I belong to a GM Truck Site (My other Vehicle is a GMC Sierra) and thought this was interesting:

http://home.usadatanet.net/~jbplock/ISO5011/SPICER.htm

Lou

 

So Are They Saying K And N Is Bad, Or Is Amsoil Bad?

 

It shows that K&N is almost the worst!
hmmmmmm.

Thanks for posting Lou.
C.

 

I switched over to the Amsoli filter for the better filtering properties and maintenance, which the Amsoil affords.

 

Correct me if I am wrong here, but doesn't GM parts use AC Delco parts? In that site AC Delco comes out on top.

Amsoil is no good then?


Gosh darnit, now what do I choose next? I am lost! I need an engine air filter soon because it's time to change!

 

Air filter panels create so little resistance [pressure drop] from atmospheric pressure that it is almost unmeasurable, even with very sensitive manometers.

1" water column = 1/28 or 0.0357142 psi........x 6.8 ~~= 0.24%

Nissan has for the past 16 years used at max 0.25% restriction at redline as the engineering criteria. The size of such panels must be measured by ironing out the convolutions.

90% of driving is below 4,000 rpm so REAL filtration not marketing hype is what counts.

 

If you search google for K&N tests or air filter tests, you will find test data the both supports K&N style filters and others that don't. There's alot of data out there. Hard to know which to believe.

 

It's not "hard to know which to believe" at all.

Follow the money.

You have, in the article above, independent and thorough testing which clearly shows the difference (the same difference all of us who swear by OEM filters have known all along).

Hell, I knew this back in the 80's when I ran a K&N on my old GranSport and wondered why the carbs were always full of black funk.

Amazing that someone would spend $50 for a K&N for 3 rwhp and then bolt on 15 lbs of rotating mass per aftermarket wheel and lose 20 rwhp.

It's "ricer math" in action, folks.

 

But many of the tests I found online were NOT published or performed by the filter maker