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Thread: K&N Air Filters
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Old 01-29-2013, 09:19 AM
ard ard is online now
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Location: Sierra foothills, California USA
Join Date: Jul 2009
Posts: 15,892
Mein Auto: '12 X5 35d/E39M5/996TTX50
Originally Posted by Griffin 27 View Post
Wow those are some interesting graphs and results, thanks for posting !!!
This has been around for quite a few years. Actually, it was so damaging to the aftermarket filter vendors that they felt the need to 'counter' this in their marketing- hence you began to see "ISO 5011 Testing" data on their websites over the last few years- of course, the critical fact is that they only present very select pieces of data.

When you look at an ISO 5011 done by a test house, typically they require that the entire report be published. Whereas filter vendors just run their in house tests, maybe don't specify media size, and publish whatever they need to deflect criticism.

People like to think there is some 'magic' solution to 'flow/vs/filtration. there really isn't. Yes, you can deflect the curve one way or the other, just a bit, but not appreciably, and not for 10k, 20k, 50k miles. (ie 'lifetime'). And remember, race cars are rebuilt every year- don't buy a filter because they use them on race cars....
Keep it as simple as possible...but no simpler.
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