K @ N Filter
#16
Super Moderator
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#17
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In the classic car and muscle car world, there was a thread on this where mileage was discussed and K & N filters came up. To give the reader's digest version - "there ain't no free lunch". One of the ways to improve mileage is to improve breathing which means a freer flowing air filter. The gist of the discussion was that K & N gives a freer flowing air filter by allowing more particulate matter through their filtering medium. So, you MAY get a mile or two better fuel economy but probably at the expense of increased internal engine wear.
Just my opinion.
Gary
Just my opinion.
Gary
#18
Lexus Champion
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you realize that you can always remove the stock air box then put a round type filter on the end and leave everything else including the stock hose and connectors the same. my mechanic said that just repalceing the filter should not be a reason for a dealer to refuse to work on your car.
#19
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Gary is right. The net free area determines volume of air. K N allows more air, less media...is it allowing particulates to go through....maybe debatable...but concept is right.
#20
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the oil from the filter contaminating the MAF sensor. This has been reported as a problem on a BMW forum I frequent. Plus as I have pointed out before unless you install some sort of better exhaust system you can not flow more air effectively if it has no where to go. So, how about a cold air intake AND a set of headers and dual exhaust the whole way back. Unfortunately, I have never seen a performance exhaust or cold air intake for the RX. Anyone else?
#21
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Todd has a valid point...CAI alone will not add HP, you will maybe like the sound....but Lexus is trying to absorb the noise.....
#22
Lexus Test Driver
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There have been a few independent studies on aftermarket filters and found them all to filter less effectively. In addition, they tend to clog up faster than paper filter.
#23
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Also the re-charge kit is expensive....I have always stuck with paper filters...
#24
Lexus Test Driver
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I use to use K&N filters, but recently switch to TRD filters. I just replace them every 2 years. They cost twice as much as the OEM paper filter, so its a wash price wise.
#25
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Where do you purchase the TRD filters?
#29
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The oil compensates for the lesser media....in effect, filtering the same but allowing more flow....
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