I had lost this link to the study of air filters, some surprising results here:

http://moto.lexp.net/wiki/ISO_5011_D...er_Test_Report

 

Yeah. The K&N didn't do too well.

 

[QUOTE=CEB;5740597]Nice write up but let's be realistic here - a 15% increase in gas mileage is impossible.

Thanks for a fine post. Air filter technology is well known to all the major filter producers. The most common limiting constraints to better filtration are potential air flow restriction, money, and installation space. The K&N filters represent one technology that can be used (oiled filtration media) but not one that many original equipment manufacturers have chosen, including those that make very expensive commercial engines. Mercedes has chosen a very excellent oil filter media and I have some doubt that they would have deliberately used an air filter that is easily surpassed by the aftermarket.

 

Nice. Does the 2014 E550 4Matic have the identical filter change procedure?

 

Aftermarket air filters are BS.


So are cold air intakes and it doesn't get any less restrictive than this:

 

Wondering if anyone noticed the inside if the box where the filters sit are a little restricted ? Looks like some grooves that can maybe taken out with a dremel too or something

 

Car makers usually take a systems approach to car development and try to optimize the thousands of parts that are involved. I doubt that any easy major gains have been carelessly overlooked by Mercedes-Benz engineers.

 

So are cold air intakes and it doesn't get any less restrictive than this:

[/QUOTE]

I knew about the filters being of little to no value but was surprised by the cold air intake results. Thanks for the post Greg.

 

Just the size difference in the k and n vs the stock filter element is enough to tell me there is a difference. K&N is smaller and thinner. . However very minimal gains , if any