Bellows tube; a few thoughts.

dinetuner · Post by **dinetuner** » Wed Jun 21, 2006 4:59 pm

*shakes head*

bigbird · Post by **bigbird** » Wed Jun 21, 2006 8:29 pm

well here is my cheap replacement.....

I'm not sure if it helped or not. The old butt dyno is not so reliable!

flhmfd · Post by **flhmfd** » Sun Jul 23, 2006 1:04 pm

bigbird wrote:well here is my cheap replacement.....
I'm not sure if it helped or not. The old butt dyno is not so reliable!

what exactly did you use to replace the bellows, my intake should be here soon and it doesn't have the replacement...so i need to build one...

what does everyone use?

BlackRoseRacing · Post by **BlackRoseRacing** » Sun Jul 23, 2006 1:58 pm

The bellows tube IS designed to provide a flexable intake track into the engine, thats why its designed the way it is. Replacing it with a solid piece helps airflow but you better have some type of flexable point since OE the TB are mounted solid away from the motor Vs directly attached. You WILL need some type of flex.
As for the bellows tube expanding and contracting, the tube will retain its normal size when the throttle is open and there is no vacuum, it will try to contract when there is vacuum....

flhmfd · Post by **flhmfd** » Sun Jul 23, 2006 4:15 pm

i have energy motor mounts (not installed yet) so would that eliminate SOME of the need for it needing to be flexable?

will i gain any power from replacing it?

and what could i use?

BlackRoseRacing · Post by **BlackRoseRacing** » Sun Jul 23, 2006 4:20 pm

people claim there are gains by replacing the bellow's tube but there are NO documented or dyno reults posted to back it up. Just keep your tube inless you HAVE to replace it

BlackMagic · Post by **BlackMagic** » Thu Sep 28, 2006 2:14 pm

Please accept my sincere appologies, but I had to bring this really old topic back. It's very interesting and I was bored to DEATH.

The stock plastic bellows tube is flexable but you won't have any problem in that department. Why? Because any good intake would come with a mount that allows a little bit of movement. Right? I have the AEM CAI and it came with a sweet wittle mount which has a rubber bushing. Infact, AEM even says "If you don't install the intake with the rubber bushing we are not responsable for any damage to the intake.", or something like that (should NOT have used quotes but oh well I like typing more than hitting that horrid backspace key).

As far as the increase or decrease in HP... I'm seeing people saying that the stock tube is better and others saying smooth bores are better.

I love small disagreements. I would definatly like to see a dyno sheet showing the difference. Even if it's only 1HP more or less, it still has an affect.

Oh crap I'm bored again...

I promise I'll take care of my bordom some other way if you don't like the idea of me bringing this back!

C-ya, would NOT wanna be ya... Unless of course you drive a tottaly pimped to the max show and go neon that I am jealous of.

atom · Post by **atom** » Thu Sep 28, 2006 3:59 pm

You have me interested in this topic all over again. I also now retract my original statement. I guess with injectors, the fuel is sprayed in rather then dumped in so turbulent air does not help. I am thinking of replacing my bellows tube, I am back to the stock air box and I have to say, my car seems a lot lot slower. Maybe it can help!

BlackMagic · Post by **BlackMagic** » Fri Sep 29, 2006 7:28 pm

Your car seems slower? I could barely even notice the difference after doing the whole cai

OB · Post by OB » Sat Sep 30, 2006 12:53 am

car should actually feel a bit stronger in the low range w/o the CAI. However, the higher range loses some ponies, especially around 4000 rpm, where the stock box has been known to cause a bog, wheras the CAI will usually cause the car to actually pick up and go.

atom · Post by **atom** » Sat Sep 30, 2006 8:21 am

Sorry I should have specified, I am back to the stock bellows tube, stock air box, and no piping that goes into the fenderwell. Hot air intake.

04solaryellow · Post by **04solaryellow** » Mon Oct 02, 2006 5:13 pm

OK, I have to stick my finger in the pie...I replaced the bellows pipe with a hard tube,and for now made a bracket to hold the TB,with a K&N filter on the TB. My question is,will changing the length of the tube affect preformance one way or another?

BlackRoseRacing · Post by **BlackRoseRacing** » Mon Oct 02, 2006 6:30 pm

No one has really tested that theory either...

CA180 · Post by **CA180** » Mon Oct 02, 2006 6:37 pm

I think i asked that question not too long ago... no one commented. I havent tried any test to see if I can feel any difference.

anomalous0 · Post by **anomalous0** » Thu Nov 02, 2006 5:01 am

if you are using the replacement tube....then it will have a slightly larger I.D. than the stock bellows tube (at least my homemade 2.5" one does and all the pics I've seen do too as they will fit over a 60mm TB.) Hypothetically (and this may not be true due to the manifold inlet being restrictive or other stuff.) Hypothetically, replacing the stock bellows tube with a smoother one with a larger I.D. would effectively increase your plenum volume, maybe at most by 1 %. A larger plenum would be best for high RPMs, since air would just "pool" there at low RPMs. So with the effective plenum volume being slightly larger.....your HP at high RPMs might go up.....maybe by a little less than 1%......or 1 HP

Add in the fact that it decreases turbulence in the airflow......and it's not hard to imagine a gain so small that it'd disappear from one dyno run to the next....though still present