K&N Air Filters now available

I run K&N filters in everything I own to include the aircraft we manufacture, but I wouldn't put one in a Prius. The reason is a K&N does in fact has less resistance to airflow, there is less pressure drop across the K&N than there is in a paper filter. But a K&N does let through more fine dust than a paper filter does. Normally this is not a problem, but in the Prius there is another filter like object. It's activated carbon in a fine mesh bag immediately downstream from the airfilter. It's apparent purpose is to trap any fuel vapors that there may be in the intake manifold and hold them until the engine is re-started.
I'm afraid that this additional device would get clogged over time from the fine dust the K&N would let through to say nothing of the K&N's airfilter oil effects on it. The red sticky oil that K&N uses is the "magic" that makes it work and there is always a little extra oil on the filter. This oil has caused problems in other cars mass airflow sensors, but it is usually easily cleaned off. Not sure of it's effect on the vapor trap would be, so I'll stick with a paper filter in the Prius.

 

Very informative, thanks for the info. I used to run K&N in everything also, but I have converted to twin-air in my atv's. I also have an AFE full intake in my diesel, which makes a ton of difference.

 

I come from the opposite camp. I had one in the car I just clunkered for five years. I had a turbo seize and wasn't happy with what I found. The front of the inlet impeller was covered in oily grime.
It had 247K miles on it so it was due to be replaced.

The K&N was tossed the day the new turbo was installed and I ran OEM filters from that day on.

I pulled the turbo hose on the car the day before I turned it in for the C4C with 370K miles on it. The replacement Turbo impeller was spotless with 123K miles. I mean it looked like it was brand new.

I will never have a K&N in any car I ever own again.

There is also an air filter test over on Bobistheoilguy.com and the K&N was one of the absolute worst performing filters when it came to filtering.

So unless your planning on running the engine of your Prius over 4000 rpms on a regular basis there is absolutely zero benefits of running a K&N in it.

Just remember with K&N filters there are two camps, those who love them and those who hate them. You have make the decision which side makes the argument you agree with most.

 

Maybe not. I don't see anyone recommending the K&N

 

I too run K&N air filters across our fleet of four cars and a Cessna 172. I tested the Prius air filter by trying to breath through it and to my surprise was unrestrictive. Because it was breathing easy, I decided not to do the K&N on the Prius. I did not know about the inner filter so this time I'm leaving well enough alone and trusting Toyota with their filter. I tend to do the same with oil filters although I have a K&N oil filter on the Corvette and really like it.

 

Among the spin on type oil filters, the K&N and Mobil 1 are considered among the best, with Fram being among the worst. Sometimes you get what you pay for.

 

I've also heard good things about the K&N oil filters.