Replacing air filter

[thstone]

I've used a K&N filter and a paper filter. I've never noticed any difference in power or engine sound (at least that I can readily detect). I have kind of settled back to using stock paper filters just because cleaning the K&N takes more time than throwing the old paper filter in the trash and taking the new one out of the box.

[McQuaid]

With stock paper filter,ni did hit a desirable engine noise until at least 4k revs, before that it was almost and electric sound as it revved, but now, right from the off I'm getting a lovely rumble throughout the range

[shlim8]

When I added a bmc drop in filter, together with the ipd plenum, the intake became alot louder although mine's not desnokled.

I guess the freer flowing bmc filter, with the elimination of the air resonance box on the stock pipe, the larger tb and presumably the smoother flow of air through the plenum, all contributed to create more noise.... and it's a nice noise... Car used to be too "civilized". Now, if I can improve on the exhaust... without causing a headache on my regular 3 hr highway commutes.

In my case, the noise increases significantly after 4k rpm... loud enough to startle my sleeping passenger....