I got a lightly used k&n for free. Otherwise I wouldn't dish out the money to buy it. I'd probably just go to autozone and buy a few Spectra pieces, a barbed fitting from the hardware, and a decent oiled filter and put it together myself. And a piece of sheet metal to make a "box". If I was really feeling cheap, PVC works pretty well too.
Honestly, they are more upkeep and have potential to allow more dust past. A paper filter restricts some because it has to to filter out smaller particals. I'm not sure if they still do, but fram used to make a washable dry filter that claimed to flow better and still filter like a paper one. Maybe they made/make one for our cars?
PVC is a bad idea. It's been discussed at length before, but heating PVC to under hood temperatures releases some really nasty gasses.
The paper filters do catch more particles, but there has been extensive testing with K&N and similar brands and I've never seen any engine failures attributed to their use.
K+N is a respectable company , but cold air intakes for the street are a total
waste of money. Marketing at it's worst " for the consumer ".
I think you're spreading bad information in this thread. Even if you disregarded any power gains it still isn't a waste of money. If you're keeping the car for a while then the mileage difference plus not having to replace air filters will eventually add up.
I don't accept the premise that for street use they are a waste, but lets apply that premise to other modifications that people like us do. Are you trying to say that any performance modifications for street cars are a waste, or are they only a waste if they increase your top end? Either way, I think you are missing the point.
People like us that are into performance modifications for daily drivers want a fun car to drive. Do you have a problem with that?
In any case, I think you're dead wrong that gains in the top end aren't useful for a street car. It depends on where you drive. If you have to pass or merge at certain speeds it's incredibly useful. If I'm trying to pass on the way to work I'll go all the way through the top of second gear to do so. There are a couple of highway entrance ramps around here where merging is insane, and you have to go from a near stop to 65mph traffic before someone hits you. Those moments may not come every day, but some extra pep sure as hell has some value when you're in those spots.
I will say that I think a CAI or exhaust is a nice start and a fun mod, but you get a whole lot more out of them if you'll be doing more to the engine down the road. Creating better flow only helps so much on an otherwise stock engine.