I swiss cheesed my airbox this evening. Watercooled VW enthusiasts have been doing this since the 80's. I used to have swiss cheese airbox in my GTI before my TC.

How to:
-remove stock airbox
-drill holes in bottom portion of box (do not drill the top of the box) facing away from the engine.
-for best results use a K&N-type panel filter, and remove the stock charcoal filter.

After I installed everything, I noticed a louder-deeper intake sound (duh).

Performance is debatable. Some people say it takes away HP because it sucks in hot engine air, but a short ram intake without a heatshield would be worse. Some people say this is better for low-mid range power, whereas a CAI is better for high end. All I can say is its a cheap mod.

An observation about CAI's:
No major Japanese aftermarket parts manufacturer makes CAI's. HKS, Apexi, Trust/Greddy, Blitz and others make "short ram" intakes for a variety of cars, but not one CAI. If you look through Japanese tuning magazines (Option, Option 2, Drift Tengoku, Carboy, etc), the feature cars dont run CAI's. European manufacturers dont make CAI's either. To my knowledge K&N, Injen, and AEM (all US companies) are the only mass producers of CAI's in the world.

I can totally see and agree with the logic behind a CAI, but I wonder why it hasnt caught on world wide.

 

I like the idea, but it seems that fewer holes that were much larger would be more effective.

 

Hmm.... Very interesting
I hope you gained something out of it, but I don't think were all going to hop on this wagon.

 

LOL. yeah. thats as large a hole my dremel could make. some VW guys just cut a big chunk off the box rather than drill holes.

 

Well I see my Air box made it there. Hope it was what you needed.

 

poor man's intake, i love it

 

On the contrary, HKS (USA) makes CAI's for BMW. GruppeM (UK) and Carbonio (CAN) also make CAI's for BMW. I used to own one so I did shopping around.
Also, Jim Conforti (USA) and Dinan (USA) make CAI's for BMW and have been at the top of the BMW tuner market for the better part of 25 years.

And you just horribly and utterly destroyed your factory intake box.

 

 

HKS killed their Klasse euro line of parts years ago. that line did not include a CAI. HKS is also a japanese company, not "USA". Their Los Angeles office is a subsidiary. www.hks-power.co.jp

GruppeM is a Japanese company, not UK (they have an office there, just like their US office in Los Angeles). www.gruppem.co.jp. GruppeM's intakes are molded carbon fiber airbox replacements that keeps the intake in the stock location not at the end of a enlongated intake tube.

Carbonio does make CAI's, but theyre a BMW and VAG specialist. Eurosport in California makes CAI's, but just for VW. Theyre still a north american company that caters to a specific vehicle brand. I was referring to larger companies who manufacture for a variety of cars, but thats my fault for not specifying. ITG in England rivals K&N in performance filter applications, but they dont make CAI's.

edit: HKS does make a CAI for the EK. my bad.

 

 

Looks interesting, to say the least

 

Might I point out that the length of the tube effects where
the added power is. A longer tube is supposed to help in
the lower RPM range and a shorter tube the higher RPM range.
Which is why people say Short Air effects their top end power the most.

Same thing for headers.

A properly designed, tested, and tuned CAI can and should
be dialed in to hit a specific RPM range.

Hey, did you guys ever see the Simpsons episode where
Homer puts "speed holes" in his car?

 

Very interesting points you have there.

BTW, I saw a used stock airbox on Ebay for 10 shipped the other day. Good to know you can get a replacment for cheap if you need engine warrenty work done.

 

that so fits this mod

 

I couldn't resist.