There are several concerns to take into account. First is the temperature of the incoming air. Colder is better because it'* denser. That means more air. Second is laminar flow. Turbulent air doesn't flow as well. If you look at the way the air enters a cone and transitions to the plenum, you can see that there is a laminar advantage when compared to a square or rectangular filter transitioning to a round plenum. In addition, laminar airflow is more accurately measured by the MAF sensor.

All in all, a good full intake can be 'felt' by the seat-of-the-pants dyno. The various setups from worst to best:

1. Stock airbox, paper filter.
2. Stock airbox, performance filter.
3. Stock GUTTED airbox, performance filter.
4. Custom intake with cone filter, unshielded.
5. Custom intake with cone filter, shielded from heat (CAI)
6. FWI

The last 3 or 4 might be out of order by some opinions, but not by more than one place on the list. In my opinion, the best intake setup for a 2000+ SSEi is 2000SilverBullet'*. Straight shot, insulated from engine bay heat, good filter.

Obviously, a good intake will benefit the supercharged cars more than the NA, but all benefit from it. Snappier throttle response is a nice side-effect as well. Can you feel it? You bet, especially if you have supporting mods like a pulley and/or exhaust.

I do think NA might do great, because NA is all about removing restrictions, as SC is about brute puling of the air But SC may gain a little more. Only way to know is to Dyno the stuff like mad.

IMO a Fenderwell and a Sheilded, and ducting fed filter behind the headlight is the same as a FWI, it just has the filter in the middle of the system, instead of the end. Differences are probably VERY close.

As stated previously many times, a motor is just a big bump. The better it breaths, the better it pumps, the more power it makes. On a stock engine a better flowing intake will probably only raise power by a few HP. However on a modded engine the incoming air can be a limitation. Freeing this up by allowing more air to come in benifits the overall "pump".

IMO FWI is the best option not only for 2K+ but for all setups. Air is sucked in from an isolated bay (no swirling like a ram air and no heated air from the engine bay) It'* also longer then 2KSB'* straight shot allowing time for the air to smooth out before reaching the MAF sensor. A larger filter and better filter (better paper, cloth whatever) allow more CFM and hence better breathability.

Will a FWI be better than a gutted airbox on a stock engine? Maybe slightly but not by much. Will it perform better on a modded engine, absolutely.

As an example my car produced up to 7 degrees of KR with an SLP CAI, When I went to FWI it disappeared totally. I'm sure many ppl have examples of how better flowing boxes or FWI outperformed stock boxes or gutted boxes so I'll let them post here but I will just say that you'll not see fast bonnevilles with stock intakes (or gutted boxes for that matter)

The cone setup flows just about the same direction as the stock setup. Dont matter what the filter is shaped like, as long as its smooth in the tube going into the engine.

Longer and accordianed = more turbulence = more resistance = more pressure drop.

My 4" straight shot is completely smooth inside, unlike the FWI very long accordian tube that makes a few turns and which has to produce more resistance and turbulence.
If only they could develop a tube with smooth inside walls.

The key is the colder charge the FWI gets by taking the air from inside the fenderwall.

Also using a cone with pleats in the end helps to smooth out the air flow as it passes thru the filter.

It made a huge difference for me once I isolated the engine bay heat (130*F) and now ram outside temp air into the intake.

I do agree that the FWI for 2000+ Bonne'* is better than an SLP box that still uses the factory accordian tube and draws all of the air thru the factory 3 1/2" fender wall opening but my shielded ram cooled straight shot is a better option IMO.

silly question, will one of those intakes at atuo zone work for my car until i can find a K&N?

Actually the INTENSE tubing is complete smooth inside.

Of course the intake will work, but I would say stick with it, dont go back to stock, even if its just a drop in K&N.