i don't think my k&n did much of anything.. :dunno: however, i can supposedly leave it in for 100k without it requiring a cleaning. i'm too paranoid to go that far; although, supposedly the dirtier it gets, the better it filters.

but again, i didn't notice a change in anything. i may as well go back to a paper filter, but the k&n does look cool.

edit > i lied. i did notice one thing. depending on the weather, at certain throttle positions, i can hear a faint whistle. i never heard this on the paper filter. that's all. i'm a ricer. h: