My $5 CAI

[Black Pheonix]

I figured out a way to make a cai extremely cheap. What I did was got a 1.5ft section of 2in pvc, a 2" 90, and a 2" 45. I connected my old 2" flex pipe from the stock intake and routed it inbetween the motor mount and the coolant hose. Then i connected it to a 2" 90 and piped the 1.5Ft section (It might be less than that, you will have to measure and cut) straight down, kind of next to the fan, in between the hoses/wires whatever they are. At the bottom i placed a 45" and my air fliter, pointing towards the driver's side wheel. My KN already had a 45 bend in the rubber, but you need to total 90deg of bend. I glued the pvc pipe fittings to the pipe using pvc cement and clamped the rest using the clamps that came w/ the car.

I am now in the process of making a scoop out of sheetmetal or something. I live on gravel and it will probaly be sucking a lot more dirt from the wheels when i stop. Hopefully the scoop will prevent the filter from collecting dust from behind. Hope you find this helpful.

P.S. The turbo echo's of the pavement now. Its as loud on both sides as it used to be on the driver's side.

[no1kicker]

how much power is there to be gained by a cold air rather than a cone filter on the turbo?  Doesn't the turbo heat the air up anyway, and the IC cools it back down.

[The Burning Rom]

Pictures would be good! :)

[no1kicker]

yes I would also like to see some.  :D

[Black Pheonix]

I'll get the camera out this weekend and take some pics.

I reallly not sure how it works out, but i would have to say that colder air is denser air, and if denser air is compressed you would have more air air compressed by the turbo.

Either way i think that you would have denser air flowing into the throttle body. But a CAI helps N.A. cars more than turbo cars because you are heating up after the turbo again like no1kicker said. And perhaps the pressure drop negates the gain.

I'm sure Chris A or some other expert can explain it to us correctly

[GPChief]

I had done something similar, what I foud with the PVC pipe is that 2" is too small 2.5 or 3 with an reducer.  I am back to directly on the Turbo now.

[Black Pheonix]

was it slower or running richer or something? i can see that 3" would be better but my filter is 2" so i'm stuck w/ that size for now.

[GPChief]

my "butt dyno" noticed a huge differance, seemed to be sucking for more air.

[fatguy]

I have done some long hard looking at the whole CAI vs. directly on the turbo thing, and here is my opinion (highly educated):
The CAI brings in air, cooler of course, from the bottom of the engine compartment.  Unfortunately, this is a low pressure area due to the airdam (unless the intake is in front such as the stock is).  Thus there is no ram air effect, just cooler air.  
Problems with CAI:  lots of piping and bends.   According to my Fluid Dynamics book, a bend has the same resistance of a straight section of pipe 5 times it's length.  Air also has trouble negotiating around them, and at high velocities such as full boost, can cause turbulance.  This actually makes a restriction for the air.  Since you are not runing high speeds 100+mph there is problems with the air pickup.  
The turbo still takes the air and compresses it, generating heat.  Since the temperature gradient is greater with CAI, there is a greater chance of heat soak due to heat transfer driven by temp. differentces.  This then completely negates the effects of the CAI and throw in the "resistance" of the setup potentially means less air at the same temps.  The intercooler then has less mass flow through it causing less heat transfer across the IC.  
The bends can cause serious problems.  Why do they make mandral bent pipe? Of course this can be eliminated by going with way oversize pipe!
Problems with filter directly on turbo.  Taking in warmer engine bay air.  There is more potential for more air due to no piping.  The intercooler is actually more efficient due to larger quantities of air.  
Positives about CAI:
HIGH SPEED DRIVING CAN CREATE A RAM AIR EFFECT
Positives about directly on the turbo:
Clean looks
more efficient
There are lots of other mods that create more power.  Some free (not including time) some not.
The best ways to get these cars faster is:
1)put them on diets
2)make the intercooler more effiecient
 The best way is to remove the AC condensor fins and put a switch on the secondary fan and keep it running whenever you want to race.  The fin removal provides tons of extra mass flow through the IC, and then directly into the turbo creating a ram air of sorts.
Spray some sort of low boiling point liquid onto the IC to aid in heat transfer.  
3)dry nitrus kit.  This additionally cools the post compressed air.  
I've talked with my professor and he thinks it would be a great IC engines lab project to see if my hypothosis is correct?  

I've thought and looked long and hard this summer and this is what I came up with.  If you wish to refute it, please do, maybe you will bring up points I haven't thought about and other things to test for :lol:

[Black Pheonix]

I would have to agree w/ you. Of course my tgp didn't really feel slower to me, and pvc is essentianly mandrel bent, just tight bends, but i do definately agree it probaly has a hard time sucking and air, and the best thing to do is increase the efficentcy of the ic.

[mclaren18psi]

I have kind of solved the bends problem. I started thinking that if i repiped over to stock inlet and then coned the end of the pipe in the bumped it would be better.  Wrong after running like this a while and felling satisfied, I pened the hood and the pipe was heat soaked from the manifold.  I knew this wasnt good so i ripped it all out and went to the filter on the turbo...  still not happy i started planning im almost done now i have had ne ic pipe bent and i have a freind thats workign in a ac shop work with me :P free labor rules. Anyways we took the condencer and pinched the pipe in three places and cut it out and then rolled and re crimped the lines.  Theholes in the ac didnt afect the oporation just pinch befor cutting not to loose freon. The three holes not will have my inlet and outlet for the ic, and a  third pipe that runs the filter into the front bumper ill post pics as soon as were done. For all that care i and running the stock ic with the bottem pipe running be hind, i also have a cryogen set up in the works....

[TGPRobNY]

I use a KN directly on the turbo, no bends since it does slo down air and more importantly I double wrapped the IC to throttle body pipe several times with heat tape to keep it cool and isolated from the engine bay heat.  It has great kick and the cooler weather is starting here in NY and man it's fun!   Good luck!