Buddy,

I have BMC and liked them. added HP and dyno proven. I have seen a post regarding the K&N making the car lose power.

PN

 

Here's the post where someone tested the K&N:

http://www.funcarsonline.com/ubbthre...true#Post57988

The difference was neglible so I didn't pull my K&N out.

 

I posted a before and after result on a dyno on rennlist. Do a search under my handle it should appear

 

Be REALLY careful about casually changing the air filter on your car.

Keep in mind that the only way the filter is going to "flow more" is to filter LESS. After the air passes through your filter, it goes straight into your turbos...the long-term effect of particulates larger than the manufacturer decided was appropriate bombarding the turbos is very likely to damage the turbos over time.

K&N is a fantastic business...selling something nobody needs and few people get a benefit from yet nearly everyone thinks will help them.

Also that oil the K&Ns use is notorious for screwing up the MAFs on cars.

I'd leave it stock unless you don't care or you have access to a dyno to test it out.