Sorry to ressurect this, but I had to interject.
CAI intakes will always provide more torque and better timing advance then a standard WAI.
Also if you throw a heat shield around a WAI, you are creating more restriction at high RPM, and if you say no Im not creating more restriction, then your still drawing in warm air. Its that simple. If your filtering the air that is available to the engine (heatshield) then your a forcing a new path for air to be selected from, hence creating more restriction. (Even if its slight)
I used to manufacture custom CAI's for Hyundai between 2000-2004, I sold about 100-150 on ebay. I got bored of it, and the money in it dried up as my designs got copied
... and I was jsut doing this on the side anyways. But... I will come up with something, one piece, mandrel bent for the CSVT shortly. I just got my first one yesterday
The fenderwell CAI is the best you can get as far as performance is concenered, hands down. Drawing from on top of the hood or through a hood scoop yields trouble in city traffic (warm air rises) but offers benefits (RAM air) on the highway. This had been dealt with on many forums and many cars, and unless the CSVT has a very well vented engine bay.... it will apply.
The absolute best NA (temperature) setup (aside from porting/TB's etc) would be a heat wrapped true fenderwell CAI with a wrapped header and a custom exhaust with a hood vent blowing onto the Intake manifold.
I dont have my notes here, but as most of the Hyundais I dealt with were 2.0L's I had an example of an empty 2L of pop in 75 degrees and in 105 degrees.
With the cap on in 75 degrees, placing the bottle into 105 degree weather yields a hair over 1.4 PSI (or around 10% increase) of pressure. Boost is power.
Also taking the 105 degree bottle with the cap off and placing it into 75 degree weather (or water) caused the bottle to decrease in volume by about 10%.
The bottom line is there is more air molecules in 2.0L of cold air, then 2.0L's of warm air.
You can verify any numbers you'd like using the gas pressure vs temperature equations available at:
http://en.wikipedia.org/wiki/Density_of_air
It is HIGHLY... unlikely that a WAI with a shield will be within 1-3 degeres fahrenhight of a true CAI. I measured an average of 25 degrees F difference after 10 minutes of runtime, and that was on a nice big enginebay with a small engine.
http://www.members.shaw.ca/diatech/Tiburon/Engine.jpg
I measured up to 50 degrees difference while sitting in traffic. This really.. really... retards the timing, and it wont clear right away as soon as you get cold air again.
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Bottomline:
There are 3 disadvantes to a true CAI:
1) Hard to install
2) HARDER to keep clean (danger of engine damage in deep water)
3) There can a "slight" (I mean like 200 ms) increase in throttle response time, due to the longer pipe.
The 4 big advantages:
1) More TQ throughout the powerband
2) Means higher average HP
3) A slightly greater peak HP
4) Less chance of detonation.
The big one is the TQ, you will pick up more peak TQ with a true CAI, noticably moer, but your peak HP may only increase slightly (2-3 HP) due to other restrictions at high RPMS.
Hope this helps clear up the debate... or at least add to it
-Steve