Cold Airbox Mod - Pontiac GTO Forum
User Tag List

Reply
 
LinkBack Thread Tools Display Modes
post #1 of 37 (permalink) Old 11-04-2005, 07:12 PM Thread Starter
Former Moderator
 
svede1212's Avatar
 
Join Date: Oct 2005
Location: Grand Rapids, Michigan
Posts: 4,081
Mentioned: 0 Post(s)
Tagged: 1 Thread(s)
Quoted: 25 Post(s)
Garage
Cold Airbox Mod

This mod lacks the bling of some of the commercial "C"AIs but from what i observed of them they lacked the "cold" part. they all relied on the stock holes in by the radiator cover and the two small holes below the airbox to bring in air. the kay-n-en and that lincoln feller also both had gaps where they could pull in engine bay air when the stock holes couldn't keep up (there's 12 sq inches of cross sectional area in the tube by the TB. i couldn't find that much in total from the stock holes). i have seen many discussions on many boards and claims by manufacturers about horse power increases, whether thru dynos, seat-of-the-pants, drag times, etc. the tests and measurements to back up those claims and the things that are lacking are the "Air Intake Temperature" (AIT) and the pressure drop at the throttle body (TB). the temp can be monitored thru the AIT sensor and the pressure drop can be measured with a manometer at the TB between stock and various other setups. these are the only things that matter and yet not one manufacturer has ever posted such results. in my stock '04 the restrictions were at the Mass Air Flow (MAF) tube and the MAF sensor. the tube on the '04 constricts down in a small square opening plus the accordian creates a whole bunch of turlulence/resistance. i replaced the tube with a 4" ID smooth bore JHP MAF tube. the MAF sensor may get removed if i go to a speed density tune down the road. i replaced the stock panel with a K&N after the stock had 12,000 on it. i figured the long term cost will be less with a reuseable. in actual manometer testing the K&N panel has a slightly lower resistance but the difference between stock, K&N and no filter at all is negliable. anyways here's what i did to really bring in cold outside air. at the strip i really pull hard in the top end with a best trap of 105.99 MPH with all else being stock except for the shifter.

i drilled a hole where the smaller hole below the stock box was. i used a 3" hole saw and had to wedge a board underneath so the pilot bit could center on something. it intersected with the elongated hole that was already there and i used tin snips to cut off the triangle that was left to make an even bigger hole. that's the garage floor underneath.



Then I hacked the inlet "box". it had a baffle that partly blocked the two lower holes. i used foam tape to insulate everything from engine bay heat.




inlet "box" insulated



inlet "box" in car with the hole down below




Modded and insulated filter box. Note i cut that irritating anchor tab off of the front




This shows the insulated IAT sensor




and the finished "snug-as-a-bug" installation



2004 Blk/Rd M6
6.3 litre LS1

Built and tuned by svede

Last edited by svede1212; 11-04-2005 at 07:16 PM.
svede1212 is offline  
Sponsored Links
Advertisement
 
post #2 of 37 (permalink) Old 11-05-2005, 06:56 AM
 
Join Date: Nov 2004
Posts: 267
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
nice job !!..i will be doing something similar, how much was the aftermarket intake tube ?? and were did you get it....
flht3 is offline  
post #3 of 37 (permalink) Old 11-05-2005, 07:08 AM
 
fergyflyer's Avatar
 
Join Date: Apr 2005
Location: Eustis Fl.
Posts: 3,445
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I did almost the exact same thing. I like the fact that it retains stock appearance. Before doing it in the heat of the Florida summer, I was running 13.8-14.2 at 103-104. After doing it I ran a couple 13.2 at 107, but the majority were at 13.4-13.6 with nearly identical weather conditions. I also enlarged the hole at the bottom of the airbox and it can pull air from below. I then used weather stripping to block some air from the engine compartment.
fergyflyer is offline  
 
post #4 of 37 (permalink) Old 11-05-2005, 10:17 AM Thread Starter
Former Moderator
 
svede1212's Avatar
 
Join Date: Oct 2005
Location: Grand Rapids, Michigan
Posts: 4,081
Mentioned: 0 Post(s)
Tagged: 1 Thread(s)
Quoted: 25 Post(s)
Garage
thanks. i've been running 13.3 to 13.5 with it. with my trap speeds i know i can get a lot lower if i can ever hook up. DRs are a must. the rears are getting thin so it will be my first purchase next spring. i used the tape to seal everywhere around the box so it can only pull from outside. i had extra tape left over so i taped up the MAF tube. i don't know if it will stay on in the heat of summer (it's rated for 180*) but if it doesn't work i'll glue it with something else. insulating the AIT sensor is a very good idea. it is in a spot that gets heat from the radiator and i think the insulation will prevent heat soak. the tube i got from JHP (at www.JHP.com). it's an aussie company. eMail them for a price. they don't post prices on their page due to fluxuating exchange rates. they are a good company to deal with tho. i should know what i paid but i don't . they gave me a good price because i bought my GMM rip shifter from them at the same time (the best first purchase you can make).

2004 Blk/Rd M6
6.3 litre LS1

Built and tuned by svede

Last edited by svede1212; 11-05-2005 at 10:28 AM.
svede1212 is offline  
post #5 of 37 (permalink) Old 11-05-2005, 05:42 PM
 
rushhour's Avatar
 
Join Date: Aug 2004
Posts: 97
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Not sure if you need to go that big of a hole - but it can't hurt.

The insulator is a great idea.

I am have been the 2 hole Monaro CAI also (see my pictures) for a year or so now - it works great. Best time so far with a 04 A4 is 13.364, best top end 105.17. I use the 300 KW HSV tube in conjunction with the modified air box.

I agree though - there are a lot better/cheaper ways of getting the car to breath then the "CAI" kits on the market. The Aussies have been doing this for years.

2004 Black, A4, (aka the Black Demon)
390ci AES low compression
PB 1.611, 11.732 @ 115.22, DA +1,973 @ 4,005 lbs
1.566, 11.585 @ 116.22, DA +960 @ 4,010 lbs (Nasty Headwind)
1.538, 11.352 @ 119.16, DA -2,340 @ 3,960 lbs
rushhour is offline  
post #6 of 37 (permalink) Old 11-05-2005, 06:08 PM Thread Starter
Former Moderator
 
svede1212's Avatar
 
Join Date: Oct 2005
Location: Grand Rapids, Michigan
Posts: 4,081
Mentioned: 0 Post(s)
Tagged: 1 Thread(s)
Quoted: 25 Post(s)
Garage
yeah, i wanted to make sure i had in excess of 12 sq inches of opening to the outside. as i stated, that's the cross-sectional area of the MAF tube. also as i stated i think the aftermarket CAIs are at best as good as my mod and more probably not quite as good due to the limitied amount of outside air they pull in. the "dyno tests" are the biggest hoot. remember folks the only things that matter are pressure drops and temperatures. i challenge any CAI manufacturer to publish those results.

2004 Blk/Rd M6
6.3 litre LS1

Built and tuned by svede
svede1212 is offline  
post #7 of 37 (permalink) Old 11-05-2005, 06:51 PM
 
Holden's Avatar
 
Join Date: Sep 2005
Posts: 344
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Good post im on board!!! Like JHP also. Thanx for PICs.
Holden is offline  
post #8 of 37 (permalink) Old 11-05-2005, 06:52 PM
Super Moderator
 
6QTS11OZ's Avatar
 
Join Date: Mar 2005
Location: Where the women are scarce and the sheep are scared. So. Cali
Posts: 2,639
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Quote:
Originally Posted by svede1212
yeah, i wanted to make sure i had in excess of 12 sq inches of opening to the outside. as i stated, that's the cross-sectional area of the MAF tube. also as i stated i think the aftermarket CAIs are at best as good as my mod and more probably not quite as good due to the limitied amount of outside air they pull in. the "dyno tests" are the biggest hoot. remember folks the only things that matter are pressure drops and temperatures. i challenge any CAI manufacturer to publish those results.
I did similar kind of mods to my air box too before I got my LPE CAI. Throttle response is much more noticeable with the CAI though. But seriously, you don't think a major CAI manufacturer would waste their time challenging something as insignificant as this do you?

~I'm ya huckleberry~
~516rwhp/500rwtq~

http://www.youtube.com/watch?v=yC11NCGTEvI
6QTS11OZ is offline  
post #9 of 37 (permalink) Old 11-06-2005, 12:27 AM Thread Starter
Former Moderator
 
svede1212's Avatar
 
Join Date: Oct 2005
Location: Grand Rapids, Michigan
Posts: 4,081
Mentioned: 0 Post(s)
Tagged: 1 Thread(s)
Quoted: 25 Post(s)
Garage
no because then they wouldn't sell their over priced stuff. "noticing" isn't very scientific. the insignificance is that they couldn't post anything that would make you part with your money besides the bling factor. i think the noise they make is the seat-of-the-pants that's noticed. before and after dyno runs are taken right at install and not after the comp has had time to adjust after 100 miles. has anyone looked at their "CAI" and looked to see where the "Cold" air it is taking in is coming from? are there extra areas opened up? i just saw the same openings that were there with the stock set up. does it chill the air somehow? do they insulate the AIT sensor? seriously the parts for them are the smoother tube (on an '04, not even that on an '05) and an oversized air filter, the major "restriction" in the path is not the air filter but the MAF sensor. tests have been done with stock filter, K&N and no filter. the K&N is almost like no filter. the air box on the stock setup is not sealed well against engine bay air but neither are the aftermarket ones. the ones i looked at had small gaps by their sides. you can seal the stock one a lot cheaper. with the lincoln feller you do get that cool little window tho. i think we should all get them because everybody's doing it. if you have money to burn, follow the got to have it factor and like bling, go for it. i'm saving the money i spend on my car on something that makes it go faster.

2004 Blk/Rd M6
6.3 litre LS1

Built and tuned by svede

Last edited by svede1212; 11-06-2005 at 08:45 AM.
svede1212 is offline  
post #10 of 37 (permalink) Old 11-06-2005, 08:53 AM
Super Moderator
 
6QTS11OZ's Avatar
 
Join Date: Mar 2005
Location: Where the women are scarce and the sheep are scared. So. Cali
Posts: 2,639
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Quote:
Originally Posted by svede1212
no because then they wouldn't sell their over priced stuff. "noticing" isn't very scientific
I don't think that most are worried about theories of operation or scientific explanations. Who cares how it works? I just want it to work. When someone make comments on their installed performance parts, mods, or whatever the first thing they say is they "noticed" or didn't "notice" any gains. Not, "Oh I wonder if the molecular bonding was adequately rotating at the projected force from turbulent input.... Why make changes if you're not expecting to "notice" any improvements? But as always, to each his own.

~I'm ya huckleberry~
~516rwhp/500rwtq~

http://www.youtube.com/watch?v=yC11NCGTEvI
6QTS11OZ is offline  
Sponsored Links
Advertisement
 
Reply

  Pontiac GTO Forum > The 2004-2006 GTO > Service, Maintenance and Technical Discussion

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Pontiac GTO Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome