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Discussion Starter #1
OK, Gary from Compass MotorSports is probably never going to mass produce his wonderful CAI intake. So, I have decided to try and make my own. Yes Cobb, PDM, GanzFlow and etc. are all nice but I want something different.

I have a 1999 2.5RS auto. My idea goes something like this: I figure the "torque box" is around 3 to 4 liters in size. I believe the elbow coming out the sie of the box is about 1.8" to 2" in diameter. The MAF is almost 3" in diameter. The filter box just plain bites. The MAF needs good air velocity to read correctly. The cooler and faster the charge the better but up to a point.

So...I was thinking about finding a fiberglass or PVC 3 - 4 liter bottle and attaching a 2.5" elbow to the side and a 3" tube to the middle for the throttle body. Then running a PVC 2.5" tube to a conical air filter housed in a Cold Air Box.

My belief is that this will keep the torque I need for my auto, yet smoot out the air flow considerably and keep the velocity of the airflow within spec's. If done right it will cost less than $100 and should provide a gain close to or better than Cobb's and still keep the torque. Actually I'm looking for the kind of HP and TQ made by Gary's intake. :D

Anybody have any criticisms on this type of setup? What are the good and bads? Where the heck can I find a 3 to 4 liter fiberglass or PVC bottle. Should be kind of shaped like a fire extinguisher. Or am I smoking to much crack and need to come down? :D
 

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99 2.5 RS-T
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Actually, that idea has some merrit. Id suggest look at Summit Racing, Racerswholesale, etc for catch cans. You probably wont find fiberglass (unless you DIY) and PVC, doubt it... probably find ABS (or similar) plastic.
 

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Discussion Starter #3
Boy,

That's a great tip. Thanks! I have both the Jegs and Summit Catalog's so I'll take a look tonight. I think I remember them having some pretty sizeable catch and cooling cans.
 

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99 2.5 RS-T
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May also want to try a local motorcycle shop, they often have fuel tanks for sale so customers can take 100/104 octane home with them.
 

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Discussion Starter #5
Well, catch cans won't work. To small. Usually around 1qt. But, I did find Jr. Dragsters fuel cells and Summit Racing Vacuum Canisters. Also have 45deg. fuel inlets. This just might work. Gotta do some measuring on the stock TQ box this weekend.

I will do this. It's just going to take some time. Having ran a normal J-tube intake it really killed my low end.
 

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2001 Silverthorn Coupe
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PVC will melt, or at least give off noxious gasses that would probably not be a good idea to feed your engine.

ABS should be alright. Fiberglass would be best in my opinion. Aluminum would be super cool, but not in a temperature sense.

Have you seen the intake that draws from the wiper well? That would be a ram air set up (drawing air from the high pressure zone at the base of teh windshield)?

cheeRS,

Greg
 

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Discussion Starter #7
Unfortunately I have a MAF so drawing from the wiper well would be tough but not impossible.

The more I think about this the harder this type of intake is to make. Fiberglass would be the way to go but I believe that it would take a lot of it to make a box as big as ours. Plus I just don't have the skills to do it.

So, I've decided to try and make a Cobb Clone and see what that does to my low end.
 

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Discussion Starter #9
Thanks Dave! I forgot about those. I wonder how they are doing? They never went into great detail about how the power felt.

I went ahead and bought a used torque box from a 2000. I'll try what they did and see how it feels. At first I'm just going to use the stock filter box at the fender until I can figure out how to put a cone filter on and still keep the cold air. I could put the filter in the fender but that is a real pain. And I'm not sure how I could make a plexiglass/lexan shield or box.

I have the JCS torque chip and am using a stock intake right now. It's definitely not the ideal setup for getting full use out of that chip dealy.

Shawn
 

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The power improvement is quite noticable as well as the sound! I haven't changed my exhaust yet or done any of the fueling and ECU upgrades (waiting on DNT's SC kit). The guys at the dealership thought my intake was quite innovative as well as the guys at the SMOG check station! My wife has an 02 WRX and she likes my RS for 'hot roddin' around town because its quicker off the line now!

:sunny:
 

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Discussion Starter #11
My wife has an 02 WRX and she likes my RS for 'hot roddin' around town because its quicker off the line now!
WooHoo! My car (automatic) was a real dog with the JC Sports J-tube on it. It would fall flat on it's face on take off. Plus it had this really "raspy" sound that I didn't like. I could hear it over my Borla headers and Stromung exhast it was that loud.

How about a consensus on what the fins do inside the box. Are they there for strength or to break up the air flow and make it "swirly" for better fuel economy?
 

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The fins are for structural support and directing the air towards the air filter. Trimming back the fins near the intake port does not affect the air flow. Taper the fins so they are somewhat even from right to left accross the back of the box. The air box drasticly improves the low end torque. I suspect that the fins also break up the sound coming from the intake runner inside of the box. With out the box this sound (raspy as you call it) would reverberate inside of the J tube...

:sunny:
 

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The two threads linked above don't seem to exist anymore. Did we lose them during the move this year? I was really hoping to read up on them as I have a 98 and want to make my own intake and keep the plenum as part of it.

If anybody has any info on this I would appreciate it.
 

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'00 2.5RS coupe (9/01-1/04)
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Here's a pic of mine, even though you didn't ask for it. MY98 legacy airbox, w/ custom pipe and K&N filter kinda ghetto-rigged on there.
 

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Thanks for the heads up - I also edited the original post on behalf of the user for future clicks. :)
 
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