrees out of phase, thus canceling some of the noises coming through the throttle body. It's like a passive version of those Bose noise canceling headphones.

It doesn't effect flow, so removing it will not change the performance of the engine. Removing it can't throw the check engine light.

which website gives the exploded image views?

Thanks
Nick

None that I know of. I've been making these in Photoshop from the PDF manual that I have on my computer.

ahhh beautiful. this helps. thank you so much. i shall try this mod.

okay you've helped out this much...i might as well ask one last question.
this new silicone elbow, what is the diameter? what size am i looking for approx!

What my directions say todo is to remove and discard part number 6, 7 & 8 completely...
The Epoxy in the cup will be jammed onto the opening circled in the picture... However once the epoxy is cured abit and almost solid, you peal the 2/3rd size cup off and the epoxy should stay behind stuck onto the opening circled in red.
http://i10.photobucket.com/albums/a1...icture1111.jpg

Is this before or after the air filter? If after than I would be wary of your epoxy plug. If, over time it hardens and cracks, little chunks of epoxy could start heading towards the intake valves. Ugliness and tears would ensue. I think using the elbow makes a lot more sense.

Regards,
Alan

Hmmm, i dont know... i dont see that epoxy cracking, i mean nothing touches it, no moving parts either and rated up 2500 psi before point of failure. I can see an airfilter deteriating sooner than the chunk of epoxy but your right about the elbow... does seem safer, But imma stick with the stock elbow its hard inner surface will probably help echo the intake noise alittle better than a softer sylicone elbow.

Heat + vibration + pressure from a hose clamp (if you're using one). I'd be looking for a molded plug.

CJ,
Am I missing something here? Is the resonance box just a muffler to reduce intake noise or is it an important part of the factory tuned intake. With a properly tuned intake, sonic waves from the intake pulse combine with airflow to force charge the cylinders as much as 125% of airflow alone. Porsche has been tuning this for a long time to give us better top end power and that nice big fat torque curve that gets us out of corners quickly.

I don't know the answer to this, just raising the question. Tuning an intake/exhaust is a lot more like tuning a musical instrument than we realize. It would be disappointing to remove the res. box and get a narrowing of the torque curve and lose 10hp in the process. Faster good, Slower bad! Any Porsche racing techs in the know on this?

I'm with Topless - obviously missing something here. How does plugging a hole allow more sound to get out?.

Also agree that the airflow characteristics are likely altered. For the better? Worse? That I cannot say. But, the OEM piece is certainly not merely an afterthought by Porsche.

I have a car going to dyno to test some different mufflers/straight pipes. I'll test this also with a stock muffler in place.

Based on previous experience with Porsche intake manifolds.. I'm betting this is a muffler. Any kind of overlap in the valves will produce intake noise.


B

Well i havent felt a decrease in power at all on my butt dyno but I do feel like ive gotten more power, especially in first gear... this could be placibo effect but if anything, i would say i had a gain.

Butt dyno would be off on the car I'm dyno'ing :) Removed upwards of 500lbs out it.. LOL



B

How in the heck did you remove that much weight? It must be just a shell.

You could call it that :) Another Boxster Spec car being built :) which is why I'll be dyno'ing different exhaust combo's. Straight pipes for large tracks and *some* kind of restriction for short tracks like Laguna or Sears.

http://www.boxsterspec.com/uploads/m...8492_thumb.jpg



B

Dang, what do you do for a speedo and Tach?

you should caption that picture with "Still havent found where that rattle is coming from"

It will have a dash :) (stock) one. To get the Heat/Ac unit out of the car.. pull the dash. The roll cage will pass through the dash.

Heat/Ac unit:

http://www.boxsterspec.com/uploads/m...8479_thumb.jpg



B

Are you going to do anything fancey to the dash now that its out like, cover it in leather or alcantera with body color'd stitching?

Rattle.. :LOL:

I drove it Sunday night.. it is actually VERY quiet for having ZERO sound deadening in the chassis.

http://www.boxsterspec.com/uploads/m...4244_thumb.jpg


http://www.boxsterspec.com/uploads/m...4268_thumb.jpg


B

For those of you following along at home.. this is what we are talking about:

http://www.boxsterspec.com/uploads/m...5033_thumb.jpg

Something else of note that we do to these cars: we install 996/BoxsterS oil coolers. They are nearly double the capacity.

B

Oil cooler differences: Stock 2.5 on left..

http://www.boxsterspec.com/uploads/m...9102_thumb.jpg


B

Oh man, you have to admire the engineering behind the boxster to be quiet without all the sound deading.

Is that oil cooler your talking about the oil cooler below the intake manifold?

Correct on the oil cooler. You can see it below the intake in the pic above.

The X51 oil cooler is nearly double the size of the BoxsterS cooler!!!


http://www.boxsterspec.com/uploads/m...1204146571.jpg


B

Interesting, Is there enough room under the manifold to fit the X51 oil cooler or would that be over kill for a boxster?

I don't believe it will fit :( The main difference between the Boxster and 996/997 intakes: the 996/997 is TALLER (they have more room) The runners are longer before it becomes "plenum" so they have more room to stack stuff on the top of the engine.

Porsche has a lot of engineers.. I only add the larger coolers to the early cars that will be tracked or DE'd.


B

Good deal, well let us know what happens with your dyno results.

This little box is most likely for noise abatement alone. It doesn't have the volume to make much of an impact on the pressure waves of the intake flow.

Here is what Porsche says about their tuned intake:

"The Boxster inherits its twin-resonance air induction system from the 911
Carrera. The system acts as a “resonance supercharger,” allowing the engine
to draw from higher velocity airflow at certain engine speeds. A crossover pipe
connects the individual air collector/resonance chambers for each cylinder bank.
A flap in the pipe remains closed from idle to about 3,100 rpm. When it opens,
each cylinder bank can draw from airflow “excited” by the resonance created by
alternating induction between all six cylinders. In essence, “dual resonance”
creates two induction paths for each cylinder. Below 3,000 rpm, the cylinders
draw air from a “short” path. From 3,000 rpm to about 5,100 rpm – when the
resonance flap opens – the cylinders draw from a long intake path, which
boosts torque. Above 5,100 rpm, the flap again closes to allow the cylinders
to draw intake air from a shorter intake path to boost horsepower at higher
engine speeds."

They don't address that little res. box specifically but others in this forum have removed it, dynoed and lost torque and HP. I gotta believe it is a small part of their tuned intake system. The GT3RS has 3 res. chambers. Somebody thinks they are important. It's sort of like tuning a subwoofer cabinet. You adjust cabinet volume, dampening and port size to maximize certain desired frequencies (or RPM's).

Does this make any sense to anyone or am I just a lone voice deep in left field??

The intake plenums and the tubes connecting them are definitely meant to help intake charging, both by changing tract length and pressure wave control. The little box doesn't have the same function.

Are you saying that other people on this forum have removed the little box and found a power reduction?

'Am I missing something here? Is the resonance box just a muffler to reduce intake noise or is it an important part of the factory tuned intake. With a properly tuned intake, sonic waves from the intake pulse combine with airflow to force charge the cylinders as much as 125% of airflow alone. Porsche has been tuning this for a long time to give us better top end power and that nice big fat torque curve that gets us out of corners quickly.

I don't know the answer to this, just raising the question. Tuning an intake/exhaust is a lot more like tuning a musical instrument than we realize. It would be disappointing to remove the res. box and get a narrowing of the torque curve and lose 10hp in the process. Faster good, Slower bad! Any Porsche racing techs in the know on this? '


I added a TTP intake which effectively deleted the muffler, at the same time I had the car chipped, so I dont know what effect the change in the intake alone had on the cars performance. When I dynoed it after the intake and chip combination, I picked up about 20hp, then picked up another few with headers on my 2.7. I have a photo of the intake tube at my website below my signature.

Ed

:cheers: