i have a 2004 z06. i am interested in changing the stock air box to something different . there are lots of sysems out there but which ones in your experience really adds horsepower. thanks for your thoughts. i have already swapped the stock air filter for a k/n. the box is stock.

 

Callaway Honker, Vararam and Blackwing are the most chosen ones

 

Actually, a 2004 Z06 already has a pretty good air induction system. I put a 2002 Z06 air top on my 1998 C5 Coupe. I don't want to chance with hydrolock.

 

 

Keep in mind that because your Z06 MAF has no laminar flow screen, swapping in a cold air intake may result in lean codes. If so, you will need to either replace your MAF with a screened version or get your car dyno-tuned. In any case, check with the manufacturer before you buy to see if any "issues" are to be expected. Here are a bunch of options:

If you live in California, think twice about the Vararam, as it can be a royal pain to install/uninstall/reinstall for smog tests. If you live in a state that doesn't have visual inspections, then take a look at the following (grouped by cold air and non-cold air, but in no particular order) and my comments, if any:

Vararam: Brings cold air in through the fog light panel area to a panel-type filter. Owners have had good luck with system on the dragstrip, but plan on spending hours to install and a bit more to get everything lined up well. Downside: Eliminates engine bay-cooling air that would've come in from the fog light panels (Z06 or coupe/vert with opened-up panels), so the engine bay may end up being toastier, especially if you add headers later. $300-$400 (NOT smog legal in CA)

Vortech Rammer: Brings cold air up from in front of the radiator and into an enclosed box. Its filter is quite a bit smaller than the Halltech Warhead or Blackwing unit. $250 (NOT smog legal in CA)

Callaway Honker intake system: This one relocates the MAF so that it is just in front of the throttlebody. It directs cold air from underneath and costs about $500. I believe this unit is 50 states legal (smogwise) for non=Z06 C5s. Excellent design and quality. If cost is no object, this bad boy should be at the top of your list.

K&N FIPK: This is more of a semi-cold air system, as the cold air intake opening is more of a slit. Its filter endcaps are carbon fiber. However, it is configured similarly to the Halltech Stinger-R and is 50-states legal. $350

Reverse Zip-tie: Allows cold air to be drawn in from underneath, but the bare filter is exposed to potential damage from larger objects. The advantage here is that you may pass smog if the tech doesn't know "which way is up".

Warm air systems: (Easy installation)

Halltech Stinger-R: Not only contains the massive Warhead filter, but also includes a larger-than-stock airbridge and smooth throttlebody coupler. For $350.00 or less, this system represents one of the best bangs for the buck. Fortunately, if you don't like Z06 screens in front of cored-out fog light panels, (for about $40) you can add cold air induction. See my procedure at http://www.conceptualpolymer.com/corvette_c5_corner.htm
This is what I did and a swap to smog-legal status is very easy to do, as I have kept my Z06 intake box.

Halltech Stinger SSM: This intake system features an even larger filter than that of the Stinger-R, TRAP, and Blackwing. < $400

Blackwing: Includes just a large filter, but an excellent one at that. Its cost is close to that of the Stinger. Like the Stinger, it is not smog-legal in CA, but can easily be swapped.

Volant Twin Cone: This system gives you more open filter surface area than any stock box does and is well suited to an engine bay that gets cold air in from the fog light panels, as the filters are more or less in the air flow path. $265

2002+ Z06 airbox cover: A larger opening allows more air to be drawn in through the filter. Expect up to a 5 RWHP gain from this simple swap. $50

Zip-tie: An easy and inexpensive mod (eliminates the OEM box’s upper lid), but its sealing ability is questionable at best.

How good are they? My experience has shown that most will bump up RWHP by at least 10. The advantage of having cold air is that power will not be "dialed down" under slow moving/stop&go conditions.
You could easily lose 10 HP with a warm air system after engine bay temps rise during slow-moving conditions. Cold air prevents this from happening.

 

I love my vararam, It's not a daily driver. I have driven through severe rain storms without a problem though

 

Honker here.... nice gain and looks like it's supposed to be there

 

The Vararam probably provides for the best HP gain, but the Callaway Honker, Blackwing and Halltech Stinger are good filters too.