I was wondering if i should instal a KnN filter, but how does this effect the 01 F4i?
I have heard that it actualy slightly decreases horse power? or does it increase....

 

With a full system, you might need the extra air coming in, but with that comes more dirt. Their selling point is that they are reuseable, which to me is a negative. It takes less time to buy a new OEM filter every two years and drop it in and go, than to have to buy cleaning kits, remove the K&N, clean it, dry it, re-oil it and put it back in. It's a waste of my time and it does not really save me much money... Maybe $20 a year?

If I factor in my time, I am losing money with the K&N, and so I stick or OEM. Honda spent a lot more money on R&D for the airbox and filter than K&N did.

 

he's right, the 1 HP increase is not worth the hasle,

 

K&N is a good product line but the key is to make sure after you clean the filter you re-apply oil to the filter. Most people dont realize that the filter has oil on it to start but after you clean it, you just removed 90% or more of the oil. Have to spray more oil back on it to trap the dirt. Amsoil has an awesome line of these type of products too. I should know because i'm an independent dealer for AMS. Now don't think that i am biased, I became a dealer to get AMS products at wholesale prices. I use AMS products in all my motors. I save on fuel costs and oil change costs due to only having to change oil and filters once a year. I suggest you check AMS products out for more info.