PontiacBonnevilleClub.com

I'm working on a custom air box. What is this hose that runs from the top of the air box down under the trans and is it okay if I delete it?

Secondary A.I.R.

In a nutshell, all the secondary A.I.R. system does is inject air into the airstream to help light off catalyst, usually on Open loop startup. The PCM commands it off usually after 240 seconds or once the PCM goes into Closed Loop operation, whichever comes first. Some vehicles are very sensitive to it, others aren't. This is the one car where for me that wasn't sensitive to it, so once I made my own CAI, I never ever used it. It just sat there blowing air into the air until the PCM shut it off.

If you're looking to produce this, I would make an attempt to incorporate the inlet for it. Otherwise if this is just for personal, I wouldn't worry about it.

Any pics of your air box?
I'm planning on deleting he cat too

I never took pics. I also didn't make a box, I just snug fit a bend and a filter through the hole behind the headlight. If you don't keep hot air away from it, you will get lean codes in the summer.

what size filter? 4x4 or 6x4?

Something I had in a box from the umpteen CAI's I've had in other vehicles over the years. It was a frankenstein CAI. It had GTO CAI parts, Grand Prix CAI parts, some random silicone tubing and Spectre tubing, and a filter. The GTO's Plumbing was 4" diameter, so other than the bend I had to make behind the headlight, it was all consistent sized, so it would've been 4" ID filter opening.

How long was the filter? I feel like I could fit a 4 inch easily but the engine seems to warrant a 6. Which would seem to mean making a 90* elbow behind the headlight to mount it vertically

Honestly, I don't recall.

Or you could just buy mine!?
http://www.pontiacbonnevilleclub.com/fo ... 38530.html

does it fit down behind the headlight into the fender well or is it exposed to the engine bay?

Sorry, I have a plethora of filters laying around in varying sizes, so I probably just grabbed one that fit and stuck it on. I may have actually ramped down the diameter to say 3" or 3.5" before the bend down behind the headlight to facilitate the 90* angle needed and then run another straight piece and then fit the corresponding size filter I had laying around.

Again, this was a Frankenstein setup. I have like three boxes of spare plumbing, clamps, hoses, PVC parts, and filters, and I just made stuff work. I did not run it to the fender like many here and many of the aftermarket kits. I ran it out behind the headlight and down.

Mine is completely behind the bumper away from any engine bay heat. I used 4" aluminum pipe.