K & N Air Filter

i asked that question a few months ago

http://priuschat.com/forums/prius-modifications/49301-k-n-airfilter-anyone-done.html

 

np i definitely dropped my plans to spend 40 bucks on one. if you have one i guess it wouldnt be a bad idea to hold on to it and use it when you need a replacement filter. 40 more bucks for me to put towards my scangauge!!!!

 

I won't be trying the K&N on the Prius for awhile for warranty reasons, but used them on my Accord and 240 throughout their "after lives" (after the powertrain warranties expired.) In both cases I used "funnel ram"/air horn set ups rather than drop in filters. The 240 was a tiger with the K&N Stillen Pop charger, did back-to-back testing and improved 0-60 by 0.5 sec--nice throaty sound, even my wife was impressed at how it changed the character of the car. The Accord got a boost as well from an Akimoto Funnel Ram K&N, just not as much (wasn't as limited on the intake side as the 240), but my wife was enthusiastic as she could pass better with it and other drivers looked over wide-eyed when the VTEC cam kicked in and the whoosh started.

Neither one had any problems and I raced the 240 often, it saw redline every single drive for 100,000 miles after warranty expired. I'm not sure what the K&N will do for the Prius ICE. It might give it a little more passing/merging power but I wouldn't expect much. I doubt you will see any mileage improvement for example. The only way to find out is to try it. Nothing beats empirical evidence.

Having put hundreds of thousands of miles on K&N's in dusty conditions in the past I'm not exactly concerned about fears it will wear out my engine. In the decades I've been driving I've found one constant: other drivers are hell bent on destroying your vehicle somewhere before 200,000 miles, so don't worry about preserving the engine past 150K.

 

I have used K&N filters for many years. All you will notice is improved horsepower at freeway speeds as the engine will be able to breath better. No improved fuel savings but since this filter can be cleaned you will save money by not having to buy new engine filters (although you do have to buy the K&N filter oil). One word of caution, do not over oil the filter after a cleaning or you will void your engine warranty, as excess oil can clog an engine MAF sensor.